RBI Treasury Bill Yield Formulas (2026)
Treasury Bills (T-Bills) are sovereign, zero-default short-term debt instruments issued by the Government of India via RBI auctions. Offered in 91-day, 182-day, and 364-day tenures, T-Bills are issued at a discount and redeemed at full face value upon maturity.
Because T-Bills carry zero credit risk and offer high liquidity, corporate treasuries and conservative individuals use them as cash management tools. Compare T-Bill yields against bank fixed deposits on our fixed deposit calculator and calculate post-tax earnings with our post-tax FD calculator. Remember that T-Bill appreciation is taxed as short-term capital gains at your slab rate—compute your net tax on our income tax calculator, evaluate short-term lending returns on our simple interest calculator, park your liquid cash safely with our emergency fund calculator, and evaluate debt capacity on our debt-to-income calculator.
| T-Bill Tenure | Auction Frequency | YTM Formula |
|---|---|---|
| 91-Day T-Bill | Weekly (Every Wednesday) | [(100 - Price) / Price] * (365 / 91) * 100 |
| 182-Day T-Bill | Bi-Weekly | [(100 - Price) / Price] * (365 / 182) * 100 |
| 364-Day T-Bill | Bi-Weekly | [(100 - Price) / Price] * (365 / 364) * 100 |
RBI Treasury Bill (T-Bill) Mechanics & Tenures
- Zero-Coupon Discount Bonds: T-Bills pay no periodic interest coupons. Issued at a discount to Par (₹100) and redeemed at full ₹100 Face Value at maturity.
- 3 Tenures: 91-Day T-Bills (weekly auction), 182-Day T-Bills, and 364-Day T-Bills (bi-weekly auctions).
Annualized YTM Formula & Tax Treatment
- YTM Formula: Annualized Yield % = [(100 - Cutoff Price) / Cutoff Price] * (365 / Tenure Days) * 100.
- Zero TDS & STCG Tax: Zero TDS deducted at source. Returns are taxed as Short-Term Capital Gains (STCG) at your income tax slab rate.
- Retail Direct Buying: Retail investors can buy T-Bills directly via RBI Retail Direct Portal or Zerodha/Groww apps.
Sovereign Safety Advantage
Treasury Bills offer 100% sovereign credit backing from the Government of India, making them safer than bank FDs for parking short-term surplus funds.