TBILLYIELD Function in Microsoft Excel: Syntax, Examples & Troubleshooting

=TBILLYIELD(settlement, maturity, pr)

All three arguments are required. Settlement and maturity identify the bill’s interval. pr is its price per 100 face value, so a price of 98 is entered as 98, not 0.98. The result is a rate, which can be displayed using Percentage format.

Both date arguments should be real Excel dates or DATE formulas. Microsoft documents truncating settlement and maturity to integers, so a time component does not create a fractional trading day. There is no basis argument in this function; do not append one copied from a different security function.

For the examples, enter =DATE(2026,1,15) in B2 and =DATE(2026,4,15) in B3. The ordinary date difference is 90 days. This short, fixed interval makes the example independently reproducible without a changing current-date input.

1. Enter 98 in B4.
2. Enter =TBILLYIELD(B2,B3,B4) in D2.
3. Expected result: approximately 0.08163265306, or 8.163265306%.

The independently checked equation is (100-98)/98*360/90. The gain of 2 is about 2.040816327% of the price paid over the quarter. Annualizing multiplies that by four.

=TBILLYIELD(DATE(2026,1,15),DATE(2026,2,14),99.5)

Expected result: approximately 0.06030150754, or 6.030150754%. There are 30 actual days and the gain is 0.5 per 99.5 invested. The independent check is 0.5/99.5*360/30.

The fact that the bill’s price can be produced by a 6% discount quotation does not make its price-based yield exactly 6%. The gain’s denominator is different.

For the original 90-day price of 98, the holding-period return is 2/98, approximately 2.040816327%. TBILLYIELD annualizes it on a 360-day factor to 8.163265306%. A simple 365-day annualization of the same price return would be 8.276643991%. A redemption-based discount quotation is 2/100×360/90 = 8%.

All these numbers can describe the same price difference, but they answer different quotation questions. Keep the denominator and annual basis in the column heading when comparing rates. Do not choose a function merely because it produces the largest percentage.

A face-value scaling check is also useful: face 25000 costs 24500 at price 98 and produces gain 500. 500/24500*360/90 returns the same TBILLYIELD figure. Scaling both cash amounts leaves the ratio unchanged.

Microsoft documents #VALUE! for invalid date inputs. #NUM! occurs if price is zero or negative, settlement is greater than or equal to maturity, or maturity is more than one year after settlement. Use a positive term and a positive price.

Do not add a day-count basis argument: none exists. Date fractions are truncated, and the examples intentionally use whole calendar dates. The reference describes the maturity limit as one calendar year; the 360 in the yield equation is an annualization factor, not a blanket 360-day date cutoff.

The function does not model reinvestment, fees, taxes or intermediate cash flows. It is a formula for the specified quotation convention rather than a complete net-return forecast or investment recommendation.

Microsoft’s reference checked on October 17, 2026 lists: Excel for Microsoft 365 Excel for Microsoft 365 for Mac Excel 2024 Excel 2024 for Mac Excel 2021 Excel 2021 for Mac Excel 2019 Excel 2016. This current support list does not establish the first release. The introduction version and last functioning version have not been established from the reviewed documentation. No retirement is asserted.

Example verification: Expected numerical results are independently calculated; text and shape expectations follow the documented contract. These examples have not been tested in Microsoft Excel. No screenshot or native execution is claimed.

DATE in Excel | DAYS in Excel | ROUND in Excel

• Microsoft TBILLYIELD reference, retrieved October 17, 2026.