Key Takeaways
Direct answer: A Treasury bill is short-maturity U.S. government debt, issued at a discount to face value with a maturity of one year or less, that functions as a cash equivalent because it is highly liquid, short-dated, and backed directly by the U.S. government. It carries no FDIC or NCUA insurance, and while held-to-maturity investors receive the stated face value, a bill sold before maturity is subject to market-price movement.
- A Treasury bill is one of the two instruments, alongside money market funds, most commonly treated as a true cash equivalent under the standard three-part test.
- It is not FDIC or NCUA insured; its safety comes from the direct backing of the U.S. government instead of deposit insurance.
- Interest income from a Treasury bill is exempt from state and local income tax, though it remains subject to federal income tax.
- Held to maturity, a bill returns its stated face value; sold early on the secondary market, its price can be above or below the original purchase price.
A Treasury Bill as a Cash-Equivalent Choice
A Treasury bill earns its place as a cash equivalent by satisfying the same three-part test covered on Swoopr's What Counts as a Cash Equivalent? guide: high liquidity, since bills trade in a deep secondary market and can also be purchased directly through TreasuryDirect with maturities as short as a few weeks; short original maturity, since a bill's maturity at issuance is one year or less; and minimal price risk, since the direct backing of the U.S. government and the bill's short duration limit how much its price can move before maturity. Investors access Treasury bills either directly through TreasuryDirect at auction or through a bank, broker, or dealer on the secondary market.
Treasury Bills vs. Savings Accounts and CDs
| Feature | Treasury bill | Savings account | CD |
|---|---|---|---|
| Backing | Direct U.S. government backing, no dollar cap | FDIC or NCUA, $250,000 standard limit | FDIC or NCUA, $250,000 standard limit |
| State/local tax | Interest exempt | Interest fully taxable | Interest fully taxable |
| Yield source | Set at auction, tracks market rates | Set by the bank | Fixed for the term at purchase |
| Liquidity before term ends | Sellable on secondary market, price can move | On demand, no price risk | Early-withdrawal penalty, no market-price risk |
The core trade-off mirrors the money market fund comparison elsewhere on this hub: a Treasury bill exchanges deposit insurance for a different form of protection, the direct backing of the federal government with no dollar cap, plus a state-and-local tax exemption that a bank deposit product does not offer, in exchange for accepting some market-price risk if sold before maturity.
Backing Status: U.S. Government, Not FDIC or NCUA
A Treasury bill is not FDIC insured and not NCUA insured, because it is not a bank or credit union deposit product at all. Its safety comes instead from the direct backing of the U.S. government's ability to pay, a fundamentally different form of protection than deposit insurance: there is no $250,000 dollar cap on a Treasury bill's backing, but there is no guarantee against a price change if the bill is sold on the secondary market before maturity, unlike the price stability an FDIC- or NCUA-insured deposit account provides up to its coverage limit.
Where to Go for Full Mechanics
This page intentionally does not re-explain Treasury auctions, the full range of marketable Treasury securities, duration, or the yield curve, since Swoopr's Fixed Income & Bonds hub already covers Treasury securities in that depth as part of its broader fixed-income curriculum. Consult that page for the full treatment; this page exists to answer the narrower question of how a Treasury bill functions specifically as a cash-equivalent choice next to the bank deposit products and money market fund covered elsewhere on this hub.
Frequently Asked Questions
Are Treasury bills FDIC insured?
No. A Treasury bill is not a bank deposit and carries no FDIC or NCUA insurance. Its safety instead comes from the direct backing of the U.S. government's ability to pay, a different form of protection than deposit insurance, with no $250,000 dollar cap but with its own market-price risk if sold before maturity.
Can a Treasury bill lose value?
A Treasury bill held to maturity returns its stated face value, so there is no loss of principal if it is held that long. If sold on the secondary market before maturity, its price can be above or below what was paid, moving with prevailing short-term interest rates, so a Treasury bill sold early is not guaranteed to return the original purchase price.
How do Treasury bills compare to a savings account or CD for cash needs?
A Treasury bill offers direct U.S. government backing with no dollar cap, interest exempt from state and local income tax, and a yield set at auction, but no FDIC or NCUA insurance and a settlement and secondary-market process rather than instant, on-demand access. A savings account or CD offers instant or scheduled access with FDIC or NCUA insurance up to $250,000 per depositor, per institution, per ownership category, but is fully subject to state and local income tax and pays a rate the bank sets rather than a market-auction rate.
How does a Treasury bill produce a return if it pays no coupon?
Bills are sold at a discount to face value and redeem at face value, so the return is the difference between the purchase price and the amount received at maturity rather than periodic interest payments. A bill bought below face and held to maturity produces a known dollar gain on a known date. That gain is treated as interest income for tax purposes even though no interest was paid along the way, which is what keeps the state tax exemption applicable.
What is the difference between the discount rate and the investment rate quoted at a bill auction?
They describe the same auction result on two different conventions. The discount rate expresses the return as a percentage of face value on a 360-day basis, which is the traditional money-market convention. The investment rate, sometimes called the coupon-equivalent yield, expresses it as a percentage of the price actually paid on a 365-day basis, so it is directly comparable to a bank APY or a bond yield. The investment rate is the one that lines up with other cash yields.
Can Treasury bills be bought outside of an auction?
Yes. Bills trade in a large secondary market, so a brokerage account can buy an already-issued bill at any point in its life at a market price rather than waiting for an auction date. That allows a maturity to be matched to a specific spending date rather than to the auction calendar. Auction purchases avoid a dealer spread; secondary purchases add flexibility on timing and maturity, and the two routes can be used together.
What happens if money is needed early from a bill held at TreasuryDirect?
TreasuryDirect holds securities but does not operate a secondary market, so a bill held there cannot simply be sold within the platform. Selling before maturity requires transferring the holding to a brokerage account first, a process that takes time and paperwork. A bill held in a brokerage account from the start can be sold at the prevailing market price on any trading day. Where the bill is held therefore determines how quickly it can be turned into cash.
How is Treasury bill income reported at tax time?
Interest from a bill is reported on Form 1099-INT for the year the bill matures or is sold, in the box that identifies interest on US savings bonds and Treasury obligations. That separate reporting is what lets a state return identify the exempt portion. A bill sold before maturity can also produce a capital gain or loss on the price change, which is reported separately from the interest component.
Do Treasury bills carry any risk around a debt ceiling standoff?
The credit backing does not change, but the timing of payment can become a live question when a statutory borrowing limit is being contested. In past episodes, bills maturing close to a projected exhaustion date have traded at higher yields than neighboring maturities, which is the market pricing uncertainty about prompt payment rather than about eventual repayment. Selecting maturities away from such dates is the usual response for cash that is needed on a fixed schedule.