T-Bills vs. High-Yield Savings Calculator
Which earns more after taxes? Enter your savings APY and tax rates. The T-Bill yield is pre-filled with the latest official rate.
T-Bills vs. high-yield savings calculator
T-Bill interest is subject to federal income tax but exempt from state and local income taxes; savings interest is taxed at all levels. Assumes bills are rolled over at the same yield and the savings APY stays constant. Rates change. This is an estimate, not advice.
Why taxes change the answer
Interest from Treasury bills is taxed by the federal government but is exempt from state and local income taxes. Savings account interest is taxed at every level. If you live in a high-tax state, a T-Bill can come out ahead even when its yield is slightly lower than your savings APY. The "APY needed to match" result shows exactly where that break-even point is for you.
About the pre-filled T-Bill yield
The Federal Reserve publishes the 3-month T-Bill rate on a discount basis, which slightly understates what you actually earn. We convert it to an approximate investment yield so it can be compared fairly with a savings APY.
Beyond the numbers
- Access: savings accounts let you withdraw any time; T-Bills pay out at maturity, though you can sell early through a brokerage.
- Safety: T-Bills are backed by the U.S. government; bank deposits are FDIC-insured up to $250,000 per depositor, per insured bank, per ownership category.
- Rate changes: a savings APY can change any day; a T-Bill locks its yield until it matures.
Learn more: What are Treasury bills? · T-Bills vs. high-yield savings
This content is for educational purposes only and isn't financial, tax or investment advice. Rates change daily; confirm current terms with your bank, broker or TreasuryDirect before making decisions. See our full disclaimer.