Work out treasury bill discount rate instantly with clear inputs, formula shown and shareable results.
Bills are quoted on a discount basis using a 360-day year and dividing by face value, which understates the true return. Converting to an investment yield on price with a 365-day year gives the figure comparable with deposits.
Discount to yield
Discount = F × rate × days/360; investment yield = discount/price × 365/days
Figures are estimates based on the inputs given. Bank charges, regulatory minima and market rates change and differ between institutions and jurisdictions. This is not financial advice — confirm with your bank or treasury policy.
The discount basis is a legacy auction convention; the investment yield is what investors actually earn.
The investment yield, because it divides by the smaller price and uses a 365-day year.