I Bonds vs Treasury Bills 2026: Where to Park Your Cash Safely

# I Bonds vs Treasury Bills 2026: Where to Park Your Cash Safely You've got cash sitting around. Maybe it's your emergency fund, maybe it's dry powder waiting for a market dip, maybe you just sold something and need a place to park it for 6-18 months. Your options: I Bonds and Treasury Bills. Both are backed by the US government. Both pay real yields. But they work very differently, and the right choice depends entirely on your timeline. ## Current Rates (March 2026) ### I Bonds - **Current composite rate:** 3.11% (through April 2026) - **Components:** Fixed rate (1.20%) + inflation rate (1.91% semiannual) - **Rate resets:** Every May and November based on CPI data - **Note:** The fixed rate is locked for the life of the bond. The inflation component adjusts every 6 months. ### Treasury Bills (T-Bills) - **4-week T-Bill:** ~3.55% - **3-month T-Bill:** ~3.62% - **6-month T-Bill:** ~3.70% - **1-year T-Bill:** ~3.75% With the Fed holding the federal funds rate at 3.50-3.75%, T-Bill rates are closely tracking that range. These are annualized rates, paid at maturity via the discount mechanism. ## Head-to-Head Comparison | Feature | I Bonds | Treasury Bills | |---|---|---| | Current rate | 3.11% composite | 3.55-3.75% depending on maturity | | Rate type | Variable (adjusts with inflation) | Fixed at purchase | | Minimum purchase | $25 (electronic) | $100 | | Maximum purchase | $10,000/year per person | Unlimited | | Lock-up period | 12 months minimum | None (4 weeks to 1 year maturities) | | Early withdrawal penalty | Forfeit last 3 months interest if redeemed before 5 years | Can sell on secondary market anytime | | Federal tax | Yes (can defer until redemption) | Yes (paid at maturity) | | State/local tax | Exempt | Exempt | | Inflation protection | Yes (rate adjusts with CPI) | No (fixed rate) | | Where to buy | TreasuryDirect.gov only | TreasuryDirect, any brokerage | ## The Case for T-Bills Right Now In March 2026, T-Bills are paying more than I Bonds. The 6-month T-Bill at 3.70% beats the I Bond's 3.11% composite rate by 59 basis points. And you get much better liquidity. T-Bills also have no purchase limit. If you have $100,000 to park, you can put all of it in T-Bills. With I Bonds, you're capped at $10,000 per person per calendar year ($20,000 for a married couple filing jointly, each with their own TreasuryDirect account). The real advantage: **T-Bill laddering.** Buy equal amounts of 4-week, 3-month, 6-month, and 1-year T-Bills. As each one matures, reinvest. You maintain liquidity (something matures every few weeks) while capturing the full yield curve. ### How to Buy T-Bills **Through a brokerage (easiest):** Fidelity, Schwab, and other major brokerages let you buy T-Bills at auction or on the secondary market. No fees. They show up in your regular brokerage account alongside your stocks and ETFs. **Through TreasuryDirect:** The government's website works, but the interface is stuck in 2004. It's fine for I Bonds (your only option), but for T-Bills, use your brokerage. ## The Case for I Bonds I Bonds have one feature T-Bills can't match: **inflation protection with a locked-in real return.** The current 1.20% fixed rate is yours forever. If inflation spikes to 6% again, your I Bond rate adjusts upward. Your T-Bill doesn't — it's locked at whatever rate you bought it at. I Bonds are the better choice if: - You're parking money for 1-5+ years (not just a few months) - You believe inflation could spike again (energy prices, tariffs, supply chain disruptions) - You want to defer taxes until redemption (I Bonds let you do this; T-Bill interest is taxable the year you receive it) - You haven't maxed out your $10,000 annual limit yet The I Bond is essentially an inflation insurance policy that pays you a small real return on top. In a world where CPI surprised to the upside multiple times in the last 5 years, that insurance has value. ## Tax Treatment Details Both I Bonds and T-Bills are **exempt from state and local income taxes.** If you live in a high-tax state like California (13.3%) or New York (10.9%), this is significant. A 3.70% T-Bill in California is equivalent to roughly a 4.27% CD when you account for the state tax savings. **I Bond tax deferral:** You can choose to report interest annually or defer it until you redeem the bond (or it matures in 30 years). Most people defer — why pay taxes on interest you haven't received yet? **T-Bill tax timing:** Interest is reported in the year the T-Bill matures. For a 6-month T-Bill purchased in March 2026 and maturing in September 2026, you'll report the interest on your 2026 tax return. **Education tax exclusion:** I Bond interest can be completely tax-free if used for qualified higher education expenses and you meet the income requirements. T-Bills don't get this benefit. ## Clear Recommendations by Use Case ### Emergency Fund (3-6 months expenses) **Winner: T-Bill ladder or high-yield savings account** You need immediate access. I Bonds have a 12-month lock-up. Build a T-Bill ladder where something matures every 4-8 weeks, or keep it in a high-yield savings account earning ~4%. ### Short-Term Cash (3-12 months) **Winner: T-Bills** Higher rate than I Bonds right now, full flexibility on maturity timing, no purchase limits. Match the T-Bill maturity to when you'll need the cash. ### Medium-Term Savings (1-5 years) **Winner: Both — use together** Max out your I Bond allocation ($10,000/person) for the inflation protection, then put the rest in T-Bills or short-term Treasury notes. You get inflation insurance on a portion and higher current yields on the rest. ### Long-Term Capital Preservation (5+ years) **Winner: I Bonds** The 1.20% fixed rate plus inflation adjustment means you're guaranteed a real return above inflation for up to 30 years. No other government security offers this. The $10,000 annual cap limits the size, but over 5-10 years, a couple can accumulate $100,000-$200,000 in I Bonds. ## What About Rate Decisions? The Fed's next move directly impacts T-Bill rates. If the Fed cuts rates further, T-Bill yields will drop. If inflation resurges and the Fed has to hold or hike, T-Bill yields could climb. Want to trade on rate decisions themselves? Platforms like [Kalshi](https://kalshi.com/sign-up/?referral=424cfbfe-a015-4bc0-98e1-0e2f317a119b&m=true) let you make yes/no predictions on whether the Fed will cut, hold, or raise at upcoming meetings. It's a different way to express a view on rates — not investing per se, but an interesting alternative for those who follow monetary policy closely. ## The Bottom Line **Right now, in March 2026:** T-Bills pay more and offer better liquidity. Use them for anything you might need within the next 12 months. **For longer-term safety:** Max out I Bonds at $10,000/year for the inflation protection. The fixed rate component is decent at 1.20%, and you're hedged against another inflation surprise. **The smart play:** Do both. $10,000 in I Bonds (max it every January), T-Bill ladder for everything else. You get the best of both worlds — current yield and inflation insurance. Neither of these will make you rich. That's not what they're for. They're for making sure the money you can't afford to lose doesn't lose purchasing power while you figure out what to do with it.