Every Treasury bill starts life at a public auction, and the rules are short and published: who may bid, how bids are ranked, what each winner pays and when the money moves. The rules below come from the Treasury's auction regulations and help pages, and the worked examples use real results from October 2026. For what a bill is and how it is priced, see what is a Treasury bill?; for every other Treasury topic, the Treasuries hub.
What happens in a Treasury auction?
Each auction runs in four steps: Treasury announces it, takes bids until a deadline on auction day, awards the bills at one rate, and settles on the issue date.
The announcement names the security, the amount offered, the auction, issue and maturity dates, the closing times for both kinds of bid and the terms of the offering. TreasuryDirect refreshes its list of upcoming auctions every Friday by 10:45 a.m. Eastern time. Four times a year, usually on the first Wednesday of February, May, August and November, the Treasury holds its quarterly refunding press conference and releases a tentative auction schedule for the next six months.
For bills, the bidding window normally shuts at 11:00 a.m. Eastern for noncompetitive tenders and 11:30 a.m. for competitive ones. When a holiday stacks auctions onto one day, the deadlines are staggered. On Tuesday, October 13, 2026, the day after Columbus Day, the 13- and 26-week bills closed at the usual times while the 6-week bill closed at noon and 1:00 p.m.
Treasury releases the results the same day, and anyone who bid through TreasuryDirect can see their own result in the account after 5 p.m. Eastern. On the issue date the bills are delivered and paid for: TreasuryDirect debits the linked bank account, and a broker takes the money from your cash balance. Here is how those dates fell for one bill:
- Announced: Thursday, October 8, 2026, for $82 billion of 26-week bills
- Auctioned: Tuesday, October 13, moved from Monday by the holiday
- Issued and paid for: Thursday, October 15
- Matures: Thursday, April 15, 2027
What is the difference between competitive and noncompetitive bids?
A noncompetitive bid takes whatever rate the auction sets and is filled in full; a competitive bid names a rate and wins only if that rate is low enough.
| Noncompetitive bid | Competitive bid | |
|---|---|---|
| What you state | Only the amount | The amount and a discount rate, to three decimals in steps of 0.005 |
| Limit per auction | $10 million | 35% of the offering amount, less any net long position you already hold |
| When it is filled | First, in full | After noncompetitive bids, from the lowest rate upward |
| Chance of getting nothing | None, if the bid follows the rules | Yes, if your rate is above the high rate |
| Rate you receive | The high rate | The high rate, even if you bid lower |
| How you place it | TreasuryDirect, or a bank, broker or dealer | A bank, broker or dealer, or Treasury's auction system for approved institutions |
| Usual deadline for bills | 11:00 a.m. Eastern time | 11:30 a.m. Eastern time |
You can bid one way or the other in a given auction, not both. Noncompetitive bids are capped at $10 million per auction, and they are a small slice of most bill auctions: $1.9 billion of the $82 billion 26-week offering on October 13, 2026, and $5.6 billion of the $110 billion 4-week offering two days later.
A single competitive bidder can win no more than 35% of the offering amount, reduced by any net long position it reports in the bill, and Treasury ignores whatever one bidder offers above that cap at any single rate. The limit exists to stop one firm from cornering an issue, and it is why bidders must report large positions they already hold through when-issued trades or futures.
How does Treasury set the winning rate?
Treasury fills noncompetitive bids first, then accepts competitive bids from the lowest rate up; the last rate needed to sell the offering becomes everyone's rate.
That last rate is called the high rate or stop-out rate, and every winner, competitive or not, pays the price it implies. Treasury moved all bill, note and bond auctions to this single-price method in November 1998, after testing it on 2- and 5-year notes from September 1992. Announcing the change, Assistant Secretary Gary Gensler said it spread awards more widely and let bidders bid more aggressively, because they "pay only the price of the lowest accepted bid, rather than the actual price they bid." Before that, bill buyers paid the price of their own bids.
Bids placed at exactly the high rate usually cannot all be filled, so Treasury shares out whatever is left:
Share filled at the high rate = amount still unsold after lower bids ÷ total bid at the high rate
The percentage is rounded up to the next hundredth of a percent, each award is rounded up to the next $100, and the price is calculated to six decimal places per $100 of face value.
Worked example: Finding the high rate in a $10 billion 26-week auction
Treasury offers $10.0 billion. Noncompetitive bids total $0.6 billion and are filled first, leaving $9.4 billion for competitive bidders, whose bids are ranked from the lowest rate up.
| Discount rate bid | Amount bid | Running total | Outcome |
|---|---|---|---|
| 4.150% | $1.5 billion | $1.5 billion | Filled in full |
| 4.160% | $2.0 billion | $3.5 billion | Filled in full |
| 4.170% | $2.5 billion | $6.0 billion | Filled in full |
| 4.175% | $1.8 billion | $7.8 billion | Filled in full |
| 4.180% | $2.4 billion | $10.2 billion | Partly filled; this is the high rate |
| 4.185% | $5.0 billion | $15.2 billion | Rejected |
| 4.190% | $6.0 billion | $21.2 billion | Rejected |
| 4.200% | $4.0 billion | $25.2 billion | Rejected |
- Room left at 4.180%: $9.4 billion − $7.8 billion = $1.6 billion
- Share of each 4.180% bid filled: $1.6 billion ÷ $2.4 billion = 66.67%, so a $100 million bid at that rate receives $66.67 million
- Price for every winner: 100 × (1 − 0.0418 × 182 ÷ 360) = 97.886778 per $100, so a $10,000 noncompetitive bid costs $9,788.68
- Bid-to-cover: ($0.6 billion + $25.2 billion) ÷ $10.0 billion = 2.58
The bidder that asked for only 4.150% still receives 4.180%, and the bidders at 4.185% and above get nothing.
How do you read Treasury auction results?
Start with the high rate, which every winner receives, then use the bid-to-cover ratio and the share allotted at the high rate to judge how strong demand was.
Here is the October 13, 2026 auction of 26-week bills from Treasury's results data:
| Result line | Value | What it tells you |
|---|---|---|
| High discount rate | 4.200% | The rate every winning bidder receives |
| Investment rate | 4.351% | The same result as a yield on the cash invested |
| Price per $100 | 97.876667 | What $100 of face value cost |
| Low rate | 4.100% | The lowest competitive rate accepted |
| Median rate | 4.175% | Half of the accepted competitive amount was bid at or below this rate |
| Allotted at the high rate | 78.17% | The share of each bid at exactly 4.200% that was filled |
| Bid-to-cover ratio | 2.76 | $226.7 billion of public bids for $82 billion on offer |
| Noncompetitive awards | $1.9 billion | Filled in full at the high rate |
| Federal Reserve add-on | $4.7 billion | Issued to the Fed on top of the $82 billion |
The bid-to-cover ratio leaves the Fed out of both sides. Total tenders were $231.35 billion, including the Fed's $4.66 billion rollover, so the public bid $226.69 billion for the $82 billion offered: 226.69 ÷ 82 = 2.76. A higher ratio means more bids chasing each dollar of bills, and a high allotment at the stop-out rate means fewer bids were crowded at the margin.
The two rate lines are the same result in two conventions. The discount rate is measured against face value over a 360-day year, while the investment rate is measured against the price you pay over a 365-day year, which is why it is higher; the discount rate vs investment rate guide shows the conversion.
The table below lists the most recent bill auctions in the site's data feed, one row per auction. Compare each term with its own recent history rather than with other terms, since a 4-week bill and a 52-week bill draw different buyers. If the feed is unavailable, the table says so, and the same figures are on TreasuryDirect and in Fiscal Data's auction dataset.
| Auction date | Bill | High discount rate | Investment rate | Bid-to-cover | Offering size |
|---|---|---|---|---|---|
| Oct 15, 2026 | 8-Week bill | 4.050% | 4.132% | 2.26 | $105B |
| Oct 15, 2026 | 4-Week bill | 4.000% | 4.068% | 2.56 | $110B |
| Oct 14, 2026 | 17-Week bill | 4.195% | 4.313% | 2.79 | $75B |
| Oct 13, 2026 | 6-Week bill | 3.980% | 4.055% | 2.58 | $95B |
| Oct 13, 2026 | 26-Week bill | 4.200% | 4.351% | 2.76 | $82B |
| Oct 13, 2026 | 13-Week bill | 4.085% | 4.185% | 2.68 | $95B |
| Oct 8, 2026 | 4-Week bill | 3.980% | 4.048% | 2.40 | $110B |
| Oct 8, 2026 | 8-Week bill | 3.980% | 4.060% | 2.77 | $105B |
Each row gives the high discount rate and the matching investment rate, the bid-to-cover ratio and the offering size, which is the amount Treasury announced before any Federal Reserve add-on. A run of falling ratios for one term over several weeks says more about demand than any single auction.
Who are primary dealers, direct bidders and indirect bidders?
Primary dealers are the 25 firms that trade with the New York Fed and are expected to bid in every auction; direct and indirect bidders are the other competitive bidders.
The New York Fed expects each primary dealer to bid for its pro-rata share of every auction, the amount auctioned divided by the number of dealers, at reasonably competitive prices. With 25 dealers that share is 4%, or about $3.3 billion of an $82 billion 26-week offering. The list changes: NatWest Markets Securities withdrew on October 16, 2026, and MUFG Securities Americas joined on January 15, 2026.
Treasury's results split the competitive awards three ways. A direct bidder is a firm other than a primary dealer that submits bids for its own account straight into Treasury's auction system. An indirect bidder is a customer bidding through a primary dealer or another direct submitter, a group that includes foreign central banks and other monetary authorities bidding through the New York Fed. Neither label says whether the bidder is foreign or domestic.
At the October 13, 2026 auction of 26-week bills, $79.5 billion of competitive bids were accepted. Indirect bidders took $52.7 billion (66.3%), primary dealers $18.5 billion (23.2%) and direct bidders $8.3 billion (10.5%). Because dealers bid for their full share at prices near the market, their awards shrink when other bidders bid lower rates and grow when other bidders hold back.
The Federal Reserve is not in any of those groups. When bills in its portfolio mature, the New York Fed rolls them into new bills with noncompetitive bids that Treasury adds on top of the announced size, split across the bills issued that day in proportion to their offering amounts. Bills maturing on Tuesdays (4-, 8- and 17-week) roll into Tuesday issues, and those maturing on Thursdays (6-, 13-, 26- and 52-week) into Thursday issues. The add-ons receive the high rate and do not change it.
When are Treasury bills auctioned?
Treasury auctions six bill terms every week and the 52-week bill every four weeks, each on a fixed pattern of announcement, auction and issue days.
| Bill | Announced | Auctioned | Issued |
|---|---|---|---|
| 4-week and 8-week | Tuesday | Thursday of the same week | The following Tuesday |
| 17-week | Tuesday | Wednesday | The following Tuesday |
| 6-week | Thursday | The following Tuesday | Thursday |
| 13-week and 26-week | Thursday | The following Monday | Thursday |
| 52-week, every four weeks | Thursday | The following Tuesday | Thursday |
| Cash management bills | When needed | Usually one to several days later | Shortly after the auction |
If an issue date lands on a weekend or federal holiday, the bills are issued on the next business day, and holidays push auctions back too. Treasury also warns that its borrowing needs, policy decisions and congressional action on the debt limit can change the pattern.
Worked example: One week of bill auctions: October 13 to 15, 2026
| Auction day | Bill | Offered | High rate | Bid-to-cover |
|---|---|---|---|---|
| Tuesday, October 13 | 6-week | $95 billion | 3.980% | 2.58 |
| Tuesday, October 13 | 13-week | $95 billion | 4.085% | 2.68 |
| Tuesday, October 13 | 26-week | $82 billion | 4.200% | 2.76 |
| Wednesday, October 14 | 17-week | $75 billion | 4.195% | 2.79 |
| Thursday, October 15 | 4-week | $110 billion | 4.000% | 2.56 |
| Thursday, October 15 | 8-week | $105 billion | 4.050% | 2.26 |
- Offered in total: $95 + $95 + $82 + $75 + $110 + $105 = $562 billion
- Federal Reserve add-ons across the six auctions: $35.0 billion
- Issued in total: $562 billion + $35.0 billion = $597.0 billion, in three business days
To price any of those bills for your own amount, run its high rate through the calculator.
What are cash management bills?
Cash management bills are extra bills Treasury sells outside the regular calendar when it needs cash for days or weeks, usually announced, auctioned and issued within a few days.
They have existed since 1974, and their terms are set case by case. The most recent before this page was reviewed was a 27-day bill announced on May 20, 2026, auctioned on May 21 and issued on May 22: $25 billion at a 3.605% high rate, with a bid-to-cover ratio of 4.60, maturing on June 18. Treasury held 57 cash management bill auctions in 2024, according to Fiscal Data.
Individuals cannot buy them in TreasuryDirect; bids go through a bank, broker or dealer. Two of today's regular terms grew out of them: Treasury had sold 17-week and 6-week maturities as cash management bills before the first regular 17-week bill was issued on October 25, 2022 and the first regular 6-week bill on February 20, 2025.
What are the risks of buying at a Treasury auction?
The main auction risks are learning your rate only after bidding closes, a partial or empty fill on a competitive bid, and being committed once the deadline passes.
- Rate uncertainty. A noncompetitive bid accepts whatever the auction produces. The October 13, 2026 auction of 26-week bills stopped at 4.200%, while the 26-week bill had traded at a 4.18% discount rate on the previous business day; the result can land above or below recent market levels.
- Partial or no fill. Competitive bids above the high rate get nothing, and bids at the high rate get only their pro-rata share, 78.17% at that auction.
- Commitment and funding. After the deadline a bid cannot be withdrawn. TreasuryDirect takes the money on the issue date and cancels the purchase if the funds are not there, and brokers often set order cutoffs earlier than Treasury's.
- Market risk after you own the bill. Its price moves with rates until maturity, inflation can outrun its yield, and the next auction may set a lower rate when you roll over. Are Treasuries risk-free? covers each of these, selling Treasuries before maturity explains early exits, and what happens when a T-bill matures covers rollovers.
None of this changes the backing: bills bought at auction are backed by the full faith and credit of the US government. To place a bid, see how to buy Treasury bills for the four ways to buy and the TreasuryDirect account guide for setting up a direct account; a T-bill ladder shows how regular auctions can be used to stagger maturities.