US Treasury bills are short-term government debt instruments issued by the US Department of the Treasury with maturities ranging from four weeks to one year. They are sold at a discount to their face value and pay no periodic interest; instead, investors earn the difference between purchase price and redemption value at maturity.
These securities are among the safest investments available because they are backed by the full faith and credit of the United States government. The US Treasury auctions T-bills weekly through the TreasuryDirect platform and primary dealers, making them accessible to individual investors, institutions, and foreign governments alike.
For example, a $10,000 T-bill maturing in 13 weeks might be sold for $9,850. At maturity, the investor receives $10,000, earning $150 in profit. This return is guaranteed by the federal government, making T-bills a preferred choice for risk-averse savers and institutions managing liquidity.
Treasury bills operate on a discount basis. Unlike bonds that pay regular interest, T-bills do not have coupon payments. Instead, the return is embedded in the difference between the purchase price and the face value paid at maturity.
The auction process determines the discount rate. Bidders submit competitive bids (specifying the yield they're willing to accept) or non-competitive bids (accepting the average yield of successful competitive bids). Non-competitive bidders are guaranteed acceptance up to $5 million per auction.
For instance, during a May 2024 auction, 13-week T-bills were issued at a discount yielding 4.85%. An investor buying $100,000 in T-bills would pay approximately $98,787.50 and receive $100,000 upon maturity, netting $1,212.50 in interest-free earnings.
US Treasury bills are categorized by their time to maturity:
| Maturity | Typical Auction Frequency | Common Use |
|---|---|---|
| 4 weeks | Weekly | Cash management for businesses and individuals |
| 13 weeks (3 months) | td>WeeklyShort-term savings and portfolio liquidity | |
| 26 weeks (6 months) | Biweekly | Stable returns with moderate duration risk |
| 52 weeks (1 year) | Biweekly | Longer-term cash preservation with minimal volatility |
Each maturity option allows investors to align their capital deployment with specific financial goals. For example, a university endowment might allocate funds to 26-week T-bills to preserve principal while awaiting a larger grant disbursement.
Financial institutions, corporations, and individual investors use US Treasury bills as a safe haven during market volatility. According to the Federal Reserve Bank of New York, T-bills accounted for nearly 40% of all US government debt outstanding in 2023 due to their liquidity and safety.
Central banks also hold T-bills as part of their reserve assets. The European Central Bank reported holding $120 billion in US T-bills as of Q1 2024, citing their role in maintaining stable foreign exchange reserves.
Investors often use T-bills to rebalance portfolios during downturns. During the 2020 market sell-off, retail investors increased T-bill holdings by 32% compared to the prior quarter, according to data from the Securities Industry and Financial Markets Association (SIFMA).
Many assume T-bills pay interest monthly or quarterly. This is incorrect. T-bills do not pay periodic interest. All returns come from the discount at purchase and face value at maturity.
Another misconception is that T-bills are taxable only at maturity. While the IRS treats the discount as taxable income annually under the "imputed interest" rule, most investors report the accrual each year even though no cash is received until maturity.
A lesser-known fact: T-bills are not traded on secondary markets like stocks or corporate bonds. They are held until maturity unless sold early through TreasuryDirect, which incurs a fee and may result in a loss if market rates have risen since purchase.
I purchased a 13-week T-bill through TreasuryDirect in January 2023. The site displayed a yield of 4.2%, and I invested $5,000. When the bill matured, I received $5,105.25. The system automatically deposited the amount into my linked bank account. No paperwork, no waiting. The entire process took less than five minutes to initiate.
This experience confirmed how straightforward and secure T-bills are for small investors seeking a low-effort, low-risk way to grow idle cash.
While T-bills are short-term, other Treasury securities differ in structure and purpose:
Unlike T-bills, notes and bonds expose investors to interest rate risk and reinvestment risk. T-bills avoid these issues due to their short duration and lack of interim payments.
Although T-bills don't pay interest in the traditional sense, the effective annualized yield reflects the return earned. This yield is calculated using the discount rate and the time to maturity.
For example, a $10,000 T-bill purchased for $9,800 with a 13-week maturity yields 8.16% annually. The calculation uses the formula: [(Face Value - Purchase Price) / Purchase Price] × (365 / Days to Maturity).
What are US Treasury bills? They are low-risk, short-term government securities that provide a reliable return with minimal volatility. Their backing by the US government makes them a foundational element of personal and institutional portfolios.