Is this Treasury API really free?

Yes, this API is 100% free with no restrictions. There are no hidden costs, no premium tiers, no API keys required, and no rate limits. The infrastructure is built to handle millions of requests per month at no charge.

Do I need an API key or authentication?

No authentication is required. You can start making HTTP requests immediately without any sign-ups, API keys, or OAuth flows.

Can this API handle high traffic?

Yes, the infrastructure is optimized to serve millions of API calls per month. It features intelligent caching, database optimizations, redundant systems, and enterprise-grade cloud infrastructure with 99.9%+ uptime.

How often is the data updated?

Data is automatically fetched and updated from official US Treasury sources every business day.

US Treasury Par Yield Curve Rates API

Q: What are US Treasury Par Yield Curve Rates?

US Treasury Par Yield Curve Rates represent the interest rates (yields) for US Treasury securities across different maturity periods, from 1 month to 30 years. These rates are derived from the closing market bid prices of actively traded Treasury securities and are published daily by the US Department of the Treasury.

100% Free, unlimited access to daily US Treasury yield curve data. No API keys, no rate limits, no credit card required.

Built to scale: Optimized infrastructure handling millions of requests monthly with 99.9% uptime.

Check out our US Treasury Yield Curve Viewer

Treasury Interest Rates API Documentation

Overview

This API provides access to US Treasury daily yield curve rates. The data is fetched from the US Treasury Department and includes interest rates for various maturities ranging from 1 month to 30 years.

Endpoint

GET https://moneymatter.me/api/treasury/interest-rates

Query Parameters

year (optional): Filter results by a specific year (e.g., 2025).
Example: https://moneymatter.me/api/treasury/interest-rates?year=2025
date (optional): Filter results by a specific date in YYYY-MM-DD format.
Example: https://moneymatter.me/api/treasury/interest-rates?date=2025-01-02
lastDailyResult (optional): When set to true, returns only the most recent daily result.
Example: https://moneymatter.me/api/treasury/interest-rates?lastDailyResult=true

Response Format

{
  "success": true,
  "data": [
    {
      "NEW_DATE": "2025-01-02T00:00:00.000Z",
      "BC_1MONTH": 4.45,
      "BC_1_5MONTH": 4.40,
      "BC_2MONTH": 4.36,
      "BC_3MONTH": 4.36,
      "BC_6MONTH": 4.25,
      "BC_1YEAR": 4.17,
      "BC_2YEAR": 4.25,
      "BC_3YEAR": 4.29,
      "BC_5YEAR": 4.38,
      "BC_7YEAR": 4.47,
      "BC_10YEAR": 4.57,
      "BC_20YEAR": 4.86,
      "BC_30YEAR": 4.79,
      "BC_30YEARDISPLAY": 4.79
    }
  ],
  "count": 1,
  "fetchedAt": "2025-10-26T12:00:00.000Z",
  "source": "https://home.treasury.gov/..."
}

Response Fields

success (boolean): Indicates whether the API request was successful.
data (array): Array of treasury rate objects. Each object represents daily yield curve rates.
count (number): Number of records returned in the data array.
fetchedAt (string): ISO 8601 timestamp indicating when the data was fetched from the API.
source (string): URL of the US Treasury Department source for the data.

Data Object Fields

Each object in the data array contains the following fields:

NEW_DATE (string): The date for which the treasury rates are reported, in ISO 8601 format.
BC_1MONTH (number | null): 1-month treasury bill par yield rate (percentage). May be null if data is unavailable.
BC_1_5MONTH (number | null): 1.5-month treasury bill par yield rate (percentage). May be null if data is unavailable.
BC_2MONTH (number | null): 2-month treasury bill par yield rate (percentage). May be null if data is unavailable.
BC_3MONTH (number | null): 3-month treasury bill par yield rate (percentage). May be null if data is unavailable.
BC_6MONTH (number | null): 6-month treasury bill par yield rate (percentage). May be null if data is unavailable.
BC_1YEAR (number | null): 1-year treasury note par yield rate (percentage). May be null if data is unavailable.
BC_2YEAR (number | null): 2-year treasury note par yield rate (percentage). May be null if data is unavailable.
BC_3YEAR (number | null): 3-year treasury note par yield rate (percentage). May be null if data is unavailable.
BC_5YEAR (number | null): 5-year treasury note par yield rate (percentage). May be null if data is unavailable.
BC_7YEAR (number | null): 7-year treasury note par yield rate (percentage). May be null if data is unavailable.
BC_10YEAR (number | null): 10-year treasury note par yield rate (percentage). May be null if data is unavailable.
BC_20YEAR (number | null): 20-year treasury bond par yield rate (percentage). May be null if data is unavailable.
BC_30YEAR (number | null): 30-year treasury bond par yield rate (percentage). May be null if data is unavailable.
BC_30YEARDISPLAY (number | null): 30-year treasury bond par yield rate for display purposes (percentage). May be null if data is unavailable.

Note: All rate values are expressed as percentages (e.g., 4.45 means 4.45%). Any field may be null if the US Treasury did not publish data for that maturity on the given date.

Example Usage

Get data for current year (default): https://moneymatter.me/api/treasury/interest-rates
Get data for specific year: https://moneymatter.me/api/treasury/interest-rates?year=2024
Get data for specific date: https://moneymatter.me/api/treasury/interest-rates?date=2025-01-02
Get most recent rate: https://moneymatter.me/api/treasury/interest-rates?lastDailyResult=true

Current Treasury Rates (2026)

Below are the most recent US Treasury Par Yield Curve rates. Data is sourced directly from the US Department of the Treasury and updated daily.

Treasury Yield Curve Rates - 2026

Daily interest rates for US Treasury securities across various maturities

Date	1 Month	1.5 Month	2 Month	3 Month	6 Month	1 Year	2 Year	3 Year	5 Year	7 Year	10 Year	20 Year	30 Year
2026-01-02	3.72%	3.71%	3.66%	3.65%	3.58%	3.47%	3.47%	3.55%	3.74%	3.95%	4.19%	4.81%	4.86%
2026-01-05	3.71%	3.68%	3.64%	3.64%	3.57%	3.47%	3.46%	3.53%	3.71%	3.92%	4.17%	4.79%	4.85%
2026-01-06	3.7%	3.7%	3.61%	3.63%	3.56%	3.48%	3.47%	3.54%	3.72%	3.93%	4.18%	4.8%	4.86%
2026-01-07	3.7%	3.69%	3.6%	3.62%	3.56%	3.48%	3.47%	3.53%	3.7%	3.91%	4.15%	4.76%	4.82%
2026-01-08	3.7%	3.69%	3.63%	3.62%	3.56%	3.48%	3.49%	3.56%	3.74%	3.95%	4.19%	4.79%	4.85%

Data source: US Department of the Treasury - as XML

Total entries: 5

Why This API Exists

While working on a financial analysis platform for a banking startup in New York, I encountered a common challenge: accessing US Treasury yield curve data programmatically was unnecessarily complicated. The official Treasury.gov XML feeds are cumbersome to parse, and many third-party APIs either charge premium fees or impose restrictive rate limits.

What started as an internal tool quickly proved its value, so I decided to open it to the public. Every developer, financial analyst, and researcher should have easy access to this fundamental economic data without jumping through hoops or paying excessive fees. This API is completely free to use—no charges, no API keys, no authentication, and no rate limits. It returns clean JSON data that's ready to use in your applications.

I've invested in building robust, optimized infrastructure that can comfortably handle millions of requests. Whether you're a solo developer building a side project or a company serving thousands of users, this API is built to scale with you. The infrastructure is designed for high availability with redundant systems, intelligent caching, and optimized query performance to ensure fast response times even under heavy load.

What Are Treasury Par Yield Curve Rates?

The US Treasury Par Yield Curve Rates represent the interest rates (yields) for US Treasury securities across different maturity periods, from 1 month to 30 years. These rates are derived from the closing market bid prices of actively traded Treasury securities and are published daily by the US Department of the Treasury.

A “par yield” is the coupon rate at which a Treasury security would trade at its par value (face value). In simpler terms, it's the theoretical interest rate that would make a bond worth exactly $100 today if you're going to receive $100 back at maturity plus periodic interest payments.

Why Treasury Rates Matter

Treasury yield curve rates are among the most important indicators in global finance and economics. Here's why they matter:

Benchmark for All Interest Rates: Treasury rates serve as the baseline for virtually all other interest rates in the economy, including mortgage rates, corporate bond yields, and savings account rates.
Economic Health Indicator: The shape of the yield curve provides insights into market expectations about future economic growth, inflation, and recession risks. An inverted yield curve (where short-term rates exceed long-term rates) has historically preceded recessions.
Investment Valuation: Financial professionals use Treasury rates as the “risk-free rate” in models like DCF (Discounted Cash Flow) analysis, CAPM (Capital Asset Pricing Model), and options pricing.
Portfolio Management: Investors and fund managers monitor yield curve movements to make asset allocation decisions and assess relative value across different securities.
Monetary Policy Gauge: Changes in Treasury rates reflect and influence Federal Reserve policy decisions, helping market participants anticipate future rate adjustments.

Common Use Cases

This API is designed to support a wide range of financial applications and analyses:

Building financial dashboards and analytics platforms
Creating yield curve visualizations and historical trend analysis
Implementing fixed income valuation models
Conducting economic research and academic studies
Developing automated trading algorithms and risk management systems
Calculating present values and discount rates for business valuation
Teaching finance and economics concepts with real-world data