Finbase API Documentation

Use Finbase APIs to access maintained income-limit data, geography mapping, derived income limits, and rent limit calculations through documented HTTPS endpoints.

API Base URL https://api.finbaseco.com/api/service/v1

Authentication Authorization: Bearer <api-key>

Current Examples HUD / Section8 / FY2026

Getting Started

All organizations begin with a free evaluation trial. After creating a Finbase account, users with API key permissions can create API keys from the account portal and use those keys against the Finbase API.

Create or sign in to a Finbase account.
Open the account portal and create an API key.
Store the API key securely in your application or secret manager.
Send authenticated requests to the production base URL over HTTPS.

API keys are issued to the subscribing organization or individual and should not be shared outside the permitted subscription relationship.

Authentication

Finbase API requests use bearer-token authentication. Include the API key in the `Authorization` header for every request.

Example Request

curl "https://api.finbaseco.com/api/service/v1/data/fixed/il/sets?datasource=HUD&datasettype=Section8&fiscalyear=2026" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Accept: application/json"

Response Envelope

Successful Finbase API responses use a consistent envelope with input echoing, metadata, data, pagination, and rate-limit context.

Response Shape

{
  "status": "success",
  "input": { "...": "request values after normalization" },
  "metadata": {
    "resource": "fixed-il-sets",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": []
  },
  "data": [],
  "pagination": {
    "totalRecords": 0,
    "totalPages": 0,
    "currentPage": 1,
    "recordsPerPage": 200
  },
  "xRateLimit": {
    "period": "202606",
    "reset": "2026-07-01T00:00:00.000Z"
  }
}

Fiscal year and effective date filters: Use fiscalyear when you need the data set matching an exact fiscal year. Use effectivedate when you need the data set active for a specific date; Finbase resolves the request to the released data set whose effective-date range contains that date.

OpenAPI Specification

Download the Finbase Service API OpenAPI specification to import the API into tools such as Postman, Insomnia, Swagger UI, Stoplight, or internal developer portals.

Specification scope: This file documents the public Service API v1 surface, including authentication, request parameters, response envelopes, source metadata, data-set aliases, and representative response examples.

Download Service API OpenAPI Spec

Geography Reference

Geography reference endpoints provide generic state and county lookup data. These endpoints are not income-limit-specific.

States

Returns state reference rows with state code, abbreviation, and name.

GET /data/geo-map/states

Parameters

Parameter	Required	Sample Value	Description
`page`	No	`1`	Page number for paginated responses.
`limit`	No	`10`	Maximum records per page.
`statecode`	No	`36`	Filter by state FIPS code.
`stateabbr`	No	`NY`	Filter by two-letter state abbreviation.

Example Request And Response

GET https://api.finbaseco.com/api/service/v1/data/geo-map/states?limit=10

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

limit 10

Response Body

{
  "status": "success",
  "input": {
    "limit": 10,
    "page": 1
  },
  "metadata": {
    "resource": "geo-map-states",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "dataSize": 10
  },
  "data": [
    {
      "stateCode": "02",
      "stateAbbr": "AK",
      "stateName": "Alaska"
    },
    {
      "stateCode": "01",
      "stateAbbr": "AL",
      "stateName": "Alabama"
    },
    {
      "stateCode": "05",
      "stateAbbr": "AR",
      "stateName": "Arkansas"
    },
    {
      "stateCode": "60",
      "stateAbbr": "AS",
      "stateName": "American Samoa"
    },
    {
      "stateCode": "04",
      "stateAbbr": "AZ",
      "stateName": "Arizona"
    },
    {
      "stateCode": "06",
      "stateAbbr": "CA",
      "stateName": "California"
    },
    {
      "stateCode": "08",
      "stateAbbr": "CO",
      "stateName": "Colorado"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "stateName": "Connecticut"
    },
    {
      "stateCode": "11",
      "stateAbbr": "DC",
      "stateName": "District of Columbia"
    },
    {
      "stateCode": "10",
      "stateAbbr": "DE",
      "stateName": "Delaware"
    }
  ],
  "pagination": {
    "totalRecords": 56,
    "totalPages": 6,
    "currentPage": 1,
    "recordsPerPage": 10,
    "nextPage": 2,
    "prevPage": null
  },
  "xRateLimit": {
    "period": "202606",
    "limit": null,
    "remaining": null,
    "reset": "2026-07-01T00:00:00.000Z",
    "unlimited": true
  }
}

Counties

Returns county reference rows and can be filtered by state or county identifiers.

GET /data/geo-map/counties

Parameters

Parameter	Required	Sample Value	Description
`page`	No	`1`	Page number for paginated responses.
`limit`	No	`10`	Maximum records per page.
`statecode`	No	`36`	Filter by state FIPS code.
`stateabbr`	No	`NY`	Filter by two-letter state abbreviation.
`countycode`	No	`119`	Filter by county FIPS code.
`countyname`	No	`Westchester`	Filter by county name.

Example Request And Response

GET https://api.finbaseco.com/api/service/v1/data/geo-map/counties?stateabbr=NY&limit=10

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`stateabbr`	`NY`
`limit`	`10`

Response Body

{
  "status": "success",
  "input": {
    "stateabbr": "NY",
    "limit": 10,
    "page": 1
  },
  "metadata": {
    "resource": "geo-map-counties",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "dataSize": 10
  },
  "data": [
    {
      "stateCode": "36",
      "stateAbbr": "NY",
      "stateName": "New York",
      "countyCode": "001",
      "countyName": "Albany County",
      "countyNameAbbr": "Albany"
    },
    {
      "stateCode": "36",
      "stateAbbr": "NY",
      "stateName": "New York",
      "countyCode": "003",
      "countyName": "Allegany County",
      "countyNameAbbr": "Allegany"
    },
    {
      "stateCode": "36",
      "stateAbbr": "NY",
      "stateName": "New York",
      "countyCode": "005",
      "countyName": "Bronx County",
      "countyNameAbbr": "Bronx"
    },
    {
      "stateCode": "36",
      "stateAbbr": "NY",
      "stateName": "New York",
      "countyCode": "007",
      "countyName": "Broome County",
      "countyNameAbbr": "Broome"
    },
    {
      "stateCode": "36",
      "stateAbbr": "NY",
      "stateName": "New York",
      "countyCode": "009",
      "countyName": "Cattaraugus County",
      "countyNameAbbr": "Cattaraugus"
    },
    {
      "stateCode": "36",
      "stateAbbr": "NY",
      "stateName": "New York",
      "countyCode": "011",
      "countyName": "Cayuga County",
      "countyNameAbbr": "Cayuga"
    },
    {
      "stateCode": "36",
      "stateAbbr": "NY",
      "stateName": "New York",
      "countyCode": "013",
      "countyName": "Chautauqua County",
      "countyNameAbbr": "Chautauqua"
    },
    {
      "stateCode": "36",
      "stateAbbr": "NY",
      "stateName": "New York",
      "countyCode": "015",
      "countyName": "Chemung County",
      "countyNameAbbr": "Chemung"
    },
    {
      "stateCode": "36",
      "stateAbbr": "NY",
      "stateName": "New York",
      "countyCode": "017",
      "countyName": "Chenango County",
      "countyNameAbbr": "Chenango"
    },
    {
      "stateCode": "36",
      "stateAbbr": "NY",
      "stateName": "New York",
      "countyCode": "019",
      "countyName": "Clinton County",
      "countyNameAbbr": "Clinton"
    }
  ],
  "pagination": {
    "totalRecords": 62,
    "totalPages": 7,
    "currentPage": 1,
    "recordsPerPage": 10,
    "nextPage": 2,
    "prevPage": null
  },
  "xRateLimit": {
    "period": "202606",
    "limit": null,
    "remaining": null,
    "reset": "2026-07-01T00:00:00.000Z",
    "unlimited": true
  }
}

Income Limit Data Sets

Use the data-set listing endpoint to discover released income-limit data sets available to your subscription, including canonical data-set identifiers, supported aliases, entitlement category, and geography coverage.

Available Data Sets

Lists released income-limit data sets, including canonical source, data set type, fiscal year, effective date, release date, source program metadata, geography coverage, and supported aliases. Use these values to select the source and data-set parameters for income-limit lookups.

GET /data/fixed/il/sets

Parameters

Parameter	Required	Sample Value	Description
`page`	No	`1`	Page number for paginated responses.
`limit`	No	`5`	Maximum records per page.
`datasource`	No	`HUD`	Canonical data source or supported alias filter.
`datasettype`	No	`Section8`	Canonical data set type or supported alias filter.
`statecode`	No	`36`	Returns national data sets plus data sets covering the specified state FIPS code.
`stateabbr`	No	`NY`	Returns national data sets plus data sets covering the specified state abbreviation.
`fiscalyear`	No	`2026`	Matches the released data set fiscal year exactly.
`effectivedate`	No	`2026-05-01`	Finds the released data set whose effective-date range contains this date.

Aliases and defaults: Some data sets expose customer-friendly aliases that resolve to the canonical source and data set before lookup. When datasettype is omitted, Finbase can apply a documented default only when the source resolves unambiguously.

Example Request And Response

GET https://api.finbaseco.com/api/service/v1/data/fixed/il/sets?limit=5

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

limit 5

Response Body

{
  "status": "success",
  "input": {
    "limit": 5,
    "page": 1
  },
  "metadata": {
    "resource": "fixed-il-sets",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "dataSize": 5
  },
  "data": [
    {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-15T17:31:37.890Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD",
      "geographicScope": "NATIONAL",
      "states": [],
      "aliases": []
    },
    {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2025,
      "effectiveDate": "2025-04-01T00:00:00.000Z",
      "releasedDate": "2025-04-04T20:44:20.395Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD",
      "geographicScope": "NATIONAL",
      "states": [],
      "aliases": []
    },
    {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2024,
      "effectiveDate": "2024-04-01T00:00:00.000Z",
      "releasedDate": "2025-03-10T00:29:44.717Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD",
      "geographicScope": "NATIONAL",
      "states": [],
      "aliases": []
    },
    {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2023,
      "effectiveDate": "2023-06-15T00:00:00.000Z",
      "releasedDate": "2025-03-10T00:29:14.170Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD",
      "geographicScope": "NATIONAL",
      "states": [],
      "aliases": []
    },
    {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2022,
      "effectiveDate": "2022-04-18T00:00:00.000Z",
      "releasedDate": "2025-03-10T00:28:42.204Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD",
      "geographicScope": "NATIONAL",
      "states": [],
      "aliases": []
    }
  ],
  "pagination": {
    "totalRecords": 13,
    "totalPages": 3,
    "currentPage": 1,
    "recordsPerPage": 5,
    "nextPage": 2,
    "prevPage": null
  },
  "xRateLimit": {
    "key": "Example API Key",
    "period": "202606",
    "limit": null,
    "remaining": null,
    "reset": "2026-07-01T00:00:00.000Z",
    "unlimited": true
  }
}

Income Limit Area Mapping

Income Limit Area Mapping endpoints explain how a source data set maps counties or subcounty names to income-limit areas for a selected data source, data set type, fiscal year, or effective date.

Mapping distinction: County-to-Area Summary is a diagnostic/count summary. County Lookup Areas Only, listed under Fixed Income Limits, returns the by-county lookup shape without income-limit values.

County-to-Area Summary

Returns county rows with areaMapCount, useful for identifying whether a county maps to one or multiple income-limit areas.

GET /data/fixed/il/map/counties

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear`	No	`2026`	Matches the released data set fiscal year exactly.
`effectivedate`	No	`2026-05-01`	Finds the released data set whose effective-date range contains this date.
`statecode / stateabbr`	No	`09 / CT`	State filters.
`countycode / countyname`	No	`001 / Fairfield`	County filters.
`splitcountiesonly`	No	`true`	When supported, return only counties mapped to multiple income-limit areas.
`page / limit`	No	`1 / 10`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/fixed/il/map/counties?datasource=HUD&datasettype=Section8&fiscalyear=2026&stateabbr=CT&countyname=Fairfield&limit=10

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`stateabbr`	`CT`
`countyname`	`Fairfield`
`limit`	`10`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "stateabbr": "CT",
    "countyname": "Fairfield",
    "limit": 10,
    "page": 1
  },
  "metadata": {
    "resource": "fixed-il-map-counties",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 1
  },
  "data": [
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "areaMapCount": 16
    }
  ],
  "pagination": {
    "totalRecords": 1,
    "totalPages": 1,
    "currentPage": 1,
    "recordsPerPage": 10,
    "nextPage": null,
    "prevPage": null
  },
  "xRateLimit": {
    "period": "202606",
    "limit": null,
    "remaining": null,
    "reset": "2026-07-01T00:00:00.000Z",
    "unlimited": true
  }
}

Subcounty-to-Area Mapping

Returns expanded rows showing subcounty name, income-limit area ID, and income-limit area name.

GET /data/fixed/il/map/subcounties

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear / effectivedate`	No	`2026 / 2026-05-01`	Identify the released data set. `fiscalyear` matches an exact fiscal year; `effectivedate` resolves to the data set whose effective-date range contains the supplied date.
`statecode / stateabbr`	No	`09 / CT`	State filters.
`countycode / countyname`	No	`001 / Fairfield`	County filters.
`subcountyname`	No	`Bridgeport town`	Subcounty filter.
`splitcountiesonly`	No	`true`	When supported, return only counties mapped to multiple income-limit areas.
`page / limit`	No	`1 / 10`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/fixed/il/map/subcounties?datasource=HUD&datasettype=Section8&fiscalyear=2026&stateabbr=CT&countyname=Fairfield&limit=10

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`stateabbr`	`CT`
`countyname`	`Fairfield`
`limit`	`10`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "stateabbr": "CT",
    "countyname": "Fairfield",
    "limit": 10,
    "page": 1
  },
  "metadata": {
    "resource": "fixed-il-map-subcounties",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 10
  },
  "data": [
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyName": "Bethel town",
      "areaId": "METRO14860M14860",
      "areaName": "Bridgeport-Stamford-Danbury, CT MSA"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyName": "Bridgeport town",
      "areaId": "METRO14860M08070",
      "areaName": "Bridgeport town, CT Exception Area"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyName": "Brookfield town",
      "areaId": "METRO14860M14860",
      "areaName": "Bridgeport-Stamford-Danbury, CT MSA"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyName": "Danbury town",
      "areaId": "METRO14860M14860",
      "areaName": "Bridgeport-Stamford-Danbury, CT MSA"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyName": "Darien town",
      "areaId": "METRO14860M18850",
      "areaName": "Darien town, CT Exception Area"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyName": "Easton town",
      "areaId": "METRO14860M23890",
      "areaName": "Easton town, CT Exception Area"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyName": "Fairfield town",
      "areaId": "METRO14860M26620",
      "areaName": "Fairfield town, CT Exception Area"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyName": "Greenwich town",
      "areaId": "METRO14860M33620",
      "areaName": "Greenwich town, CT Exception Area"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyName": "Monroe town",
      "areaId": "METRO14860M48620",
      "areaName": "Monroe town, CT Exception Area"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyName": "New Canaan town",
      "areaId": "METRO14860M50580",
      "areaName": "New Canaan town, CT Exception Area"
    }
  ],
  "pagination": {
    "totalRecords": 23,
    "totalPages": 3,
    "currentPage": 1,
    "recordsPerPage": 10,
    "nextPage": 2,
    "prevPage": null
  },
  "xRateLimit": {
    "period": "202606",
    "limit": null,
    "remaining": null,
    "reset": "2026-07-01T00:00:00.000Z",
    "unlimited": true
  }
}

Collapsed Subcounty-to-Area Mapping

Returns area mapping rows with a collapsed subCountyList for each mapped area.

GET /data/fixed/il/map/subcounties/collapse

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear / effectivedate`	No	`2026 / 2026-05-01`	Identify the released data set. `fiscalyear` matches an exact fiscal year; `effectivedate` resolves to the data set whose effective-date range contains the supplied date.
`statecode / stateabbr`	No	`09 / CT`	State filters.
`countycode / countyname`	No	`001 / Fairfield`	County filters.
`subcountyname`	No	`Bridgeport town`	Subcounty filter.
`splitcountiesonly`	No	`true`	When supported, return only counties mapped to multiple income-limit areas.
`page / limit`	No	`1 / 10`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/fixed/il/map/subcounties/collapse?datasource=HUD&datasettype=Section8&fiscalyear=2026&stateabbr=CT&countyname=Fairfield&limit=10

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`stateabbr`	`CT`
`countyname`	`Fairfield`
`limit`	`10`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "stateabbr": "CT",
    "countyname": "Fairfield",
    "limit": 10,
    "page": 1
  },
  "metadata": {
    "resource": "fixed-il-map-subcounties-collapse",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 10
  },
  "data": [
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyList": [
        "Bridgeport town"
      ],
      "areaId": "METRO14860M08070",
      "areaName": "Bridgeport town, CT Exception Area"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyList": [
        "Easton town"
      ],
      "areaId": "METRO14860M23890",
      "areaName": "Easton town, CT Exception Area"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyList": [
        "Fairfield town"
      ],
      "areaId": "METRO14860M26620",
      "areaName": "Fairfield town, CT Exception Area"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyList": [
        "Monroe town"
      ],
      "areaId": "METRO14860M48620",
      "areaName": "Monroe town, CT Exception Area"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyList": [
        "Stratford town"
      ],
      "areaId": "METRO14860M74190",
      "areaName": "Stratford town, CT Exception Area"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyList": [
        "Trumbull town"
      ],
      "areaId": "METRO14860M77200",
      "areaName": "Trumbull town, CT Exception Area"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyList": [
        "Shelton town"
      ],
      "areaId": "METRO47930M47930",
      "areaName": "Waterbury-Shelton, CT MSA"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyList": [
        "Bethel town",
        "Brookfield town",
        "Danbury town",
        "New Fairfield town",
        "Newtown town",
        "Redding town",
        "Ridgefield town",
        "Sherman town"
      ],
      "areaId": "METRO14860M14860",
      "areaName": "Bridgeport-Stamford-Danbury, CT MSA"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyList": [
        "Darien town"
      ],
      "areaId": "METRO14860M18850",
      "areaName": "Darien town, CT Exception Area"
    },
    {
      "stateCode": "09",
      "stateAbbr": "CT",
      "countyCode": "001",
      "countyName": "Fairfield County",
      "subCountyList": [
        "Greenwich town"
      ],
      "areaId": "METRO14860M33620",
      "areaName": "Greenwich town, CT Exception Area"
    }
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Fixed Income Limits

Fixed income-limit endpoints return agency-published income limits and corresponding values. Lookup patterns include county, area, and state-level results.

Income Limits by County

Returns county-grouped areas with agency-published income-limit values.

GET /data/fixed/il/bycounty

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear / effectivedate`	No	`2026 / 2026-05-01`	Identify the released data set. `fiscalyear` matches an exact fiscal year; `effectivedate` resolves to the data set whose effective-date range contains the supplied date.
`statecode / stateabbr`	No	`36 / NY`	State filters.
`countycode / countyname`	No	`119 / Westchester`	County filters.
`subcountyname`	No	`All`	Subcounty filter.
`householdsize`	No	`4`	Filter returned limit values to a household size.
`limittype`	No	`80%`	Source-defined published limit type to return. Limit types may represent AMI bands, program income limits, median-income guideline values, or other published income-limit categories depending on the selected source data set.
`page / limit`	No	`1 / 1`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/fixed/il/bycounty?datasource=HUD&datasettype=Section8&fiscalyear=2026&stateabbr=NY&countyname=Westchester&limittype=80%&limit=1

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`stateabbr`	`NY`
`countyname`	`Westchester`
`limittype`	`80%`
`limit`	`1`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "stateabbr": "NY",
    "countyname": "Westchester",
    "limittype": "80%",
    "limit": 1,
    "page": 1
  },
  "metadata": {
    "resource": "fixed-il-groupby-county",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 1
  },
  "data": [
    {
      "stateCode": "36",
      "stateAbbr": "NY",
      "countyCode": "119",
      "countyName": "Westchester County",
      "areas": [
        {
          "id": "METRO48325M48325",
          "mfi": 164200,
          "name": "Westchester County, NY Statutory Exception Area",
          "subCounty": [
            "All"
          ],
          "incomeLimits": [
            {
              "limitType": "80%",
              "limitValues": [
                {
                  "incomeLimit": 88100,
                  "householdSize": 1
                },
                {
                  "incomeLimit": 100700,
                  "householdSize": 2
                },
                {
                  "incomeLimit": 113300,
                  "householdSize": 3
                },
                {
                  "incomeLimit": 125850,
                  "householdSize": 4
                },
                {
                  "incomeLimit": 135950,
                  "householdSize": 5
                },
                {
                  "incomeLimit": 146000,
                  "householdSize": 6
                },
                {
                  "incomeLimit": 156100,
                  "householdSize": 7
                },
                {
                  "incomeLimit": 166150,
                  "householdSize": 8
                }
              ]
            }
          ]
        }
      ]
    }
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}

County Lookup Areas Only

Returns the county-grouped lookup structure and mapped areas without income-limit values.

GET /data/fixed/il/bycounty/map

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear / effectivedate`	No	`2026 / 2026-05-01`	Identify the released data set. `fiscalyear` matches an exact fiscal year; `effectivedate` resolves to the data set whose effective-date range contains the supplied date.
`statecode / stateabbr`	No	`36 / NY`	State filters.
`countycode / countyname`	No	`119 / Westchester`	County filters.
`subcountyname`	No	`All`	Subcounty filter.
`page / limit`	No	`1 / 1`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/fixed/il/bycounty/map?datasource=HUD&datasettype=Section8&fiscalyear=2026&stateabbr=NY&countyname=Westchester&limit=1

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`stateabbr`	`NY`
`countyname`	`Westchester`
`limit`	`1`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "stateabbr": "NY",
    "countyname": "Westchester",
    "limit": 1,
    "page": 1
  },
  "metadata": {
    "resource": "fixed-il-groupby-county-maponly",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 1
  },
  "data": [
    {
      "stateCode": "36",
      "stateAbbr": "NY",
      "countyCode": "119",
      "countyName": "Westchester County",
      "areas": [
        {
          "id": "METRO48325M48325",
          "name": "Westchester County, NY Statutory Exception Area",
          "subCounty": [
            "All"
          ]
        }
      ]
    }
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}

Income Limits by Area

Returns area-grouped limits with counties included in each area.

GET /data/fixed/il/byarea

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear / effectivedate`	No	`2026 / 2026-05-01`	Identify the released data set. `fiscalyear` matches an exact fiscal year; `effectivedate` resolves to the data set whose effective-date range contains the supplied date.
`statecode / stateabbr`	No	`36 / NY`	State filters.
`countycode / countyname`	No	`119 / Westchester`	County filters.
`subcountyname`	No	`All`	Subcounty filter.
`areaid / areaname`	No	`METRO48325M48325 / Westchester County`	Income-limit area filters.
`householdsize`	No	`4`	Filter returned limit values to a household size.
`limittype`	No	`80%`	Source-defined published limit type to return. Limit types may represent AMI bands, program income limits, median-income guideline values, or other published income-limit categories depending on the selected source data set.
`page / limit`	No	`1 / 1`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/fixed/il/byarea?datasource=HUD&datasettype=Section8&fiscalyear=2026&stateabbr=NY&countyname=Westchester&limittype=80%&limit=1

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`stateabbr`	`NY`
`countyname`	`Westchester`
`limittype`	`80%`
`limit`	`1`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "stateabbr": "NY",
    "countyname": "Westchester",
    "limittype": "80%",
    "limit": 1,
    "page": 1
  },
  "metadata": {
    "resource": "fixed-il-groupby-area",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 1
  },
  "data": [
    {
      "id": "METRO48325M48325",
      "mfi": 164200,
      "name": "Westchester County, NY Statutory Exception Area",
      "counties": [
        {
          "stateAbbr": "NY",
          "stateCode": "36",
          "subCounty": [
            "All"
          ],
          "countyCode": "119",
          "countyName": "Westchester County"
        }
      ],
      "incomeLimits": [
        {
          "limitType": "80%",
          "limitValues": [
            {
              "incomeLimit": 88100,
              "householdSize": 1
            },
            {
              "incomeLimit": 100700,
              "householdSize": 2
            },
            {
              "incomeLimit": 113300,
              "householdSize": 3
            },
            {
              "incomeLimit": 125850,
              "householdSize": 4
            },
            {
              "incomeLimit": 135950,
              "householdSize": 5
            },
            {
              "incomeLimit": 146000,
              "householdSize": 6
            },
            {
              "incomeLimit": 156100,
              "householdSize": 7
            },
            {
              "incomeLimit": 166150,
              "householdSize": 8
            }
          ]
        }
      ]
    }
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}

Area Lookup Counties Only

Returns area-to-county lookup structure without income-limit values.

GET /data/fixed/il/byarea/map

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear / effectivedate`	No	`2026 / 2026-05-01`	Identify the released data set. `fiscalyear` matches an exact fiscal year; `effectivedate` resolves to the data set whose effective-date range contains the supplied date.
`statecode / stateabbr`	No	`36 / NY`	State filters.
`countycode / countyname`	No	`119 / Westchester`	County filters.
`subcountyname`	No	`All`	Subcounty filter.
`areaid / areaname`	No	`METRO48325M48325 / Westchester County`	Income-limit area filters.
`page / limit`	No	`1 / 1`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/fixed/il/byarea/map?datasource=HUD&datasettype=Section8&fiscalyear=2026&stateabbr=NY&countyname=Westchester&limit=1

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`stateabbr`	`NY`
`countyname`	`Westchester`
`limit`	`1`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "stateabbr": "NY",
    "countyname": "Westchester",
    "limit": 1,
    "page": 1
  },
  "metadata": {
    "resource": "fixed-il-groupby-area-maponly",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 1
  },
  "data": [
    {
      "id": "METRO48325M48325",
      "name": "Westchester County, NY Statutory Exception Area",
      "counties": [
        {
          "stateAbbr": "NY",
          "stateCode": "36",
          "subCounty": [
            "All"
          ],
          "countyCode": "119",
          "countyName": "Westchester County"
        }
      ]
    }
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}

State-Level Limits

Returns state-level fixed income limits where available.

GET /data/fixed/il/state-limits

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear / effectivedate`	No	`2026 / 2026-05-01`	Identify the released data set. `fiscalyear` matches an exact fiscal year; `effectivedate` resolves to the data set whose effective-date range contains the supplied date.
`statecode / stateabbr`	No	`36 / NY`	State filters.
`householdsize`	No	`4`	Filter returned limit values to a household size.
`limittype`	No	`80%`	Source-defined published limit type to return. Limit types may represent AMI bands, program income limits, median-income guideline values, or other published income-limit categories depending on the selected source data set.
`page / limit`	No	`1 / 10`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/fixed/il/state-limits?datasource=HUD&datasettype=Section8&fiscalyear=2026&limittype=80%&limit=10

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`limittype`	`80%`
`limit`	`10`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "limittype": "80%",
    "limit": 10,
    "page": 1
  },
  "metadata": {
    "resource": "fixed-il-state-limits",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 10
  },
  "data": [
    [
      {
        "mfi": 120300,
        "stateAbbr": "AK",
        "stateCode": "02",
        "stateName": "Alaska",
        "incomeLimits": [
          {
            "limitType": "80%",
            "limitValues": [
              {
                "incomeLimit": 67400,
                "householdSize": 1
              },
              {
                "incomeLimit": 77000,
                "householdSize": 2
              },
              {
                "incomeLimit": 86650,
                "householdSize": 3
              },
              {
                "incomeLimit": 96250,
                "householdSize": 4
              },
              {
                "incomeLimit": 103950,
                "householdSize": 5
              },
              {
                "incomeLimit": 111650,
                "householdSize": 6
              },
              {
                "incomeLimit": 119350,
                "householdSize": 7
              },
              {
                "incomeLimit": 127050,
                "householdSize": 8
              }
            ]
          }
        ]
      }
    ]
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Derived Income Limits

Derived income limit endpoints are part of Finbase derived data and calculate requested percentage-based income limits from agency-published fixed income-limit values. Depending on the selected source data set, baseline values may represent AMI limits, program income limits, median-income guideline values, or other source-defined income-limit categories.

Calculated value precision: Derived income-limit outputs return two-decimal calculated values for income-limit and rent calculations. Use roundingmode=round or omit the parameter for normal rounding. Use roundingmode=truncate when conservative two-decimal truncation is required. Fixed income-limit endpoints are unaffected because they return source-published values rather than calculated values.

Derived Income Limits by County

Returns county-grouped income limits derived from a baseline published limit type and requested target percentages.

GET /data/derived/il/target-ami-max-income/bycounty

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`limittype`	Yes	`80%`	Baseline published limit type from the selected source data set. Limit types are source-defined and may represent AMI bands, program income limits, median-income guideline values, or other published income-limit categories.
`targetamis`	Yes	`80,120`	Comma-separated target percentages to calculate from the selected baseline limit type. For HUD-style data sets, these commonly correspond to AMI percentages. For other source data sets, they represent calculated percentages of the source-defined published limit.
`roundingmode`	No	`round`	Final two-decimal handling for calculated values. Supported values are `round` (default normal rounding), `truncate` (conservative truncation), and `trunc` (accepted shorthand for `truncate`).
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear / effectivedate`	No	`2026 / 2026-05-01`	Identify the released data set. `fiscalyear` matches an exact fiscal year; `effectivedate` resolves to the data set whose effective-date range contains the supplied date.
`statecode / stateabbr`	No	`36 / NY`	State filters.
`countycode / countyname`	No	`119 / Westchester`	County filters.
`subcountyname`	No	`All`	Subcounty filter.
`householdsize`	No	`4`	Filter returned values to a household size.
`page / limit`	No	`1 / 1`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/derived/il/target-ami-max-income/bycounty?datasource=HUD&datasettype=Section8&fiscalyear=2026&stateabbr=NY&countyname=Westchester&limittype=80%&targetamis=80,120&limit=1

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`stateabbr`	`NY`
`countyname`	`Westchester`
`limittype`	`80%`
`targetamis`	`80,120`
`limit`	`1`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "stateabbr": "NY",
    "countyname": "Westchester",
    "limittype": "80%",
    "targetamis": "80,120",
    "limit": 1,
    "page": 1
  },
  "metadata": {
    "resource": "derived-il-ami-max-income-groupby-county",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 1
  },
  "data": [
    {
      "stateCode": "36",
      "stateAbbr": "NY",
      "countyCode": "119",
      "countyName": "Westchester County",
      "areas": [
        {
          "id": "METRO48325M48325",
          "mfi": 164200,
          "name": "Westchester County, NY Statutory Exception Area",
          "subCounty": [
            "All"
          ],
          "incomeLimits": [
            {
              "limitType": "80%",
              "limitValues": [
                {
                  "incomeLimit": 88100,
                  "householdSize": 1
                },
                {
                  "incomeLimit": 100700,
                  "householdSize": 2
                },
                {
                  "incomeLimit": 113300,
                  "householdSize": 3
                },
                {
                  "incomeLimit": 125850,
                  "householdSize": 4
                },
                {
                  "incomeLimit": 135950,
                  "householdSize": 5
                },
                {
                  "incomeLimit": 146000,
                  "householdSize": 6
                },
                {
                  "incomeLimit": 156100,
                  "householdSize": 7
                },
                {
                  "incomeLimit": 166150,
                  "householdSize": 8
                }
              ]
            }
          ],
          "derivedLimits": [
            {
              "limitType": "80%",
              "limitValues": [
                {
                  "householdSize": 1,
                  "incomeLimit": 88100
                },
                {
                  "householdSize": 2,
                  "incomeLimit": 100700
                },
                {
                  "householdSize": 3,
                  "incomeLimit": 113300
                },
                {
                  "householdSize": 4,
                  "incomeLimit": 125850
                },
                {
                  "householdSize": 5,
                  "incomeLimit": 135950
                },
                {
                  "householdSize": 6,
                  "incomeLimit": 146000
                },
                {
                  "householdSize": 7,
                  "incomeLimit": 156100
                },
                {
                  "householdSize": 8,
                  "incomeLimit": 166150
                }
              ]
            },
            {
              "limitType": "120%",
              "limitValues": [
                {
                  "householdSize": 1,
                  "incomeLimit": 132150
                },
                {
                  "householdSize": 2,
                  "incomeLimit": 151050
                },
                {
                  "householdSize": 3,
                  "incomeLimit": 169950
                },
                {
                  "householdSize": 4,
                  "incomeLimit": 188775
                },
                {
                  "householdSize": 5,
                  "incomeLimit": 203925
                },
                {
                  "householdSize": 6,
                  "incomeLimit": 219000
                },
                {
                  "householdSize": 7,
                  "incomeLimit": 234150
                },
                {
                  "householdSize": 8,
                  "incomeLimit": 249225
                }
              ]
            }
          ]
        }
      ]
    }
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Derived Income Limits by Area

Returns area-grouped income limits derived from a baseline published limit type and requested target percentages.

GET /data/derived/il/target-ami-max-income/byarea

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`limittype`	Yes	`80%`	Baseline published limit type from the selected source data set. Limit types are source-defined and may represent AMI bands, program income limits, median-income guideline values, or other published income-limit categories.
`targetamis`	Yes	`80,120`	Comma-separated target percentages to calculate from the selected baseline limit type. For HUD-style data sets, these commonly correspond to AMI percentages. For other source data sets, they represent calculated percentages of the source-defined published limit.
`roundingmode`	No	`round`	Final two-decimal handling for calculated values. Supported values are `round` (default normal rounding), `truncate` (conservative truncation), and `trunc` (accepted shorthand for `truncate`).
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear / effectivedate`	No	`2026 / 2026-05-01`	Identify the released data set. `fiscalyear` matches an exact fiscal year; `effectivedate` resolves to the data set whose effective-date range contains the supplied date.
`statecode / stateabbr`	No	`36 / NY`	State filters.
`countycode / countyname`	No	`119 / Westchester`	County filters.
`subcountyname`	No	`All`	Subcounty filter.
`areaid / areaname`	No	`METRO48325M48325 / Westchester County`	Income-limit area filters.
`householdsize`	No	`4`	Filter returned values to a household size.
`page / limit`	No	`1 / 1`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/derived/il/target-ami-max-income/byarea?datasource=HUD&datasettype=Section8&fiscalyear=2026&stateabbr=NY&countyname=Westchester&limittype=80%&targetamis=80,120&limit=1

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`stateabbr`	`NY`
`countyname`	`Westchester`
`limittype`	`80%`
`targetamis`	`80,120`
`limit`	`1`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "stateabbr": "NY",
    "countyname": "Westchester",
    "limittype": "80%",
    "targetamis": "80,120",
    "limit": 1,
    "page": 1
  },
  "metadata": {
    "resource": "derived-il-ami-max-income-groupby-area",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 1
  },
  "data": [
    {
      "id": "METRO48325M48325",
      "mfi": 164200,
      "name": "Westchester County, NY Statutory Exception Area",
      "counties": [
        {
          "stateAbbr": "NY",
          "stateCode": "36",
          "subCounty": [
            "All"
          ],
          "countyCode": "119",
          "countyName": "Westchester County"
        }
      ],
      "incomeLimits": [
        {
          "limitType": "80%",
          "limitValues": [
            {
              "incomeLimit": 88100,
              "householdSize": 1
            },
            {
              "incomeLimit": 100700,
              "householdSize": 2
            },
            {
              "incomeLimit": 113300,
              "householdSize": 3
            },
            {
              "incomeLimit": 125850,
              "householdSize": 4
            },
            {
              "incomeLimit": 135950,
              "householdSize": 5
            },
            {
              "incomeLimit": 146000,
              "householdSize": 6
            },
            {
              "incomeLimit": 156100,
              "householdSize": 7
            },
            {
              "incomeLimit": 166150,
              "householdSize": 8
            }
          ]
        }
      ],
      "derivedLimits": [
        {
          "limitType": "80%",
          "limitValues": [
            {
              "householdSize": 1,
              "incomeLimit": 88100
            },
            {
              "householdSize": 2,
              "incomeLimit": 100700
            },
            {
              "householdSize": 3,
              "incomeLimit": 113300
            },
            {
              "householdSize": 4,
              "incomeLimit": 125850
            },
            {
              "householdSize": 5,
              "incomeLimit": 135950
            },
            {
              "householdSize": 6,
              "incomeLimit": 146000
            },
            {
              "householdSize": 7,
              "incomeLimit": 156100
            },
            {
              "householdSize": 8,
              "incomeLimit": 166150
            }
          ]
        },
        {
          "limitType": "120%",
          "limitValues": [
            {
              "householdSize": 1,
              "incomeLimit": 132150
            },
            {
              "householdSize": 2,
              "incomeLimit": 151050
            },
            {
              "householdSize": 3,
              "incomeLimit": 169950
            },
            {
              "householdSize": 4,
              "incomeLimit": 188775
            },
            {
              "householdSize": 5,
              "incomeLimit": 203925
            },
            {
              "householdSize": 6,
              "incomeLimit": 219000
            },
            {
              "householdSize": 7,
              "incomeLimit": 234150
            },
            {
              "householdSize": 8,
              "incomeLimit": 249225
            }
          ]
        }
      ]
    }
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}

Derived State-Level Income Limits

Returns state-level derived income limits where available.

GET /data/derived/il/target-ami-max-income/state-limits

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`limittype`	Yes	`80%`	Baseline published limit type from the selected source data set. Limit types are source-defined and may represent AMI bands, program income limits, median-income guideline values, or other published income-limit categories.
`targetamis`	Yes	`80,120`	Comma-separated target percentages to calculate from the selected baseline limit type. For HUD-style data sets, these commonly correspond to AMI percentages. For other source data sets, they represent calculated percentages of the source-defined published limit.
`roundingmode`	No	`round`	Final two-decimal handling for calculated values. Supported values are `round` (default normal rounding), `truncate` (conservative truncation), and `trunc` (accepted shorthand for `truncate`).
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear / effectivedate`	No	`2026 / 2026-05-01`	Identify the released data set. `fiscalyear` matches an exact fiscal year; `effectivedate` resolves to the data set whose effective-date range contains the supplied date.
`statecode / stateabbr`	No	`36 / NY`	State filters.
`householdsize`	No	`4`	Filter returned values to a household size.
`page / limit`	No	`1 / 1`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/derived/il/target-ami-max-income/state-limits?datasource=HUD&datasettype=Section8&fiscalyear=2026&stateabbr=NY&limittype=80%&targetamis=80,120&limit=1

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`stateabbr`	`NY`
`limittype`	`80%`
`targetamis`	`80,120`
`limit`	`1`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "stateabbr": "NY",
    "limittype": "80%",
    "targetamis": "80,120",
    "limit": 1,
    "page": 1
  },
  "metadata": {
    "resource": "derived-il-ami-max-income-state-limits",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 1
  },
  "data": [
    {
      "mfi": 111900,
      "stateAbbr": "NY",
      "stateCode": "36",
      "stateName": "New York",
      "incomeLimits": [
        {
          "limitType": "80%",
          "limitValues": [
            {
              "incomeLimit": 62650,
              "householdSize": 1
            },
            {
              "incomeLimit": 71600,
              "householdSize": 2
            },
            {
              "incomeLimit": 80550,
              "householdSize": 3
            },
            {
              "incomeLimit": 89500,
              "householdSize": 4
            },
            {
              "incomeLimit": 96700,
              "householdSize": 5
            },
            {
              "incomeLimit": 103850,
              "householdSize": 6
            },
            {
              "incomeLimit": 111000,
              "householdSize": 7
            },
            {
              "incomeLimit": 118150,
              "householdSize": 8
            }
          ]
        }
      ],
      "derivedLimits": [
        {
          "limitType": "80%",
          "limitValues": [
            {
              "householdSize": 1,
              "incomeLimit": 62650
            },
            {
              "householdSize": 2,
              "incomeLimit": 71600
            },
            {
              "householdSize": 3,
              "incomeLimit": 80550
            },
            {
              "householdSize": 4,
              "incomeLimit": 89500
            },
            {
              "householdSize": 5,
              "incomeLimit": 96700
            },
            {
              "householdSize": 6,
              "incomeLimit": 103850
            },
            {
              "householdSize": 7,
              "incomeLimit": 111000
            },
            {
              "householdSize": 8,
              "incomeLimit": 118150
            }
          ]
        },
        {
          "limitType": "120%",
          "limitValues": [
            {
              "householdSize": 1,
              "incomeLimit": 93975
            },
            {
              "householdSize": 2,
              "incomeLimit": 107400
            },
            {
              "householdSize": 3,
              "incomeLimit": 120825
            },
            {
              "householdSize": 4,
              "incomeLimit": 134250
            },
            {
              "householdSize": 5,
              "incomeLimit": 145050
            },
            {
              "householdSize": 6,
              "incomeLimit": 155775
            },
            {
              "householdSize": 7,
              "incomeLimit": 166500
            },
            {
              "householdSize": 8,
              "incomeLimit": 177225
            }
          ]
        }
      ]
    }
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}

Rent Limits

Rent limit endpoints are part of Finbase derived data. They calculate rent limits from source-defined income-limit data using requested target percentages, affordability percentages, and optional bedroom-size outputs.

Rent calculation precision: Rent limit endpoints return two-decimal calculated values for income-limit and rent calculations. The selected roundingmode applies to calculated income-limit values and calculated rent values returned by these endpoints.

Rent Limits by County

Returns county-grouped rent limits by household size.

GET /data/derived/il/target-ami-max-rent/bycounty

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`limittype`	Yes	`50%`	Baseline published limit type from the selected source data set. Limit types are source-defined and may represent AMI bands, program income limits, median-income guideline values, or other published income-limit categories.
`targetamis`	Yes	`50,60,80`	Comma-separated target percentages to calculate from the selected baseline limit type. For HUD-style data sets, these commonly correspond to AMI percentages. For other source data sets, they represent calculated percentages of the source-defined published limit.
`roundingmode`	No	`round`	Final two-decimal handling for calculated values. Supported values are `round` (default normal rounding), `truncate` (conservative truncation), and `trunc` (accepted shorthand for `truncate`).
`expenselimit`	No	`30%`	Affordability or expense percentage used in rent calculation.
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear / effectivedate`	No	`2026 / 2026-05-01`	Identify the released data set. `fiscalyear` matches an exact fiscal year; `effectivedate` resolves to the data set whose effective-date range contains the supplied date.
`statecode / stateabbr`	No	`36 / NY`	State filters.
`countycode / countyname`	No	`119 / Westchester`	County filters.
`subcountyname`	No	`All`	Subcounty filter.
`householdsize`	No	`4`	Filter returned values to a household size.
`page / limit`	No	`1 / 1`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/derived/il/target-ami-max-rent/bycounty?datasource=HUD&datasettype=Section8&fiscalyear=2026&stateabbr=NY&countyname=Westchester&limittype=50%&targetamis=50,60,80&expenselimit=30%&limit=1

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`stateabbr`	`NY`
`countyname`	`Westchester`
`limittype`	`50%`
`targetamis`	`50,60,80`
`expenselimit`	`30%`
`limit`	`1`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "stateabbr": "NY",
    "countyname": "Westchester",
    "limittype": "50%",
    "targetamis": "50,60,80",
    "expenselimit": "30%",
    "limit": 1,
    "page": 1
  },
  "metadata": {
    "resource": "derived-il-ami-max-rent-groupby-county",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 1
  },
  "data": [
    {
      "stateCode": "36",
      "stateAbbr": "NY",
      "countyCode": "119",
      "countyName": "Westchester County",
      "areas": [
        {
          "id": "METRO48325M48325",
          "mfi": 164200,
          "name": "Westchester County, NY Statutory Exception Area",
          "subCounty": [
            "All"
          ],
          "incomeLimits": [
            {
              "limitType": "50%",
              "limitValues": [
                {
                  "incomeLimit": 59400,
                  "householdSize": 1
                },
                {
                  "incomeLimit": 67850,
                  "householdSize": 2
                },
                {
                  "incomeLimit": 76350,
                  "householdSize": 3
                },
                {
                  "incomeLimit": 84800,
                  "householdSize": 4
                },
                {
                  "incomeLimit": 91600,
                  "householdSize": 5
                },
                {
                  "incomeLimit": 98400,
                  "householdSize": 6
                },
                {
                  "incomeLimit": 105200,
                  "householdSize": 7
                },
                {
                  "incomeLimit": 111950,
                  "householdSize": 8
                }
              ]
            }
          ],
          "derivedLimits": [
            {
              "limitType": "50%",
              "limitValues": [
                {
                  "householdSize": 1,
                  "incomeLimit": 59400,
                  "rentLimit": 1485
                },
                {
                  "householdSize": 2,
                  "incomeLimit": 67850,
                  "rentLimit": 1696.25
                },
                {
                  "householdSize": 3,
                  "incomeLimit": 76350,
                  "rentLimit": 1908.75
                },
                {
                  "householdSize": 4,
                  "incomeLimit": 84800,
                  "rentLimit": 2120
                },
                {
                  "householdSize": 5,
                  "incomeLimit": 91600,
                  "rentLimit": 2290
                },
                {
                  "householdSize": 6,
                  "incomeLimit": 98400,
                  "rentLimit": 2460
                },
                {
                  "householdSize": 7,
                  "incomeLimit": 105200,
                  "rentLimit": 2630
                },
                {
                  "householdSize": 8,
                  "incomeLimit": 111950,
                  "rentLimit": 2798.75
                }
              ]
            },
            {
              "limitType": "60%",
              "limitValues": [
                {
                  "householdSize": 1,
                  "incomeLimit": 71280,
                  "rentLimit": 1782
                },
                {
                  "householdSize": 2,
                  "incomeLimit": 81420,
                  "rentLimit": 2035.5
                },
                {
                  "householdSize": 3,
                  "incomeLimit": 91620,
                  "rentLimit": 2290.5
                },
                {
                  "householdSize": 4,
                  "incomeLimit": 101760,
                  "rentLimit": 2544
                },
                {
                  "householdSize": 5,
                  "incomeLimit": 109920,
                  "rentLimit": 2748
                },
                {
                  "householdSize": 6,
                  "incomeLimit": 118080,
                  "rentLimit": 2952
                },
                {
                  "householdSize": 7,
                  "incomeLimit": 126240,
                  "rentLimit": 3156
                },
                {
                  "householdSize": 8,
                  "incomeLimit": 134340,
                  "rentLimit": 3358.5
                }
              ]
            },
            {
              "limitType": "80%",
              "limitValues": [
                {
                  "householdSize": 1,
                  "incomeLimit": 95040,
                  "rentLimit": 2376
                },
                {
                  "householdSize": 2,
                  "incomeLimit": 108560,
                  "rentLimit": 2714
                },
                {
                  "householdSize": 3,
                  "incomeLimit": 122160,
                  "rentLimit": 3054
                },
                {
                  "householdSize": 4,
                  "incomeLimit": 135680,
                  "rentLimit": 3392
                },
                {
                  "householdSize": 5,
                  "incomeLimit": 146560,
                  "rentLimit": 3664
                },
                {
                  "householdSize": 6,
                  "incomeLimit": 157440,
                  "rentLimit": 3936
                },
                {
                  "householdSize": 7,
                  "incomeLimit": 168320,
                  "rentLimit": 4208
                },
                {
                  "householdSize": 8,
                  "incomeLimit": 179120,
                  "rentLimit": 4478
                }
              ]
            }
          ]
        }
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Rent Limits by County and Bedroom Size

Returns county-grouped rent limits by bedroom size.

GET /data/derived/il/target-ami-max-rent/bycounty/bybedroomsize

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`limittype`	Yes	`50%`	Baseline published limit type from the selected source data set. Limit types are source-defined and may represent AMI bands, program income limits, median-income guideline values, or other published income-limit categories.
`targetamis`	Yes	`50,60,80`	Comma-separated target percentages to calculate from the selected baseline limit type. For HUD-style data sets, these commonly correspond to AMI percentages. For other source data sets, they represent calculated percentages of the source-defined published limit.
`roundingmode`	No	`round`	Final two-decimal handling for calculated values. Supported values are `round` (default normal rounding), `truncate` (conservative truncation), and `trunc` (accepted shorthand for `truncate`).
`expenselimit`	No	`30%`	Affordability or expense percentage used in rent calculation.
`bedroomsize`	No	`2`	Filter to a bedroom size.
`bedroomsizefactor`	No	`1.5`	Factor used to derive household size from bedroom size.
`roundhouseholdsize`	No	`true`	Controls household-size rounding behavior where supported.
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear / effectivedate`	No	`2026 / 2026-05-01`	Identify the released data set. `fiscalyear` matches an exact fiscal year; `effectivedate` resolves to the data set whose effective-date range contains the supplied date.
`statecode / stateabbr`	No	`36 / NY`	State filters.
`countycode / countyname`	No	`119 / Westchester`	County filters.
`subcountyname`	No	`All`	Subcounty filter.
`page / limit`	No	`1 / 1`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/derived/il/target-ami-max-rent/bycounty/bybedroomsize?datasource=HUD&datasettype=Section8&fiscalyear=2026&stateabbr=NY&countyname=Westchester&limittype=50%&targetamis=50,60,80&expenselimit=30%&bedroomsizefactor=1.5&limit=1

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`stateabbr`	`NY`
`countyname`	`Westchester`
`limittype`	`50%`
`targetamis`	`50,60,80`
`expenselimit`	`30%`
`bedroomsizefactor`	`1.5`
`limit`	`1`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "stateabbr": "NY",
    "countyname": "Westchester",
    "limittype": "50%",
    "targetamis": "50,60,80",
    "expenselimit": "30%",
    "bedroomsizefactor": 1.5,
    "limit": 1,
    "page": 1
  },
  "metadata": {
    "resource": "derived-il-ami-max-rent-groupby-county-outputby-bedroomsize",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 1
  },
  "data": [
    {
      "stateCode": "36",
      "stateAbbr": "NY",
      "countyCode": "119",
      "countyName": "Westchester County",
      "areas": [
        {
          "id": "METRO48325M48325",
          "mfi": 164200,
          "name": "Westchester County, NY Statutory Exception Area",
          "subCounty": [
            "All"
          ],
          "incomeLimits": [
            {
              "limitType": "50%",
              "limitValues": [
                {
                  "incomeLimit": 59400,
                  "householdSize": 1
                },
                {
                  "incomeLimit": 67850,
                  "householdSize": 2
                },
                {
                  "incomeLimit": 76350,
                  "householdSize": 3
                },
                {
                  "incomeLimit": 84800,
                  "householdSize": 4
                },
                {
                  "incomeLimit": 91600,
                  "householdSize": 5
                },
                {
                  "incomeLimit": 98400,
                  "householdSize": 6
                },
                {
                  "incomeLimit": 105200,
                  "householdSize": 7
                },
                {
                  "incomeLimit": 111950,
                  "householdSize": 8
                }
              ]
            }
          ],
          "derivedLimits": [
            {
              "limitType": "50%",
              "limitValues": [
                {
                  "bedroomSize": 0,
                  "householdSize": 1,
                  "incomeLimit": 59400,
                  "rentLimit": 1485
                },
                {
                  "bedroomSize": 1,
                  "householdSize": 1.5,
                  "incomeLimit": 63625,
                  "rentLimit": 1590.62
                },
                {
                  "bedroomSize": 2,
                  "householdSize": 3,
                  "incomeLimit": 76350,
                  "rentLimit": 1908.75
                },
                {
                  "bedroomSize": 3,
                  "householdSize": 4.5,
                  "incomeLimit": 88200,
                  "rentLimit": 2205
                },
                {
                  "bedroomSize": 4,
                  "householdSize": 6,
                  "incomeLimit": 98400,
                  "rentLimit": 2460
                }
              ]
            },
            {
              "limitType": "60%",
              "limitValues": [
                {
                  "bedroomSize": 0,
                  "householdSize": 1,
                  "incomeLimit": 71280,
                  "rentLimit": 1782
                },
                {
                  "bedroomSize": 1,
                  "householdSize": 1.5,
                  "incomeLimit": 76350,
                  "rentLimit": 1908.75
                },
                {
                  "bedroomSize": 2,
                  "householdSize": 3,
                  "incomeLimit": 91620,
                  "rentLimit": 2290.5
                },
                {
                  "bedroomSize": 3,
                  "householdSize": 4.5,
                  "incomeLimit": 105840,
                  "rentLimit": 2646
                },
                {
                  "bedroomSize": 4,
                  "householdSize": 6,
                  "incomeLimit": 118080,
                  "rentLimit": 2952
                }
              ]
            },
            {
              "limitType": "80%",
              "limitValues": [
                {
                  "bedroomSize": 0,
                  "householdSize": 1,
                  "incomeLimit": 95040,
                  "rentLimit": 2376
                },
                {
                  "bedroomSize": 1,
                  "householdSize": 1.5,
                  "incomeLimit": 101800,
                  "rentLimit": 2545
                },
                {
                  "bedroomSize": 2,
                  "householdSize": 3,
                  "incomeLimit": 122160,
                  "rentLimit": 3054
                },
                {
                  "bedroomSize": 3,
                  "householdSize": 4.5,
                  "incomeLimit": 141120,
                  "rentLimit": 3528
                },
                {
                  "bedroomSize": 4,
                  "householdSize": 6,
                  "incomeLimit": 157440,
                  "rentLimit": 3936
                }
              ]
            }
          ]
        }
      ]
    }
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}

Rent Limits by Area

Returns area-grouped rent limits by household size.

GET /data/derived/il/target-ami-max-rent/byarea

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`limittype`	Yes	`50%`	Baseline published limit type from the selected source data set. Limit types are source-defined and may represent AMI bands, program income limits, median-income guideline values, or other published income-limit categories.
`targetamis`	Yes	`50,60,80`	Comma-separated target percentages to calculate from the selected baseline limit type. For HUD-style data sets, these commonly correspond to AMI percentages. For other source data sets, they represent calculated percentages of the source-defined published limit.
`roundingmode`	No	`round`	Final two-decimal handling for calculated values. Supported values are `round` (default normal rounding), `truncate` (conservative truncation), and `trunc` (accepted shorthand for `truncate`).
`expenselimit`	No	`30%`	Affordability or expense percentage used in rent calculation.
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear / effectivedate`	No	`2026 / 2026-05-01`	Identify the released data set. `fiscalyear` matches an exact fiscal year; `effectivedate` resolves to the data set whose effective-date range contains the supplied date.
`statecode / stateabbr`	No	`36 / NY`	State filters.
`countycode / countyname`	No	`119 / Westchester`	County filters.
`subcountyname`	No	`All`	Subcounty filter.
`areaid / areaname`	No	`METRO48325M48325 / Westchester County`	Income-limit area filters.
`householdsize`	No	`4`	Filter returned values to a household size.
`page / limit`	No	`1 / 1`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/derived/il/target-ami-max-rent/byarea?datasource=HUD&datasettype=Section8&fiscalyear=2026&stateabbr=NY&countyname=Westchester&limittype=50%&targetamis=50,60,80&expenselimit=30%&limit=1

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`stateabbr`	`NY`
`countyname`	`Westchester`
`limittype`	`50%`
`targetamis`	`50,60,80`
`expenselimit`	`30%`
`limit`	`1`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "stateabbr": "NY",
    "countyname": "Westchester",
    "limittype": "50%",
    "targetamis": "50,60,80",
    "expenselimit": "30%",
    "limit": 1,
    "page": 1
  },
  "metadata": {
    "resource": "derived-il-ami-max-rent-groupby-area",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 1
  },
  "data": [
    {
      "id": "METRO48325M48325",
      "mfi": 164200,
      "name": "Westchester County, NY Statutory Exception Area",
      "counties": [
        {
          "stateAbbr": "NY",
          "stateCode": "36",
          "subCounty": [
            "All"
          ],
          "countyCode": "119",
          "countyName": "Westchester County"
        }
      ],
      "incomeLimits": [
        {
          "limitType": "50%",
          "limitValues": [
            {
              "incomeLimit": 59400,
              "householdSize": 1
            },
            {
              "incomeLimit": 67850,
              "householdSize": 2
            },
            {
              "incomeLimit": 76350,
              "householdSize": 3
            },
            {
              "incomeLimit": 84800,
              "householdSize": 4
            },
            {
              "incomeLimit": 91600,
              "householdSize": 5
            },
            {
              "incomeLimit": 98400,
              "householdSize": 6
            },
            {
              "incomeLimit": 105200,
              "householdSize": 7
            },
            {
              "incomeLimit": 111950,
              "householdSize": 8
            }
          ]
        }
      ],
      "derivedLimits": [
        {
          "limitType": "50%",
          "limitValues": [
            {
              "householdSize": 1,
              "incomeLimit": 59400,
              "rentLimit": 1485
            },
            {
              "householdSize": 2,
              "incomeLimit": 67850,
              "rentLimit": 1696.25
            },
            {
              "householdSize": 3,
              "incomeLimit": 76350,
              "rentLimit": 1908.75
            },
            {
              "householdSize": 4,
              "incomeLimit": 84800,
              "rentLimit": 2120
            },
            {
              "householdSize": 5,
              "incomeLimit": 91600,
              "rentLimit": 2290
            },
            {
              "householdSize": 6,
              "incomeLimit": 98400,
              "rentLimit": 2460
            },
            {
              "householdSize": 7,
              "incomeLimit": 105200,
              "rentLimit": 2630
            },
            {
              "householdSize": 8,
              "incomeLimit": 111950,
              "rentLimit": 2798.75
            }
          ]
        },
        {
          "limitType": "60%",
          "limitValues": [
            {
              "householdSize": 1,
              "incomeLimit": 71280,
              "rentLimit": 1782
            },
            {
              "householdSize": 2,
              "incomeLimit": 81420,
              "rentLimit": 2035.5
            },
            {
              "householdSize": 3,
              "incomeLimit": 91620,
              "rentLimit": 2290.5
            },
            {
              "householdSize": 4,
              "incomeLimit": 101760,
              "rentLimit": 2544
            },
            {
              "householdSize": 5,
              "incomeLimit": 109920,
              "rentLimit": 2748
            },
            {
              "householdSize": 6,
              "incomeLimit": 118080,
              "rentLimit": 2952
            },
            {
              "householdSize": 7,
              "incomeLimit": 126240,
              "rentLimit": 3156
            },
            {
              "householdSize": 8,
              "incomeLimit": 134340,
              "rentLimit": 3358.5
            }
          ]
        },
        {
          "limitType": "80%",
          "limitValues": [
            {
              "householdSize": 1,
              "incomeLimit": 95040,
              "rentLimit": 2376
            },
            {
              "householdSize": 2,
              "incomeLimit": 108560,
              "rentLimit": 2714
            },
            {
              "householdSize": 3,
              "incomeLimit": 122160,
              "rentLimit": 3054
            },
            {
              "householdSize": 4,
              "incomeLimit": 135680,
              "rentLimit": 3392
            },
            {
              "householdSize": 5,
              "incomeLimit": 146560,
              "rentLimit": 3664
            },
            {
              "householdSize": 6,
              "incomeLimit": 157440,
              "rentLimit": 3936
            },
            {
              "householdSize": 7,
              "incomeLimit": 168320,
              "rentLimit": 4208
            },
            {
              "householdSize": 8,
              "incomeLimit": 179120,
              "rentLimit": 4478
            }
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        }
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Rent Limits by Area and Bedroom Size

Returns area-grouped rent limits by bedroom size.

GET /data/derived/il/target-ami-max-rent/byarea/bybedroomsize

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`limittype`	Yes	`50%`	Baseline published limit type from the selected source data set. Limit types are source-defined and may represent AMI bands, program income limits, median-income guideline values, or other published income-limit categories.
`targetamis`	Yes	`50,60,80`	Comma-separated target percentages to calculate from the selected baseline limit type. For HUD-style data sets, these commonly correspond to AMI percentages. For other source data sets, they represent calculated percentages of the source-defined published limit.
`roundingmode`	No	`round`	Final two-decimal handling for calculated values. Supported values are `round` (default normal rounding), `truncate` (conservative truncation), and `trunc` (accepted shorthand for `truncate`).
`expenselimit`	No	`30%`	Affordability or expense percentage used in rent calculation.
`bedroomsize`	No	`2`	Filter to a bedroom size.
`bedroomsizefactor`	No	`1.5`	Factor used to derive household size from bedroom size.
`roundhouseholdsize`	No	`true`	Controls household-size rounding behavior where supported.
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear / effectivedate`	No	`2026 / 2026-05-01`	Identify the released data set. `fiscalyear` matches an exact fiscal year; `effectivedate` resolves to the data set whose effective-date range contains the supplied date.
`statecode / stateabbr`	No	`36 / NY`	State filters.
`countycode / countyname`	No	`119 / Westchester`	County filters.
`subcountyname`	No	`All`	Subcounty filter.
`areaid / areaname`	No	`METRO48325M48325 / Westchester County`	Income-limit area filters.
`page / limit`	No	`1 / 1`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/derived/il/target-ami-max-rent/byarea/bybedroomsize?datasource=HUD&datasettype=Section8&fiscalyear=2026&stateabbr=NY&countyname=Westchester&limittype=50%&targetamis=50,60,80&expenselimit=30%&bedroomsizefactor=1.5&limit=1

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`stateabbr`	`NY`
`countyname`	`Westchester`
`limittype`	`50%`
`targetamis`	`50,60,80`
`expenselimit`	`30%`
`bedroomsizefactor`	`1.5`
`limit`	`1`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "stateabbr": "NY",
    "countyname": "Westchester",
    "limittype": "50%",
    "targetamis": "50,60,80",
    "expenselimit": "30%",
    "bedroomsizefactor": 1.5,
    "limit": 1,
    "page": 1
  },
  "metadata": {
    "resource": "derived-il-ami-max-rent-groupby-area",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 1
  },
  "data": [
    {
      "id": "METRO48325M48325",
      "mfi": 164200,
      "name": "Westchester County, NY Statutory Exception Area",
      "counties": [
        {
          "stateAbbr": "NY",
          "stateCode": "36",
          "subCounty": [
            "All"
          ],
          "countyCode": "119",
          "countyName": "Westchester County"
        }
      ],
      "incomeLimits": [
        {
          "limitType": "50%",
          "limitValues": [
            {
              "incomeLimit": 59400,
              "householdSize": 1
            },
            {
              "incomeLimit": 67850,
              "householdSize": 2
            },
            {
              "incomeLimit": 76350,
              "householdSize": 3
            },
            {
              "incomeLimit": 84800,
              "householdSize": 4
            },
            {
              "incomeLimit": 91600,
              "householdSize": 5
            },
            {
              "incomeLimit": 98400,
              "householdSize": 6
            },
            {
              "incomeLimit": 105200,
              "householdSize": 7
            },
            {
              "incomeLimit": 111950,
              "householdSize": 8
            }
          ]
        }
      ],
      "derivedLimits": [
        {
          "limitType": "50%",
          "limitValues": [
            {
              "bedroomSize": 0,
              "householdSize": 1,
              "incomeLimit": 59400,
              "rentLimit": 1485
            },
            {
              "bedroomSize": 1,
              "householdSize": 1.5,
              "incomeLimit": 63625,
              "rentLimit": 1590.62
            },
            {
              "bedroomSize": 2,
              "householdSize": 3,
              "incomeLimit": 76350,
              "rentLimit": 1908.75
            },
            {
              "bedroomSize": 3,
              "householdSize": 4.5,
              "incomeLimit": 88200,
              "rentLimit": 2205
            },
            {
              "bedroomSize": 4,
              "householdSize": 6,
              "incomeLimit": 98400,
              "rentLimit": 2460
            }
          ]
        },
        {
          "limitType": "60%",
          "limitValues": [
            {
              "bedroomSize": 0,
              "householdSize": 1,
              "incomeLimit": 71280,
              "rentLimit": 1782
            },
            {
              "bedroomSize": 1,
              "householdSize": 1.5,
              "incomeLimit": 76350,
              "rentLimit": 1908.75
            },
            {
              "bedroomSize": 2,
              "householdSize": 3,
              "incomeLimit": 91620,
              "rentLimit": 2290.5
            },
            {
              "bedroomSize": 3,
              "householdSize": 4.5,
              "incomeLimit": 105840,
              "rentLimit": 2646
            },
            {
              "bedroomSize": 4,
              "householdSize": 6,
              "incomeLimit": 118080,
              "rentLimit": 2952
            }
          ]
        },
        {
          "limitType": "80%",
          "limitValues": [
            {
              "bedroomSize": 0,
              "householdSize": 1,
              "incomeLimit": 95040,
              "rentLimit": 2376
            },
            {
              "bedroomSize": 1,
              "householdSize": 1.5,
              "incomeLimit": 101800,
              "rentLimit": 2545
            },
            {
              "bedroomSize": 2,
              "householdSize": 3,
              "incomeLimit": 122160,
              "rentLimit": 3054
            },
            {
              "bedroomSize": 3,
              "householdSize": 4.5,
              "incomeLimit": 141120,
              "rentLimit": 3528
            },
            {
              "bedroomSize": 4,
              "householdSize": 6,
              "incomeLimit": 157440,
              "rentLimit": 3936
            }
          ]
        }
      ]
    }
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}

State-Level Rent Limits

Returns state-level rent limits by household size where available.

GET /data/derived/il/target-ami-max-rent/state-limits

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`limittype`	Yes	`50%`	Baseline published limit type from the selected source data set. Limit types are source-defined and may represent AMI bands, program income limits, median-income guideline values, or other published income-limit categories.
`targetamis`	Yes	`50,60,80`	Comma-separated target percentages to calculate from the selected baseline limit type. For HUD-style data sets, these commonly correspond to AMI percentages. For other source data sets, they represent calculated percentages of the source-defined published limit.
`roundingmode`	No	`round`	Final two-decimal handling for calculated values. Supported values are `round` (default normal rounding), `truncate` (conservative truncation), and `trunc` (accepted shorthand for `truncate`).
`expenselimit`	No	`30%`	Affordability or expense percentage used in rent calculation.
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear / effectivedate`	No	`2026 / 2026-05-01`	Identify the released data set. `fiscalyear` matches an exact fiscal year; `effectivedate` resolves to the data set whose effective-date range contains the supplied date.
`statecode / stateabbr`	No	`36 / NY`	State filters.
`householdsize`	No	`4`	Filter returned values to a household size.
`page / limit`	No	`1 / 1`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/derived/il/target-ami-max-rent/state-limits?datasource=HUD&datasettype=Section8&fiscalyear=2026&stateabbr=NY&limittype=50%&targetamis=50,60,80&expenselimit=30%&limit=1

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`stateabbr`	`NY`
`limittype`	`50%`
`targetamis`	`50,60,80`
`expenselimit`	`30%`
`limit`	`1`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "stateabbr": "NY",
    "limittype": "50%",
    "targetamis": "50,60,80",
    "expenselimit": "30%",
    "limit": 1,
    "page": 1
  },
  "metadata": {
    "resource": "derived-il-ami-max-rent-state-limits",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 1
  },
  "data": [
    {
      "mfi": 111900,
      "stateAbbr": "NY",
      "stateCode": "36",
      "stateName": "New York",
      "incomeLimits": [
        {
          "limitType": "50%",
          "limitValues": [
            {
              "incomeLimit": 39200,
              "householdSize": 1
            },
            {
              "incomeLimit": 44800,
              "householdSize": 2
            },
            {
              "incomeLimit": 50400,
              "householdSize": 3
            },
            {
              "incomeLimit": 55950,
              "householdSize": 4
            },
            {
              "incomeLimit": 60450,
              "householdSize": 5
            },
            {
              "incomeLimit": 64950,
              "householdSize": 6
            },
            {
              "incomeLimit": 69400,
              "householdSize": 7
            },
            {
              "incomeLimit": 73900,
              "householdSize": 8
            }
          ]
        }
      ],
      "derivedLimits": [
        {
          "limitType": "50%",
          "limitValues": [
            {
              "householdSize": 1,
              "incomeLimit": 39200,
              "rentLimit": 980
            },
            {
              "householdSize": 2,
              "incomeLimit": 44800,
              "rentLimit": 1120
            },
            {
              "householdSize": 3,
              "incomeLimit": 50400,
              "rentLimit": 1260
            },
            {
              "householdSize": 4,
              "incomeLimit": 55950,
              "rentLimit": 1398.75
            },
            {
              "householdSize": 5,
              "incomeLimit": 60450,
              "rentLimit": 1511.25
            },
            {
              "householdSize": 6,
              "incomeLimit": 64950,
              "rentLimit": 1623.75
            },
            {
              "householdSize": 7,
              "incomeLimit": 69400,
              "rentLimit": 1735
            },
            {
              "householdSize": 8,
              "incomeLimit": 73900,
              "rentLimit": 1847.5
            }
          ]
        },
        {
          "limitType": "60%",
          "limitValues": [
            {
              "householdSize": 1,
              "incomeLimit": 47040,
              "rentLimit": 1176
            },
            {
              "householdSize": 2,
              "incomeLimit": 53760,
              "rentLimit": 1344
            },
            {
              "householdSize": 3,
              "incomeLimit": 60480,
              "rentLimit": 1512
            },
            {
              "householdSize": 4,
              "incomeLimit": 67140,
              "rentLimit": 1678.5
            },
            {
              "householdSize": 5,
              "incomeLimit": 72540,
              "rentLimit": 1813.5
            },
            {
              "householdSize": 6,
              "incomeLimit": 77940,
              "rentLimit": 1948.5
            },
            {
              "householdSize": 7,
              "incomeLimit": 83280,
              "rentLimit": 2082
            },
            {
              "householdSize": 8,
              "incomeLimit": 88680,
              "rentLimit": 2217
            }
          ]
        },
        {
          "limitType": "80%",
          "limitValues": [
            {
              "householdSize": 1,
              "incomeLimit": 62720,
              "rentLimit": 1568
            },
            {
              "householdSize": 2,
              "incomeLimit": 71680,
              "rentLimit": 1792
            },
            {
              "householdSize": 3,
              "incomeLimit": 80640,
              "rentLimit": 2016
            },
            {
              "householdSize": 4,
              "incomeLimit": 89520,
              "rentLimit": 2238
            },
            {
              "householdSize": 5,
              "incomeLimit": 96720,
              "rentLimit": 2418
            },
            {
              "householdSize": 6,
              "incomeLimit": 103920,
              "rentLimit": 2598
            },
            {
              "householdSize": 7,
              "incomeLimit": 111040,
              "rentLimit": 2776
            },
            {
              "householdSize": 8,
              "incomeLimit": 118240,
              "rentLimit": 2956
            }
          ]
        }
      ]
    }
  ],
  "pagination": {
    "totalRecords": 1,
    "totalPages": 1,
    "currentPage": 1,
    "recordsPerPage": 1,
    "nextPage": null,
    "prevPage": null
  },
  "xRateLimit": {
    "period": "202606",
    "limit": null,
    "remaining": null,
    "reset": "2026-07-01T00:00:00.000Z",
    "unlimited": true
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}

State-Level Rent Limits by Bedroom Size

Returns state-level rent limits by bedroom size where available.

GET /data/derived/il/target-ami-max-rent/state-limits/bybedroomsize

Parameters

Parameter	Required	Sample Value	Description
`datasource`	Yes	`HUD`	Canonical data source or supported alias. Use Available Data Sets to discover supported values.
`limittype`	Yes	`50%`	Baseline published limit type from the selected source data set. Limit types are source-defined and may represent AMI bands, program income limits, median-income guideline values, or other published income-limit categories.
`targetamis`	Yes	`50,60,80`	Comma-separated target percentages to calculate from the selected baseline limit type. For HUD-style data sets, these commonly correspond to AMI percentages. For other source data sets, they represent calculated percentages of the source-defined published limit.
`roundingmode`	No	`round`	Final two-decimal handling for calculated values. Supported values are `round` (default normal rounding), `truncate` (conservative truncation), and `trunc` (accepted shorthand for `truncate`).
`expenselimit`	No	`30%`	Affordability or expense percentage used in rent calculation.
`bedroomsize`	No	`2`	Filter to a bedroom size.
`bedroomsizefactor`	No	`1.5`	Factor used to derive household size from bedroom size.
`roundhouseholdsize`	No	`true`	Controls household-size rounding behavior where supported.
`datasettype`	No	`Section8`	Canonical data set type or supported alias. Required unless the source can be defaulted unambiguously.
`fiscalyear / effectivedate`	No	`2026 / 2026-05-01`	Identify the released data set. `fiscalyear` matches an exact fiscal year; `effectivedate` resolves to the data set whose effective-date range contains the supplied date.
`statecode / stateabbr`	No	`36 / NY`	State filters.
`page / limit`	No	`1 / 1`	Pagination controls.

Example Request And Response

GET

https://api.finbaseco.com/api/service/v1/data/derived/il/target-ami-max-rent/state-limits/bybedroomsize?datasource=HUD&datasettype=Section8&fiscalyear=2026&stateabbr=NY&limittype=50%&targetamis=50,60,80&expenselimit=30%&bedroomsizefactor=1.5&limit=1

Headers

`Authorization`	`Bearer YOUR_API_KEY`
`Accept`	`application/json`

Query Parameters

`datasource`	`HUD`
`datasettype`	`Section8`
`fiscalyear`	`2026`
`stateabbr`	`NY`
`limittype`	`50%`
`targetamis`	`50,60,80`
`expenselimit`	`30%`
`bedroomsizefactor`	`1.5`
`limit`	`1`

Response Body

{
  "status": "success",
  "input": {
    "datasource": "HUD",
    "datasettype": "Section8",
    "fiscalyear": "2026",
    "stateabbr": "NY",
    "limittype": "50%",
    "targetamis": "50,60,80",
    "expenselimit": "30%",
    "bedroomsizefactor": 1.5,
    "limit": 1,
    "page": 1
  },
  "metadata": {
    "resource": "derived-il-ami-max-rent-state-limits-outputby-bedroomsize",
    "filterWarnings": [],
    "inputsOverridden": [],
    "inputsIgnored": [],
    "source": {
      "dataSource": "HUD",
      "dataSetType": "Section8",
      "fiscalYear": 2026,
      "effectiveDate": "2026-05-01T00:00:00.000Z",
      "releasedDate": "2026-05-30T22:21:28.537Z",
      "sourceAgencyName": "U.S. Department of Housing and Urban Development",
      "sourceProgramName": "Section 8 Income Limits",
      "entitlementCategory": "HUD"
    },
    "dataSize": 1
  },
  "data": [
    {
      "mfi": 111900,
      "stateAbbr": "NY",
      "stateCode": "36",
      "stateName": "New York",
      "incomeLimits": [
        {
          "limitType": "50%",
          "limitValues": [
            {
              "incomeLimit": 39200,
              "householdSize": 1
            },
            {
              "incomeLimit": 44800,
              "householdSize": 2
            },
            {
              "incomeLimit": 50400,
              "householdSize": 3
            },
            {
              "incomeLimit": 55950,
              "householdSize": 4
            },
            {
              "incomeLimit": 60450,
              "householdSize": 5
            },
            {
              "incomeLimit": 64950,
              "householdSize": 6
            },
            {
              "incomeLimit": 69400,
              "householdSize": 7
            },
            {
              "incomeLimit": 73900,
              "householdSize": 8
            }
          ]
        }
      ],
      "derivedLimits": [
        {
          "limitType": "50%",
          "limitValues": [
            {
              "bedroomSize": 0,
              "householdSize": 1,
              "incomeLimit": 39200,
              "rentLimit": 980
            },
            {
              "bedroomSize": 1,
              "householdSize": 1.5,
              "incomeLimit": 42000,
              "rentLimit": 1050
            },
            {
              "bedroomSize": 2,
              "householdSize": 3,
              "incomeLimit": 50400,
              "rentLimit": 1260
            },
            {
              "bedroomSize": 3,
              "householdSize": 4.5,
              "incomeLimit": 58200,
              "rentLimit": 1455
            },
            {
              "bedroomSize": 4,
              "householdSize": 6,
              "incomeLimit": 64950,
              "rentLimit": 1623.75
            }
          ]
        },
        {
          "limitType": "60%",
          "limitValues": [
            {
              "bedroomSize": 0,
              "householdSize": 1,
              "incomeLimit": 47040,
              "rentLimit": 1176
            },
            {
              "bedroomSize": 1,
              "householdSize": 1.5,
              "incomeLimit": 50400,
              "rentLimit": 1260
            },
            {
              "bedroomSize": 2,
              "householdSize": 3,
              "incomeLimit": 60480,
              "rentLimit": 1512
            },
            {
              "bedroomSize": 3,
              "householdSize": 4.5,
              "incomeLimit": 69840,
              "rentLimit": 1746
            },
            {
              "bedroomSize": 4,
              "householdSize": 6,
              "incomeLimit": 77940,
              "rentLimit": 1948.5
            }
          ]
        },
        {
          "limitType": "80%",
          "limitValues": [
            {
              "bedroomSize": 0,
              "householdSize": 1,
              "incomeLimit": 62720,
              "rentLimit": 1568
            },
            {
              "bedroomSize": 1,
              "householdSize": 1.5,
              "incomeLimit": 67200,
              "rentLimit": 1680
            },
            {
              "bedroomSize": 2,
              "householdSize": 3,
              "incomeLimit": 80640,
              "rentLimit": 2016
            },
            {
              "bedroomSize": 3,
              "householdSize": 4.5,
              "incomeLimit": 93120,
              "rentLimit": 2328
            },
            {
              "bedroomSize": 4,
              "householdSize": 6,
              "incomeLimit": 103920,
              "rentLimit": 2598
            }
          ]
        }
      ]
    }
  ],
  "pagination": {
    "totalRecords": 1,
    "totalPages": 1,
    "currentPage": 1,
    "recordsPerPage": 1,
    "nextPage": null,
    "prevPage": null
  },
  "xRateLimit": {
    "period": "202606",
    "limit": null,
    "remaining": null,
    "reset": "2026-07-01T00:00:00.000Z",
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}

Errors and Status Codes

Failed requests return a JSON error response. Authentication, entitlement, validation, and maintenance failures are surfaced as structured API responses where possible.

Status	Meaning
`400`	Invalid request, unsupported filters, or request not allowed by account limits.
`401`	Missing, invalid, inactive, or expired API key.
`403`	API key or subscription does not permit the requested resource.
`429`	Rate limit or usage limit reached.
`503`	Service maintenance or temporary unavailability.

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Responses may include xRateLimit metadata showing the relevant usage period, reset time, and plan-specific usage context when applicable.

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Customers with restricted server trust stores may need to trust or import the public certificate chain used by the production API hostname. Enterprise onboarding should validate the public certificate chain presented by api.finbaseco.com.

Support

For account, billing, API key, authentication, documented endpoint behavior, API response diagnosis, outage, or suspected data issue support, use the Finbase support portal when available.

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