TBILLPRICE Function in Google Sheets: Formula, Examples & Troubleshooting

=TBILLPRICE(settlement, maturity, discount)

All three arguments are required. settlement is the delivery/purchase settlement date, maturity is the redemption date, and discount is the bill’s discount rate. Enter 4% as 4% or 0.04, not 4.

Google limits maturity to one year or less after settlement and instructs users to supply a positive discount percentage in the zero-to-one range. Dates should be genuine date values. There is no argument for a different day-count basis or redemption amount. Google TBILLPRICE reference.

The endpoint behavior at exactly zero or exactly one is not established here. Use an ordinary positive rate below one for these examples.

1. In B7 enter =TBILLPRICE(B2,B3,B4).
2. Expect 99 as the modeled per-100 price.
3. In B8 enter =B3-B2, displayed as a number. Expect 90 actual days.
4. Check B7 with =100*(1-B4*B8/360). Its independent result is also 99.
5. In B9 enter =B5*B7/100. The modeled purchase amount is 9,900.
6. In B10 enter =B5-B9. The difference between face amount and modeled purchase amount is 100.

B5 is your position-sizing input; it is not passed to TBILLPRICE. Passing 10,000 as the third argument would supply an invalid discount rate, not a face amount.

Google’s published sheet uses February 1 to June 30, 2011, a 149-day interval, with a 2.5% discount rate. It displays 98.96527778 for TBILLPRICE. The arithmetic 100*(1-0.025*149/360) reproduces that displayed result. This supports the per-100, actual-day, 360-denominator audit used here. It is documentation evidence, not a newly executed test. Published Google example.

Google also describes TBILLPRICE as the Treasury-bill-convention counterpart of PRICEDISC. That does not create a fourth optional basis argument: the documented TBILLPRICE syntax still has exactly three inputs.

Keep the 90-day interval and 10,000 face amount fixed. Put 3%, 4%, and 5% in D2:D4. In E2 enter =TBILLPRICE($B$2,$B$3,D2) and fill down. In F2 enter =$B$5*E2/100 and fill down.

The price decreases as the discount increases. This is a scenario comparison, not a recommendation or a current market quote.

A discount rate uses face value as its reference amount. The 90-day holding-period gain on the 9,900 paid is =100/9900, approximately 1.010101%, rather than exactly 1%. Keep that difference visible when comparing a discount quote with a return on money invested.

Google’s published error sheet shows #NUM! for three concrete cases: March 31, 2008 to June 1, 2009 at 9%; March 31, 2009 to June 1, 2008 at 9%; and March 31, 2008 to March 1, 2009 at −5%. These respectively illustrate an overlong term, reversed chronology, and a negative discount with otherwise forward dates. Published error examples.

Use DATE rather than typing a slash-separated date directly into a formula. Check dates before wrapping the result in IFERROR; replacing all errors with zero could make an invalid row resemble a free purchase. The exact interpretation of the one-year boundary across leap years is not established by these examples, so boundary cases require separate verification.

This guide covers the currently documented Google Sheets function and ordinary short-term inputs. No introduction version, retirement date, or earliest functioning version was established. The examples do not establish Excel or another engine’s behavior. TBILLPRICE returns a price from a discount rate; TBILLYIELD starts from a price. Do not swap their third arguments.

Related: DATE, ISNUMBER, and ROUND.

References checked October 17, 2026: Google TBILLPRICE documentation and its published result and inputs.