US Treasury Bill Calculator

Calculate US Treasury Bill discount rate, investment yield, and returns. Safe, government-backed investments.

Calculate T-Bill yields and returns.

About This Calculator

Analyze risk-free investments with the Treasury Bill Calculator. T-Bills are backed by the full faith and credit of the US government, making them one of the safest investments available.

Treasury Bills are short-term government securities sold at a discount. You pay less than face value and receive the full face value at maturity—the difference is your return. With current yields around 4-5%, T-Bills are competitive with savings accounts while being state and local tax-exempt.

T-Bill Yield Formulas

Discount Rate = (Discount ÷ Face) × (360 ÷ Days)
Investment Yield = (Discount ÷ Price) × (365 ÷ Days)

Investment yield is more accurate for comparing to other investments.

Practical Example

$10,000 face value 13-week T-Bill purchased for $9,875: Discount = $125. Discount rate = 4.95%. Investment yield = 5.07%. Annual return on $9,875 = ~$506.

Current T-Bill Rates (Sample)

MaturityRate Range
4-week4.5% - 5.5%
13-week4.7% - 5.3%
26-week4.5% - 5.2%
52-week4.3% - 5.0%

Pro Tips

  • Buy through TreasuryDirect.gov with no fees
  • State/local tax-exempt—great for high-tax states
  • Use "T-Bill ladder" for liquidity and reinvestment
  • Minimum purchase is $100

Related tools: Bond Calculator for longer-term securities, Tax Equivalent Yield Calculator for tax comparisons, and Investment Calculator for portfolio planning.

Frequently Asked Questions

How is T-Bill yield calculated?

Discount Rate = (Discount ÷ Face) × (360 ÷ Days). Investment Yield = (Discount ÷ Price) × (365 ÷ Days). Investment yield is more accurate for comparisons.

Are Treasury Bills a good investment?

Yes for safety and short-term parking. Zero default risk, state/local tax-exempt, currently 4-5% yields. Best for emergency funds and short-term goals.

How to buy Treasury Bills?

Buy directly at TreasuryDirect.gov (no fees) or through brokers. Minimum $100. Auctions for 4, 8, 13, 17, 26, and 52-week terms. Auto-roll feature available.