Treasury Bill (T-Bill) Yield Calculator
Calculate US Treasury Bill purchase price, annualized discount yield, bank discount rate, and money market investment yield on short-term government paper.
Enter Parameters
Adjust inputs to calculate real-time estimates
What this treasury bill (t-bill) yield calculator is showing you
This Treasury Bill (T-Bill) Yield Calculator is designed to provide clear, reliable financial mathematics to assist in personal money management and scenario planning.
The tool focuses on transparent formulas, actionable outputs, and practical planning insights to support informed financial decision-making.
Mathematical Model
Discount Yield = (Discount/Par)*(360/Days)*100; BEY = (Discount/Price)*(365/Days)*100; APY = ((1+Discount/Price)^(365/Days) - 1)*100
Inputs that matter most
Understanding how each variable impacts the final calculation
T-Bill Face Value (Par)
The primary value establishes the baseline magnitude for the entire calculation model.
Auction Purchase Price
The rate or percentage factor determines how the baseline value expands, discounts, or incurs expense over the modeled period.
Days to Maturity
The timeframe or secondary parameter provides essential context, defining the duration or conditions under which the math operates.
How to interpret your results
Use the calculation output as an objective decision-making checkpoint. Test multiple input scenarios to observe which variables exert the strongest influence on the final result.
Complement numerical outputs with comprehensive financial planning principles before executing binding commitments.
- ✓ Test both conservative and optimistic scenarios to understand the full sensitivity range of your financial plan.
- ✓ Verify critical calculations against official institutional documentation and qualified professional counsel.
Worked Example Scenario
The snapshot below illustrates a representative calculation using the standard initial parameters:
Bond Equivalent Yield (BEY)
5.14%
Effective Annual APY
5.21%
Bank discount yield (360-day)
4.95%
Dollar discount profit
₹ 250.00
T-Bills are sold at a discount to par. The Bond Equivalent Yield converts the 360-day money market discount into a standard 365-day annualized return.
General Financial Calculation Considerations
This calculator provides educational estimates designed for preliminary planning and scenario analysis. Financial outcomes in practice are influenced by individual contractual terms, institutional fees, tax obligations, and market changes.
Verify all critical financial calculations with licensed advisers, institutional documentation, and qualified legal or tax professionals before executing binding agreements.
Key Factors to Review:
- • Calculations are mathematical models based on user-supplied variables.
- • Real-world results may vary due to fees, taxes, and contractual specifics.
Frequently Asked Questions
Why are T-Bills exempt from state and local income tax? ▼
Under US federal law, interest on US Treasury securities (T-Bills, Notes, Bonds) is exempt from all state and local income taxes.
Why is BEY higher than discount rate? ▼
The discount rate divides discount by par on a 360-day year, while BEY divides discount by actual cash paid on a 365-day year, yielding a truer return.