Treasury bill (T-bill) calculator
Turn a treasury bill discount rate into what you actually earn. Works for 91, 182 and 364-day Nigerian T-bills.
How treasury bills work in Nigeria
Nigerian treasury bills are short-term federal government securities sold at auction through the Central Bank of Nigeria. They come in three tenors: 91, 182 and 364 days. You buy at a discount to face value, and when the bill matures the government pays you the full face value.
Discount rate vs true yield
The rate announced at each auction is a discount rate, also called the stop rate. It is measured against the face value, not against the money you pay. Because you pay less than face value, your return on what you actually invest is always higher. That higher figure is the true yield.
Worked example
Say a 364-day bill clears at a 17.15% discount rate. For every ₦1,000,000 of bills (the face value), you pay about ₦828,970 today, and the government pays you the full ₦1,000,000 after 364 days.
Your gain is about ₦171,030 on ₦828,970 invested. Measured against what you actually paid, that is a true yield of about 20.7% a year, not 17.15%.
Things to check before you buy
Rates change at every auction, so use the latest results from the CBN or the Debt Management Office. Your bank, broker or investment app may charge fees, and tax treatment can change, so ask them what applies to you. If you sell before maturity, you sell in the secondary market at that day's price, which can be different from what you expected.
Common questions
What is the difference between the discount rate and the true yield?
The discount rate is measured against the face value you receive at maturity. The true yield is measured against the smaller amount you actually pay. For the same bill, the true yield is higher. For example, a 17.15% discount rate on a 364-day bill is about a 20.7% true yield.
What tenors can I buy?
Nigerian treasury bills are issued in 91-day, 182-day and 364-day tenors.
Where do I find the latest rates?
The CBN publishes treasury bill auction results, and the Debt Management Office and many brokers and investment apps also share them. Rates reset at each auction.
How do I buy treasury bills?
You usually buy through a commercial bank, a licensed stockbroker or an investment app that offers them. Ask about minimum amounts, fees and when your money is paid out.
Is my money guaranteed?
Treasury bills are issued by the federal government, and holding one to maturity pays you the face value. But selling early can give a different amount, inflation can reduce what your money can buy, and fees may apply. This calculator is an estimate, not advice.
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