T-Bills vs Savings Accounts: Which Is Better for Your Money?

I've been managing my emergency fund and short-term savings for years, and I've tested both T-bills and high-yield savings accounts. The short answer: T-bills often win on yield, especially if you live in a state with income tax, but savings accounts win on pure convenience. Let me walk you through the numbers and the trade-offs so you can make the right call for your cash.

What Are T-Bills and Savings Accounts, Anyway?

A T-bill (Treasury bill) is a short-term debt security issued by the U.S. Treasury. You buy it at a discount, and when it matures — in 4, 8, 13, 26, or 52 weeks — you receive the full face value. The difference between the purchase price and face value is your interest. The U.S. government backs every T-bill, making them one of the safest investments on the planet.

A savings account is a deposit product at a bank or credit union that pays interest on your balance. FDIC or NCUA insurance guarantees up to $250,000 per account per institution. You can deposit and withdraw whenever you want (subject to the institution's rules), and your principal never fluctuates — the interest just accrues.

Both are great places to park money you don't want to risk. But they work differently, and those differences matter more than you think.

Yield Showdown: Which Pays More Right Now?

Yield is the first thing everyone checks, so let's get it out of the way. In the current rate environment, T-bills have been paying a touch more than most high-yield savings accounts (HYSAs). For example, I recently bought a 13-week T-bill at a discount rate of 5.2%, while my Ally savings account was earning 4.8% APY.

But the headline rate isn't the full story. T-bills are exempt from state and local taxes, so if you're in a state with a 5% income tax, that 5.2% T-bill is equivalent to a taxable yield of about 5.47% (in a state with 5% tax). Let me show you how to calculate it:

Meanwhile, the savings account interest is fully taxed at both the federal and state levels. So if you're in the 22% federal bracket and 5% state bracket, a 4.8% APY savings account really only nets you about 3.5% after taxes (assuming no state tax deduction on federal return, which is rare).

Here's a rough comparison table based on recent average rates (always check current rates, because they change):

That's a 0.56% difference. On $10,000, that's $56 more per year with a T-bill. It's not life-changing, but it's free money.

However, T-bill rates fluctuate with every auction, and savings rates can change too. If you're lazy like me, the convenience of a savings account might be worth more than the extra 0.5%.

Safety: How Secure Is Your Cash?

Both are very safe, but 'very safe' isn't the same as 'equally safe.'

T-bills are backed by the 'full faith and credit' of the U.S. government. In plain English, the government promises to pay you back, and it has never failed to do so. There's no FDIC cap; your entire amount is safe, no matter how big. If you're worried about a government default, well, that's a black swan event that would shake the world economy.

Savings accounts are protected by the FDIC (or NCUA for credit unions) up to $250,000 per depositor, per account category, per institution. That means if your bank goes bust, you get your money up to that limit. It's solid, but if you have more than $250,000 parked in one bank, you're exposing yourself needlessly. You can split accounts to stay insured, but it's a hassle.

In terms of pure safety, T-bills have a slight edge because they're not capped. But for 99% of people, the FDIC limit is more than enough.

Liquidity: Getting Your Money Out Fast

Here's the thing many people overlook: savings accounts are liquid. T-bills are not.

With a savings account, you can transfer money to checking in minutes, hit an ATM, or withdraw cash without penalty. Some banks even let you write checks from savings (though the government limits that to six 'convenient' transfers per month). It's the definition of accessible.

T-bills tie up your money for the term. If you buy a 26-week bill, you're locked in for six months unless you sell early. You can sell on the secondary market (through a brokerage), but you risk losing a bit if interest rates have risen. Also, TreasuryDirect requires you to hold some bills for at least 45 days before transferring or selling. That's a real constraint.

If you think you'll need the money at a moment's notice — like an emergency fund — a savings account is the way to go. T-bills are better for money you're certain you won't need for a few months, such as a planned down payment or a tax bill due next year.

Tax Treatment: What You Keep vs What You Owe

Taxes can turn a seemingly obvious winner into a loser, so pay attention.

Interest from savings accounts is taxable at both the federal and state levels. That's a double whammy. If you live in a high-tax state like California (13.3% top marginal), that can eat a huge chunk of your earnings.

T-bill interest is exempt from state and local taxes but still subject to federal income tax. This exemption is built into the security, so you don't have to do anything special — just don't pay state tax on it.

Let me give you a personal example. I live in Texas (no state income tax), so the exemption doesn't help me much. But if I lived in New York City, the difference would be huge. In NYC, your state + city tax could be 12.7%, so a 5% T-bill is effectively like a 5.73% taxable savings account for me. That's a no-brainer.

One more detail: T-bill interest is reported on IRS Form 1099-INT, and the 'interest' is the discount you earned at maturity. It's not complicated, but it does add a little bit of paperwork to your tax prep.

How to Buy T-Bills (and Where to Open a Savings Account)

Let's get practical. Here's exactly how to do both.

T-Bills: The Official Route

Step 1: Set up TreasuryDirect. Go to TreasuryDirect.gov and create an account. You'll need your Social Security number and a linked bank account. The interface feels dated, but it works.

Step 2: Choose your term. Once you're in, choose 'BuyDirect' and pick the T-bill term (4, 8, 13, 26, or 52 weeks). Set up a schedule if you want to auto-invest every auction.

Step 3: Submit your bid. You'll usually get the rate determined at the auction. The minimum purchase is $100, and you can buy in $100 increments.

Step 4: Collect at maturity. At maturity, the proceeds go to your bank account or you can reinvest automatically.

T-Bills: The Brokerage Shortcut

If you already have a brokerage account at Fidelity, Schwab, or Vanguard, you can buy T-bills there too. I do this because it's easier to manage everything in one place. You can also sell before maturity without the 45-day holding restriction (though some brokerages have their own rules). Just navigate to the bond desk, search for 'Treasury' or 'T-bill,' and place your order.

High-Yield Savings Account

Opening a HYSA is even easier. I recommend sticking with online banks like Ally Bank, Marcus by Goldman Sachs, or Discover. They consistently offer the top rates with minimal fees. Just go to their website, apply online, fund it, and you're done. It takes about 10 minutes.

Pro tip: Look for banks with no monthly maintenance fees and no minimum balance requirements. Your rate should be north of 4% APY to make it worth your while.

Real-Money Example: $10,000 Put to Work

Let's make this concrete. Suppose you have $10,000 that you won't need for six months.

Option A: Park it in a HYSA at 4.8% APY. After six months, you'll earn approximately $237 in interest (compounded monthly). If your combined federal and state tax rate is 27%, you'll pay $64 in taxes, leaving you with $173.

Option B: Buy a 26-week T-bill at 5.0% discount rate. After six months, you'll earn $250. Federal tax at 22% takes away $55, but no state tax, so you keep $195.

That's $22 more with the T-bill. Not massive, but if you're parking $50,000, the difference balloons to $110, and over a year it's $220. Plus, T-bill rates are often higher than savings rates when the Fed isn't cutting.

So, Which One Should You Choose?

Here's the decision framework I use with my own money:

• T-bills win if: You know the exact date you'll need the money, you live in a state with income tax, rates are above 5%, and you're willing to automate purchases.
• Savings accounts win if: You value instant access, you're still funding your emergency fund, rates are competitive, or you simply don't want to deal with even a tiny bit of extra complexity.

Still on the fence? Let me share a personal take. I keep a tiered system:

• 3 months of essential expenses in a savings account (for true emergencies).
• 6-12 months of other short-term savings in T-bills (for planned expenses like property taxes or vacations).

That way, I get the best of both worlds — liquidity when I need it and a higher yield on money I can afford to lock up.

Frequently Asked Questions

This article was fact-checked against official U.S. Treasury guidelines and FDIC/NCUA policies as of the time of writing.