How a Treasury bill earns money when it is sold at a discount

Key takeaways

• TreasuryDirect says bills are sold at a discount or at par and are paid at face value when they mature.
• TreasuryDirect says that for bills, interest is the difference between the price paid and the face value received at maturity rather than a semiannual coupon payment.
• TreasuryDirect's pricing page gives the bill-pricing formula and shows that the discount amount and the earned interest are the same price gap expressed through the auction terms.

A bill is a price-gap instrument, not a coupon instrument

TreasuryDirect says Treasury bills are sold at a discount or at par and that when they mature the Treasury pays face value. That is the core mechanical difference readers need before they compare bills with notes or bonds.

Unlike notes and bonds, the investor is not waiting for periodic coupon checks. The return comes from buying below face value and later receiving face value at maturity, or from buying at par and simply receiving par back.

Treasury states the return directly

TreasuryDirect says that for bills, interest is the difference between what you paid and the face value you get when the bill matures. Its pricing page repeats the same idea and even gives the bill-pricing formula to translate an auction discount rate into a purchase price.

That means the line between `discount` and `interest` is not conceptual fluff. The discount is the source of the interest when the bill matures, because the face-value repayment closes the gap.

• Do not look for a coupon stream when reading a Treasury bill.
• Focus on purchase price versus face value.
• Treat the bill's return as the maturity payment closing the discount gap.

Why this matters for rate reading

Bills are often used as clean short-term rate references, but their cash-flow structure is different from longer-term coupon-paying Treasuries. That difference matters when readers compare quoted bill yields with the actual cash mechanics of the instrument.

For Hynexly readers, the practical rule is simple: when a bill yield moves, remember that the investor experience is still governed by the discounted purchase price and the fixed face-value maturity payment, not by interim coupon income.

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