So you keep hearing people talk about treasury bills like they’re some kind of secret weapon, and you want to know what the fuss is about. Let me save you the corporate-speak: treasury bills are short-term IOUs from the US government that currently pay around 3.6% with effectively zero default risk. That’s it. That’s the whole pitch.
I’ll be honest — I ignored T-bills for years. After I blew up my first trading account in leveraged crypto and clawed my way back to sobriety and a real bank balance, I parked my recovery cash in a basic savings account earning 0.5%. For almost two years. When I finally sat down and ran the math on what I’d left on the table, I made a noise my dog still talks about in therapy.
This guide is what I wish someone had handed me back then. We’ll cover what T-bills actually are, how they work, current 2026 yields, the state tax angle nobody talks about, and exactly how to buy them. There’s also one trick most beginners miss that turns T-bills into truly hands-off passive income — I’ll get to that in the buying section.
Quick Answer: What Are Treasury Bills?
Treasury bills (T-bills) are short-term debt securities issued by the US government with maturities of 4 to 52 weeks. You buy them at a discount to face value, and at maturity you get the full face value back. The difference is your interest. Minimum purchase is $100. As of April 2026, 13-week T-bills yield about 3.60% — and that interest is exempt from state and local income taxes.
What Are Treasury Bills?
A treasury bill is a short-term loan you make to the US Treasury. The government borrows money from you, and after a set number of weeks they pay it back — with a little extra on top. That “little extra” is your return.
The thing that makes T-bills unique compared to other government debt is the discount structure. You don’t get monthly interest checks. Instead, you buy the bill for less than its face value, and you collect the full face value when it matures. Simple as that.
Minimum purchase is $100, and you can buy them in $100 increments. No fancy account, no trading platform required. The whole system was literally built so regular people could lend money to their own government.
T-Bills vs Treasury Notes vs Treasury Bonds
People mix these three up constantly, so let’s clear it up. The US Treasury issues three flavors of marketable debt, and the only real difference is how long the loan lasts:
- Treasury Bills (T-bills): 52 weeks or less. Sold at a discount, no coupon payments.
- Treasury Notes: 2 to 10 years. Pay interest every six months.
- Treasury Bonds: 20 to 30 years. Also pay interest every six months.
If you’ve ever wondered how bonds work, T-bills are basically the simplest, shortest cousin in that family. No coupon math, no duration risk to speak of, just a clean discount-and-redeem structure.
The Discount Purchase Mechanism Explained
Here’s the part that confuses people. Say you want to buy a $1,000 face-value, 13-week T-bill. The auction sets a price — let’s say $991.25. You pay $991.25 today. Thirteen weeks later, the Treasury deposits $1,000 into your linked bank account. You earned $8.75 on a $991.25 outlay over 13 weeks. Annualize that and you get roughly 3.55%.
That’s it. That’s the entire mechanism. No coupons, no reinvestment puzzles, no “what’s my YTM” calculations. You buy low, get face value back, pocket the difference.
How Treasury Bills Actually Work
The Treasury runs auctions on a regular schedule, and they offer six standard maturity terms. Knowing the calendar helps you plan around your cash needs.
Six Maturity Terms: 4 Weeks to 52 Weeks
The available T-bill maturities are:
- 4-week, 8-week, 13-week, 17-week: auctioned weekly
- 26-week: auctioned weekly
- 52-week: auctioned every four weeks
The shorter the term, the closer the yield tracks the federal funds rate. Longer T-bills can pay slightly more or less depending on what the market thinks the Fed will do over the next year. As of late April 2026, the curve is roughly flat — 4-week bills around 3.65% and 13-week around 3.60%, per the US Department of the Treasury daily bill rates.
How to Calculate Your Return (Simple Example)
Let me show you with real numbers. Say you have $5,000 you don’t need for the next three months. You buy a 13-week T-bill at the current rate.
- Face value purchased: $5,000
- Discounted purchase price: approximately $4,956.25
- Cash out today: $4,956.25
- At maturity (13 weeks later): $5,000 deposited back
- Your earnings: $43.75
That $43.75 sounds small until you realize it’s three months of doing absolutely nothing. Annualized, you’re earning about 3.6% on cash that would’ve earned you maybe $6 in a brick-and-mortar savings account. Compounded across five-figure balances, this adds up faster than people think.
One quick note: when you place a non-competitive bid (which any normal person should), you automatically receive whatever rate the auction settles at. You can place non-competitive bids up to $10 million per auction, so don’t worry about hitting limits.
Why Investors Choose Treasury Bills
The case for T-bills isn’t sexy. It’s boring. And boring is the whole point. Let me walk you through the actual reasons people use them.
Zero Default Risk: Backed by the Full Faith of the US Government
T-bills are backed by the full faith and credit of the United States government. In plain English: for the US to default on a T-bill, the entire federal government would have to collapse. Could that happen? Theoretically. But if it does, the dollars in your savings account aren’t going to be worth much either, so we’re solving for a different problem at that point.
You don’t need FDIC insurance with T-bills. The Treasury is the backstop. That’s actually stronger than the $250,000 cap that protects bank deposits.
The State Tax Advantage Most People Overlook
This is the part that made me want to build a time machine and slap my younger self. Interest from T-bills is exempt from state and local income taxes. Federal tax still applies, but if you live in a high-tax state, this is huge.
“Don’t overlook the state tax exemption on U.S. Treasury income — it could be costly.” — WisdomTree Investment Team, February 2026
Run the numbers yourself. If you live in California (top rate 13.3%), New York (10.9%), or New Jersey (10.75%), and you earn $1,000 in interest from a high-yield savings account, you’re handing $100 or more to your state every year. Earn that same $1,000 from T-bills? Your state gets nothing. The IRS confirms this treatment in IRS Topic 403 on interest income.
I tell my community to think of this as a “stealth yield bump.” If you’re in a 9% state bracket, a 3.6% T-bill is roughly equivalent to a 3.95% taxable HYSA on an after-tax basis. Pair this with smart tax efficiency strategies and you start keeping a meaningful chunk of every dollar you’d otherwise hand over.
Treasury Bills vs High-Yield Savings Accounts in 2026
This is the comparison I get asked about constantly. The honest answer is that they serve different jobs. Let me lay it out.
| Feature | Treasury Bills | High-Yield Savings |
|---|---|---|
| Current yield (Apr 2026) | ~3.60% | 3.5% – 4.5% APY |
| State tax | Exempt | Taxable |
| Liquidity | Wait or sell on secondary | Instant access |
| Best for | Cash parked 1–6 months | Emergency fund |
If you’re building or maintaining your emergency fund, that money belongs in a high-yield savings account. Period. You need it accessible the moment your transmission gives out or your dog eats a sock.
But for cash you’ve earmarked for something specific 2 to 6 months out — a tax bill, a down payment timeline, a planned big purchase — T-bills usually win on after-tax yield, especially in high-tax states. As one financial education team put it: “For cash you will not need for three months or longer, Treasury bills become more attractive, as the combination of competitive yields and tax savings makes them ideal for money earmarked for future goals.”
How to Buy Treasury Bills: Two Proven Methods
There are two real ways to buy T-bills, plus a lazy ETF option. I’ve used all three depending on the situation.
Method 1: TreasuryDirect.gov (Best for Most Investors)
TreasuryDirect is the government’s own platform. No middleman, no commissions, no expense ratio. You’re buying directly from the source. The full reference is on the TreasuryDirect Treasury Bills page.
Here’s the actual flow:
- Go to TreasuryDirect.gov and create an account (you’ll need your SSN, bank account, and a working email)
- Link your bank account for funding and redemptions
- Click BuyDirect, then select Bills
- Pick your maturity term (4-week, 8-week, 13-week, etc.)
- Enter the dollar amount in $100 increments
- Choose non-competitive bid — this guarantees you get the auction rate
- Submit and wait for the next scheduled auction
The Trick I Promised You: Auto-Reinvestment
When you place your order, look for the “schedule reinvestment” option. Toggle it on. Every time your T-bill matures, TreasuryDirect will automatically roll the proceeds into a new T-bill of the same term at the new auction rate. Set it once and it runs itself. This is how T-bills actually become passive income — without this setting, you’re going to forget and let cash sit idle.
Method 2: Through a Brokerage Account (More Flexibility)
If you already have a brokerage account at Fidelity, Schwab, or Vanguard, you can buy T-bills there too. The advantages: you can sell on the secondary market before maturity if you need cash, and you can hold T-bills alongside your other investments in one place.
The trade-offs are minor. Brokerages sometimes show slightly different yields because of how they handle the auction, but the underlying security is identical. I personally use Fidelity for T-bill purchases when I want them sitting next to my other positions.
Treasury Bill ETFs: The Set-It-and-Forget-It Option
If even TreasuryDirect feels like too much friction, T-bill ETFs solve the problem with one ticker. The two big ones:
- SGOV — iShares 0–3 Month Treasury Bond ETF
- BIL — SPDR Bloomberg 1–3 Month T-Bill ETF
You buy these like any stock. Daily liquidity, monthly distributions, and the fund handles the rolling for you. The catch is a small expense ratio (around 0.07–0.14%) that nibbles a few basis points off your yield. For a lot of people, that’s worth the simplicity.
Who Should (and Shouldn’t) Invest in Treasury Bills
Let me be brutally honest, because the financial internet rarely is. T-bills are not a wealth-building tool. They’re a cash management tool. Knowing the difference is what separates people who use them well from people who let inflation quietly eat their savings.
T-Bills Are Ideal For
- Investors in high-tax states (CA, NY, NJ, OR, MA) who want better after-tax yield on idle cash
- Cash parked for 1 to 6 months — saving for a known expense like taxes, tuition, or a planned purchase
- Conservative savers who want zero credit risk and a known maturity date
- The overflow on top of a fully funded emergency fund
T-Bills Are NOT Ideal For
- Long-term wealth building — you need index funds and equity exposure for that
- People who need daily liquidity for unexpected expenses
- Anyone who needs predictable monthly income — T-bills pay at maturity, not monthly. Look at dividend investing or REITs for that
- Inflation-sensitive long-term savings — if CPI runs above 3.6%, your real return goes negative
The way I think about it: T-bills are the safe cash layer, sitting on top of everything else. Below them you’ve got your Roth IRA, your 401(k), and your taxable brokerage with steady dollar cost averaging into broad index funds. T-bills replace nothing. They round out the picture.
I’ll mention the inflation point one more time because it matters. Look at 3-Month Treasury Bill rate historical data against CPI over the last few decades. There are long periods where T-bill yields lost to inflation. Real return — what your money actually buys — went negative. That’s not a flaw in T-bills, it’s a feature of low-risk assets. You trade upside for safety. Always have, always will.
Frequently Asked Questions About Treasury Bills
Are Treasury bills completely safe?
If held to maturity, T-bills carry effectively zero default risk — they’re backed by the full faith and credit of the US government. The one way you can lose money is by selling them on the secondary market before maturity in a rising-rate environment, where their resale price drops below what you paid.
Do T-bills pay interest monthly?
No. T-bills don’t pay periodic interest at all. You buy them at a discount and receive the full face value at maturity. Your “interest” is the difference. If you want monthly cash flow, T-bill ETFs like SGOV or BIL distribute monthly, but the underlying bills themselves do not.
What happens when a T-bill matures?
The face value gets deposited into your linked bank account (if you bought through TreasuryDirect) or into your brokerage cash position. If you enabled auto-reinvestment, the proceeds automatically roll into a new T-bill at the next auction. If you didn’t, the cash just sits there earning nothing — which is a great way to leak yield, so set the reinvestment flag.
Can I lose money on Treasury bills?
Yes — but only in two scenarios. First, if you sell on the secondary market before maturity and rates have risen since you bought (the bill’s resale price drops). Second, in real terms, if inflation outpaces your T-bill yield, your purchasing power decreases even though your nominal dollars increased. Held to maturity in a stable inflation environment, you cannot lose money in nominal terms.
Final Thoughts
Treasury bills aren’t going to make you rich. They’re going to make sure your idle cash is doing more than rotting in a 0.5% savings account, the way mine did for too long. That’s a meaningful job, and it’s one that T-bills happen to do exceptionally well — especially after the state tax angle is factored in.
If you’re sitting on cash you don’t need for a few months, building T-bills into your routine is one of the lowest-effort yield bumps available to retail investors. Set up a TreasuryDirect account this weekend, link your bank, place a non-competitive bid for your next maturity, and toggle auto-reinvestment. Total time investment: maybe 20 minutes. Then it runs itself.
If you’re newer to building a full portfolio, T-bills are just one piece. The next steps I’d point you toward are learning how to invest in index funds for long-term growth, and dialing in your emergency fund. T-bills are the safe cash layer that sits on top of all of that — they don’t replace any of it.
Hit me up in the community if you have questions about which maturity to start with, or how to think about T-bills inside your overall plan. I’ve made enough mistakes with my own money that I’m cheaper than a financial advisor and more honest than most.
