US Treasury Fiscal Data API Reference

Overview

The US Treasury's Fiscal Data API provides machine-readable access to federal financial data: national debt, treasury securities, interest rates, yield curves, revenue, spending, and more. Maintained by the Bureau of the Fiscal Service.

Base URL

https://api.fiscaldata.treasury.gov/services/api/fiscal_service

Authentication

No API key required. The API is fully open and public.

Rate Limits

• No formal rate limits published.
• Reasonable use expected; no authentication or throttling documented.
• For bulk data, use pagination with large page sizes.

Key Endpoints

URL Pattern

All dataset endpoints follow:

GET /services/api/fiscal_service/{endpoint}?{parameters}

Common Query Parameters (apply to all endpoints)

Filter Operators: eq (equals), lt, lte, gt, gte, in (comma-separated values)

1. Treasury Yield Curve Rates (Daily)

GET /v2/accounting/od/avg_interest_rates

Better endpoint for yield curves:

GET /v1/accounting/od/rates_of_exchange

Daily Treasury Par Yield Curve Rates: Note: Daily yield curve rates are published at https://home.treasury.gov/resource-center/data-chart-center/interest-rates/ and available via the TreasuryDirect API. For programmatic access via Fiscal Data:

GET /v2/accounting/od/avg_interest_rates

Example -- Average interest rates on Treasury securities:

https://api.fiscaldata.treasury.gov/services/api/fiscal_service/v2/accounting/od/avg_interest_rates?filter=record_date:gte:2024-01-01&sort=-record_date&page[size]=100

Response:

{
  "data": [
    {
      "record_date": "2024-10-31",
      "security_type_desc": "Treasury Bills",
      "security_desc": "Treasury Bills",
      "avg_interest_rate_amt": "5.223",
      "src_line_nbr": "1",
      "record_fiscal_year": "2025",
      "record_fiscal_quarter": "1",
      "record_calendar_year": "2024",
      "record_calendar_quarter": "4",
      "record_calendar_month": "10",
      "record_calendar_day": "31"
    }
  ],
  "meta": {
    "count": 100,
    "labels": { ... },
    "dataTypes": { ... },
    "dataFormats": { ... },
    "total-count": 1234,
    "total-pages": 13
  },
  "links": {
    "self": "&page%5Bnumber%5D=1&page%5Bsize%5D=100",
    "first": "&page%5Bnumber%5D=1&page%5Bsize%5D=100",
    "prev": null,
    "next": "&page%5Bnumber%5D=2&page%5Bsize%5D=100",
    "last": "&page%5Bnumber%5D=13&page%5Bsize%5D=100"
  }
}

2. Debt to the Penny (Daily National Debt)

GET /v2/accounting/od/debt_to_penny

Example -- Debt since 2024:

https://api.fiscaldata.treasury.gov/services/api/fiscal_service/v2/accounting/od/debt_to_penny?filter=record_date:gte:2024-01-01&sort=-record_date&page[size]=10

Key Fields: record_date, tot_pub_debt_out_amt, intragov_hold_amt, debt_held_public_amt

3. Treasury Securities Auctions

GET /v1/accounting/od/auctions_query

Example -- Recent T-Bill auctions:

https://api.fiscaldata.treasury.gov/services/api/fiscal_service/v1/accounting/od/auctions_query?filter=security_type:eq:Bill&sort=-auction_date&page[size]=10

Key Fields: cusip, security_type, security_term, auction_date, issue_date, maturity_date, high_yield, high_discount_rate, bid_to_cover_ratio, total_accepted

4. Monthly Treasury Statement (Revenue & Outlays)

GET /v1/accounting/mts/mts_table_5

Example -- Federal receipts/outlays:

https://api.fiscaldata.treasury.gov/services/api/fiscal_service/v1/accounting/mts/mts_table_5?filter=record_date:gte:2024-01-01&sort=-record_date&page[size]=50

5. Federal Spending by Category

GET /v1/accounting/mts/mts_table_9

Example:

https://api.fiscaldata.treasury.gov/services/api/fiscal_service/v1/accounting/mts/mts_table_9?filter=record_date:gte:2024-01-01&sort=-record_date

6. Treasury Reporting Rates of Exchange

GET /v1/accounting/od/rates_of_exchange

Example -- Exchange rates for a quarter:

https://api.fiscaldata.treasury.gov/services/api/fiscal_service/v1/accounting/od/rates_of_exchange?filter=record_date:eq:2024-09-30&page[size]=200

Key Fields: country_currency_desc, exchange_rate, record_date, effective_date

7. Interest Expense on the Debt

GET /v2/accounting/od/interest_expense

Example:

https://api.fiscaldata.treasury.gov/services/api/fiscal_service/v2/accounting/od/interest_expense?filter=record_fiscal_year:eq:2024&sort=-record_date

8. Savings Bonds Rates

GET /v2/accounting/od/sb_value

Common Endpoint Paths

Response Format

All JSON responses share the same envelope:

• data: Array of result objects
• meta: Contains count, total-count, total-pages, field labels and data types
• links: Pagination links (self, first, prev, next, last)

Notes

• All monetary amounts are returned as strings to preserve precision.
• Dates use YYYY-MM-DD format in the record_date field.
• The filter parameter supports chaining: filter=field1:eq:val1,field2:gte:val2.
• Use fields= to reduce response size by requesting only needed columns.
• The API documentation and dataset explorer is at: https://fiscaldata.treasury.gov/api-documentation/
• For Treasury yield curve rates specifically, FRED series DGS1, DGS2, DGS5, DGS10, DGS30 may be more convenient.