USAspending.gov Budget Functions API

Federal budget functional classification reference data.

Documentation GitHub OpenAPI

Operations 2

1 of 2 operations are conformant: apis.io called them with no credentials and the responses matched this contract. Checked 2026-11-12. how this works · status file

GET /budget_functions/list_budget_functions/ List budget functions conformant #

GET /budget_functions/list_budget_subfunctions/ List budget subfunctions #

Documentation

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Documentation

https://api.usaspending.gov/docs/endpoints

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APIReference

https://github.com/fedspendingtransparency/usaspending-api/blob/master/usaspending_api/api_contracts/contracts/v2/search/spending_by_award.md

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APIReference

https://github.com/fedspendingtransparency/usaspending-api/blob/master/usaspending_api/api_contracts/contracts/v2/agency/toptier_code.md

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APIReference

https://github.com/fedspendingtransparency/usaspending-api/blob/master/usaspending_api/api_contracts/contracts/v2/recipient.md

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APIReference

https://github.com/fedspendingtransparency/usaspending-api/blob/master/usaspending_api/api_contracts/contracts/v2/federal_accounts/account_number.md

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APIReference

https://github.com/fedspendingtransparency/usaspending-api/blob/master/usaspending_api/api_contracts/contracts/v2/budget_functions/list_budget_functions.md

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APIReference

https://github.com/fedspendingtransparency/usaspending-api/blob/master/usaspending_api/api_contracts/contracts/v2/disaster/overview.md

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APIReference

https://github.com/fedspendingtransparency/usaspending-api/blob/master/usaspending_api/api_contracts/contracts/v2/bulk_download/awards.md

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APIReference

https://github.com/fedspendingtransparency/usaspending-api/blob/master/usaspending_api/api_contracts/contracts/v2/references/toptier_agencies.md

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APIReference

https://github.com/fedspendingtransparency/usaspending-api/blob/master/usaspending_api/api_contracts/contracts/v2/subawards.md

Specifications

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OpenAPI

https://artifacts.apis.io/usaspending/openapi/usaspending-budget-functions-api-openapi.yml

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OpenAPI Specification

openapi: 3.2.0
info:
  title: USAspending Budget Functions API
  description: The USAspending API provides free, public, unauthenticated access to U.S.
  version: v2
  contact:
    name: USAspending.gov / Bureau of the Fiscal Service
    url: https://www.usaspending.gov
  license:
    name: Open source (CC0 / public domain, U.S. Government work)
    url: https://github.com/fedspendingtransparency/usaspending-api/blob/master/LICENSE.md
servers:
- url: https://api.usaspending.gov/api/v2
  description: Production (no authentication required)
tags:
- name: Budget Functions
  description: Federal budget functional classification reference data.
paths:
  /budget_functions/list_budget_functions/:
    get:
      operationId: listBudgetFunctions
      tags:
      - Budget Functions
      summary: List budget functions
      description: Returns all federal budget functions, ordered by title.
      responses:
        '200':
          description: List of budget functions.
          content:
            application/json:
              schema:
                type: object
                properties:
                  results:
                    type: array
                    items:
                      $ref: '#/components/schemas/BudgetFunction'
  /budget_functions/list_budget_subfunctions/:
    get:
      operationId: listBudgetSubfunctions
      tags:
      - Budget Functions
      summary: List budget subfunctions
      description: Returns all federal budget subfunctions, optionally scoped to a parent budget function.
      parameters:
      - name: budget_function
        in: query
        required: false
        description: Budget function code to scope the subfunction list to.
        schema:
          type: string
      responses:
        '200':
          description: List of budget subfunctions.
          content:
            application/json:
              schema:
                type: object
                properties:
                  results:
                    type: array
                    items:
                      $ref: '#/components/schemas/BudgetSubfunction'
components:
  schemas:
    BudgetFunction:
      type: object
      properties:
        budget_function_code:
          type: string
        budget_function_title:
          type: string
    BudgetSubfunction:
      type: object
      properties:
        budget_subfunction_code:
          type: string
        budget_subfunction_title:
          type: string