The Short Answer
In April 2026, with 12-month Treasury yields around 4.40% and the best 12-month CD rates sitting at roughly 4.70%, the CD looks better at first glance — but if you live in California, New York, or New Jersey, the T-bill almost always wins after state tax. For IRA-held savings, CDs usually edge out. This guide shows you how to do the math in 90 seconds for your specific situation.
How Each Product Actually Works
Certificates of Deposit (CDs)
You lock a deposit with a bank for a set term (3, 6, 12, 24, or 60 months) in exchange for a fixed APY. Federally insured up to $250,000 per depositor, per bank, per ownership category through the FDIC. Pulling funds early usually costs 3–12 months of interest, depending on term and bank.
U.S. Treasury Bills
Short-term U.S. government debt sold at a discount. Terms of 4, 8, 13, 17, 26, and 52 weeks are auctioned weekly/monthly on TreasuryDirect or through brokerages. Backed by the full faith and credit of the U.S. government — zero state and local income tax on the interest, which is the hidden advantage most savers miss.
High-Yield Savings (HYSA) for Reference
Fully liquid, typically 4.00–4.50% APY in April 2026 from online banks. FDIC-insured. Rates are variable and can drop any day.
Side-by-Side Rate Comparison (April 2026)
| Product | Yield (APY/yield) | Liquidity | Insurance | Taxability |
|---|---|---|---|---|
| 12-month CD (top banks) | 4.70% | Locked (penalty) | FDIC $250k | Federal + state |
| 13-week T-bill | 4.28% | Sell anytime on market | U.S. government | Federal only |
| 52-week T-bill | 4.40% | Sell anytime on market | U.S. government | Federal only |
| High-yield savings | 4.25% (variable) | Fully liquid | FDIC $250k | Federal + state |
| I-Bonds | 3.11% (fixed+variable) | 1-year lockup | U.S. government | Federal only, deferred |
| Money market funds | 4.35% (7-day SEC yield) | Usually same-day | SIPC at broker | Federal + state (most) |
After-Tax Math — A $10,000 Example
Saver A: Texas (no state tax)
- 12-month CD at 4.70% → $470 interest. Federal tax at 22% bracket → net $366.
- 52-week T-bill at 4.40% → $440 interest. Federal only 22% → net $343.
Winner: CD by $23. State-tax-free T-bill advantage doesn’t apply here.
Saver B: California (13.3% top state bracket; 9.3% for most middle earners)
- 12-month CD at 4.70% → $470. Federal 22% + state 9.3% = 31.3% effective → net $323.
- 52-week T-bill at 4.40% → $440. Federal 22% only → net $343.
Winner: T-bill by $20.
Saver C: New York City, high earner
- 12-month CD at 4.70% → $470. Combined federal + state + city ≈ 42% → net $273.
- 52-week T-bill at 4.40% → $440. Federal 32% → net $299.
Winner: T-bill by $26, and the spread widens with higher balances.
Early-Withdrawal Risk
CDs punish early access; T-bills don’t. If you sell a T-bill on the secondary market before maturity, you may get slightly more or less than face value depending on where rates moved — but you won’t pay a fixed penalty. For emergency-fund-adjacent money, T-bills are almost always the better choice.
| Scenario | CD Penalty | T-bill Penalty |
|---|---|---|
| Need cash in month 4 of 12-month | 3 months’ interest lost | Tiny mark-to-market gain/loss |
| Rates rise 100bp after purchase | You’re stuck at old rate | You can sell and reinvest |
| Rates fall 100bp after purchase | You win — locked in high rate | You win — your T-bill is now worth slightly more |
When a CD Still Makes Sense
- Inside a Roth IRA or Traditional IRA. Interest is shielded from taxes anyway, so the T-bill’s state-tax advantage disappears. CDs usually pay 20–40 bps more.
- You’re sure you won’t touch the money for 2+ years and want to lock in today’s rates against future cuts. Long-term CDs currently pay 4.95% for 60-month terms at top credit unions.
- You’re using a CD ladder (rungs at 3, 6, 12, 18, 24 months) for a smoother rate blend.
When T-Bills Clearly Win
- You live in a high-state-tax state (CA, NY, NJ, OR, MN, HI, MD).
- You want optionality in case the Fed cuts or raises rates sharply.
- Your balance is above $250k per bank (T-bills have no FDIC cap).
- You’re holding emergency-fund money that might need to be deployed in 2–6 months.
Where to Buy Each
- CDs: Marcus, Ally, Bread Savings, Synchrony, Raisin aggregator, plus local credit unions. Shop around — 75 bps spread between banks is common.
- T-bills: TreasuryDirect.gov (no fees) or through Fidelity / Schwab / Vanguard / E*TRADE. Brokerage auctions are often easier to manage but may skip a week to match Treasury auction calendars.
Amazon Picks
- “The Only Investment Guide You’ll Ever Need” (Andrew Tobias) — classic guide to fixed income basics
- “I Will Teach You to Be Rich” (Ramit Sethi) — modern take on automating savings
Final Takeaway
Don’t obsess over the 30 bps headline rate. Tax treatment, liquidity needs, and insurance coverage determine the real winner for your balance. For a $10,000 decision, the difference after tax and penalties can easily swing by $100–$300 per year, which is meaningful over a decade of compounding.
This is general educational content, not personalized investment advice. Consult a tax professional or fiduciary advisor for your own situation.
Sources
- U.S. Treasury Department, TreasuryDirect current yields (April 2026)
- FDIC National Rates and Rate Caps, April 2026
- DepositAccounts.com CD survey (April 2026)
- IRS Publication 550, Investment Income and Expenses (2025)
- Tax Foundation State Individual Income Tax Rates 2026