Treasury Bills vs High-Yield Savings Accounts: How to Compare Your Options
Where should you keep $10,000 if you want it to earn money over the next three months? You could put it in a high-yield savings account or consider a short-term US Treasury bill. Both options can help your cash generate returns, but they work differently.
The trick is to look beyond the advertised interest rate. Your decision should also consider how soon you need the money, the taxes you may owe, the protection available and any fees involved.
1. How Do Treasury Bills and High-Yield Savings Accounts Work?
Treasury bills (T-bills) are short-term securities issued by the US government. They typically mature in 4 to 52 weeks and are generally sold at a discount to their face value. When a bill matures, the investor receives its face value. The difference between the purchase price and the amount received represents the return.
For example, if you buy a bill for $9,900 and receive $10,000 at maturity, your return is $100 before any applicable costs and taxes.
Learn more from TreasuryDirect's official Treasury bills guide.
High-yield savings accounts (HYSAs) are bank deposit accounts that generally pay more interest than many traditional savings accounts. Their rates are usually variable, meaning a bank can change the rate over time. Eligible deposits at FDIC-insured banks are protected up to applicable insurance limits.
Both options can be useful, but T-bills have maturity dates, while savings accounts generally allow withdrawals under the bank's account terms.
2. Treasury Bills vs High-Yield Savings Accounts
| Feature | Treasury bills | High-yield savings accounts |
|---|---|---|
| How you earn | Difference between purchase price and face value | Interest on your deposit |
| Typical term | 4–52 weeks | No fixed maturity |
| Return | Determined by purchase price and maturity value | Usually a variable interest rate |
| Access | At maturity or by selling before maturity | Withdrawals subject to account terms |
| Protection | Backed by the US government; not FDIC-insured deposits | Eligible deposits may be FDIC-insured |
| Taxes | Generally federally taxable; exempt from state and local income taxes | Interest generally subject to applicable income taxes |
| Potential costs | Brokerage fees or possible loss when selling early | Account fees or minimum balance requirements |
Sources: TreasuryDirect, TreasuryDirect on marketable securities and the FDIC.
3. A Dollar Example: What Could $10,000 Earn in 13 Weeks?
Let's compare the two options over 13 weeks using hypothetical rates for illustration. These are not live market quotations.
Suppose you have $10,000 and are considering:
- A high-yield savings account paying 4.00% APY.
- A 13-week Treasury bill with an illustrative annualised investment rate of 4.10%.
Option A: High-Yield Savings Account
Assume the account's 4.00% APY remains unchanged for the entire 13 weeks.
Step 1: Start with the formula
Interest = Initial deposit × [(1 + APY)^(13/52) − 1]
Step 2: Insert the figures
Interest = $10,000 × [(1.04)^(13/52) − 1]
Step 3: Calculate the result
Interest ≈ $98.53
Estimated earnings: $98.53
This calculation assumes the stated APY applies throughout the period and the money remains deposited under the account's terms.
Option B: Treasury Bill
Now assume a hypothetical annualised investment rate of 4.10%. For simplicity, we will use a straightforward 13-week calculation.
Step 1: Convert the percentage to a decimal
4.10% = 0.041
Step 2: Calculate the return
Return = $10,000 × 0.041 × (13/52)
Return = $102.50
Estimated return: $102.50
This is a simplified illustration. Actual Treasury bill pricing and yield conventions may produce a different result, so check the security's quoted yield and purchase price before investing.
How Do the Results Compare?
| Investment option | Estimated earnings over 13 weeks |
|---|---|
| High-yield savings account | $98.53 |
| Treasury bill | $102.50 |
| Difference | $3.97 |
Under these assumptions, the Treasury bill earns approximately $3.97 more before taxes and fees.
That is a small difference, and it does not automatically make the Treasury bill the better choice. The figures use different annualised return conventions, and the actual outcome depends on available rates, fees, taxes and account conditions. The example is intended to demonstrate the comparison process, not promise a particular return.
To check actual Treasury rates, consult TreasuryDirect's auction announcements and auction results.
4. How Quickly Can You Access Your Money?
A high-yield savings account may be more convenient when you need flexible access to your cash. However, transfer times, withdrawal conditions and account limits vary by bank.
A Treasury bill has a set maturity date. Holding it until maturity generally allows you to receive its face value. If you need your money earlier, you may be able to sell it through a bank or broker, but the selling price could be lower than what you paid. Transaction costs may also reduce your proceeds.
A useful rule is to match your investment to your timeline. Money needed for an unexpected expense may be better kept somewhere accessible, while money you can set aside until a known date may be suitable for a bill maturing around that time.
5. What About Taxes?
Treasury bill interest is generally subject to federal income tax but exempt from state and local income taxes. Interest earned in a savings account is generally taxable, with state and local treatment depending on your circumstances.
Your after-tax return depends on factors such as your tax bracket, state of residence and the investment's tax treatment. An investment with a slightly higher advertised yield may not leave you with more money after taxes and fees.
For more information, read the IRS guidance on interest income. Consult a qualified tax professional if you need a personalised calculation.
6. Your Decision Checklist
Before choosing between a Treasury bill and a high-yield savings account, ask yourself:
- When will I need the money? Match a Treasury bill's maturity to your planned spending date.
- How much flexibility do I need? Check withdrawal and transfer rules for savings accounts.
- Am I comparing equivalent returns? Understand APY and Treasury yield conventions.
- What fees apply? Include account charges, brokerage costs and potential selling expenses.
- What will I keep after taxes? Consider the different tax treatment of each option.
- What protection applies? Verify FDIC insurance for eligible bank deposits and remember that Treasury securities are not FDIC-insured deposits.
The Bottom Line
Treasury bills may suit money you can set aside until a known maturity date, while a high-yield savings account may be more convenient for cash you need to access flexibly.
Neither option is automatically better. Compare current rates, access, fees, taxes and return calculations before making your decision. The goal is not simply to chase the highest advertised number; it is to choose an option that fits your financial needs.
