Glossary term
Discount rate vs investment rate on T-bills
On , at the auction of the 8-week bill (a reopening), the high discount rate was 4.050% and the investment rate 4.132%.
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High discount rate at the 8-week bill auction of 15 October 2026: 4.050%, above the median of the earlier auctions shown, 3.660%
The linesLatest:
- High discount rate4.050%
- Investment rate4.132%
Each point is one 8-week bill auction; pointing at the chart shows its date and figures.
The linesLatest:
- High discount rate4.050%
- Investment rate4.132%
Inspect and compare dates
| Auction date | High discount rate | Investment rate |
|---|---|---|
| 4.050% | 4.132% | |
| 3.980% | 4.060% | |
| 3.990% | 4.071% | |
| 3.990% | 4.071% | |
| 3.920% | 3.999% | |
| 3.845% | 3.922% | |
| 3.750% | 3.824% | |
| 3.670% | 3.742% | |
| 3.655% | 3.727% | |
| 3.665% | 3.737% |
Show 14 more rows
| Auction date | High discount rate | Investment rate |
|---|---|---|
| 3.710% | 3.783% | |
| 3.675% | 3.747% | |
| 3.795% | 3.871% | |
| 3.650% | 3.722% | |
| 3.635% | 3.706% | |
| 3.650% | 3.722% | |
| 3.660% | 3.732% | |
| 3.640% | 3.712% | |
| 3.610% | 3.681% | |
| 3.610% | 3.681% | |
| 3.615% | 3.686% | |
| 3.600% | 3.671% | |
| 3.610% | 3.681% | |
| 3.595% | 3.665% |
Right now
High discount rate: 4.050% at the 8-week bill auction of , a reopening.
- Investment rate 4.132%
- Investment rate minus discount rate 8.2 basis points
Across auctions
4.050% is above the median of the 23 earlier 8-week bill auctions shown, 3.660%.
Of the 24 auctions shown, the highest was 4.050% on , the lowest 3.595% on .
Understanding discount rate vs investment rate on T-bills
Where it stands today
High discount rate: 4.050% at the 8-week bill auction of .
What does the term mean?
The discount rate of a Treasury bill is its discount from face value as a share of face value, on a year of three hundred and sixty days. The investment rate is what the price paid earns, on a calendar year; it is also called the bond-equivalent yield.
Read more
Why a bill has two rates
Bills pay no interest. They are sold below face value and pay face value at maturity. Bill auctions are bid in the discount rate, a convention from before computers. The investment rate restates the same price as a yield on the money actually paid, so it can be set next to a note or bond yield.
Which is higher
The investment rate is always higher. It divides by the price, which is below face value, and it counts a full calendar year. The gap grows with the rate and with the bill's length.
What to compare
- A bill against a note or bond: use the investment rate.
- A bill against earlier auctions of the same bill: either rate, as long as it is the same one each time. 500metrics names the rate in every sentence.
What it does not tell you
- What a buyer earns after tax or after selling before maturity. Both rates assume the bill is held to maturity.
Drafted with AI assistance from official sources; checked against the sources listed below.
The numbers behind the chart
What were the figures at the latest auction?8-week bill (reopening), 15 October 2026
| Figure | Value |
|---|---|
| High discount rate | 4.050% |
| Investment rate | 4.132% |
| Investment rate minus discount rate | 8.2 basis points |
Which pages show these figures?
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