I Bonds vs Treasury Bonds: Which One Should You Buy?
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Key Takeaways
I Bonds currently yield 4.213% with built-in CPI inflation protection, while the 10-year Treasury yields 4.02% with no inflation adjustment.
I Bonds are capped at $10,000 per person per year; Treasuries have no purchase limit and can be sold at any time on the secondary market.
Both I Bonds and Treasuries are exempt from state and local income taxes, but I Bonds offer optional federal tax deferral until redemption.
The Fed funds rate has fallen from 4.33% to 3.64%, creating a window where I Bond fixed rates may decline on future issues — favoring buyers who act sooner.
A combined approach — maxing out I Bonds for inflation protection, then using Treasuries for liquidity and larger allocations — suits most individual investors.
With the Federal Reserve cutting rates from 4.33% in early 2025 to 3.64% as of January 2026, fixed-income investors face a shifting landscape. Two of the most popular government-backed options — Series I Savings Bonds and marketable Treasury securities — offer fundamentally different value propositions. Understanding the distinction has never been more important as inflation moderates and yields adjust.
I Bonds currently average a 4.213% composite rate, while 10-year Treasury notes yield 4.02% and 2-year notes sit at 3.42%. Both are backed by the full faith and credit of the U.S. government, but they differ sharply in liquidity, purchase limits, inflation protection, and how they fit into a broader portfolio. This guide breaks down each instrument with current data so you can make an informed allocation decision.
Whether you are building a conservative income portfolio, hedging against inflation, or simply looking for a safe place to park cash, the choice between I Bonds and Treasuries depends on your time horizon, how much you want to invest, and how you weigh inflation risk against interest rate risk.
What Are I Bonds?
What Are Treasury Bonds?
Marketable Treasury securities — including Treasury Bills (T-Bills), Treasury Notes (T-Notes), and Treasury Bonds (T-Bonds) — are the backbone of the global fixed-income market. Unlike I Bonds, these instruments trade freely on the secondary market, and their prices fluctuate with interest rate movements.
Current yields across the Treasury curve as of February 2026:
Key Differences Between I Bonds and Treasuries
Minimum holding periods
| Feature | I Bonds | Marketable Treasuries |
|---|---|---|
| Minimum hold | 1 year | None (sell anytime) |
| Early penalty | 3 months interest (before 5 years) | Market price risk only |
| Purchase cap | $10,000/year per person | No limit |
| Inflation adjustment | Yes (CPI-linked) | Only TIPS |
Which One Should You Choose?
Current Market Context: February 2026
Conclusion
I Bonds and Treasury bonds both deserve a place in the conservative investor's toolkit, but they serve different purposes. I Bonds offer unmatched inflation protection with no price risk, making them ideal for the first $10,000 of annual fixed-income savings. Marketable Treasuries provide the liquidity, scalability, and maturity flexibility that larger or more active portfolios require.
In the current environment — with the Fed at 3.64%, inflation running at 2.2%, and I Bonds yielding 4.213% — both instruments offer positive real returns. The choice is not either-or. Max out your I Bond allocation for inflation-hedged savings, then use Treasuries to fill in the rest of your fixed-income strategy based on your time horizon and income needs.
For more on building a Treasury allocation, explore our [complete Treasury guide](/treasury/) and related articles on [how to buy Treasury bonds](/treasury/how-to-buy-treasury-bonds) and [how Treasury bonds work](/treasury/how-treasury-bonds-work).
Disclaimer: This content is AI-generated for informational purposes only and does not constitute financial advice. Consult qualified professionals before making investment decisions.
Series I Savings Bonds are non-marketable securities issued by the U.S. Treasury through TreasuryDirect. Their defining feature is a composite interest rate that combines two components: a fixed rate set at issuance and a variable inflation adjustment that resets every six months based on changes in the Consumer Price Index for All Urban Consumers (CPI-U).
As of January 31, 2026, the Treasury Department reports an average I Bond rate of 4.213% for savings inflation securities. With the CPI index at 326.588 in January 2026 — up from 319.679 in February 2025, reflecting approximately 2.2% year-over-year inflation — the inflation component continues to provide meaningful yield above what pure fixed-rate instruments offer.
Key I Bond features
Purchase limit: $10,000 per individual per calendar year (electronic bonds), plus up to $5,000 in paper bonds via tax refund
Minimum holding period: 1 year — you cannot redeem I Bonds before 12 months
Early redemption penalty: If redeemed before 5 years, you forfeit the last 3 months of interest
Tax advantages: Interest is exempt from state and local income taxes; federal tax can be deferred until redemption or maturity (30 years)
Inflation protection: The variable rate adjusts with CPI, meaning your purchasing power is preserved even if inflation rises unexpectedly
I Bonds are particularly attractive for risk-averse investors who want a guaranteed real return without exposure to market price fluctuations. Because they are non-marketable, their principal value never declines — you always get back at least what you paid.
2-year Treasury note: 3.42%
10-year Treasury note: 4.02%
30-year Treasury bond: 4.67%
The Treasury Department's average rates as of January 31, 2026, show T-Bills at 3.76%, T-Notes at 3.169%, and T-Bonds at 3.369%. Treasury Inflation-Protected Securities (TIPS) yield 0.983% above inflation, offering a marketable alternative to I Bonds for inflation hedging.
Key features of marketable Treasuries
No purchase limit: You can buy as much as you want at auction or on the secondary market
Full liquidity: Sell at any time through a broker; the Treasury market is the most liquid in the world
Maturity options: T-Bills (4 weeks to 1 year), T-Notes (2 to 10 years), T-Bonds (20 to 30 years)
Price risk: If interest rates rise, the market value of your bonds declines — a real concern for longer maturities
Tax treatment: Like I Bonds, interest is exempt from state and local taxes but subject to federal income tax
For a deeper look at how these instruments function, see our guide on how Treasury bonds work. If you are ready to start buying, our step-by-step walkthrough on how to buy Treasury bonds covers both TreasuryDirect and brokerage options.
While both I Bonds and marketable Treasuries carry the full backing of the U.S. government, the differences are substantial enough to affect portfolio strategy.
Liquidity
This is the single biggest distinction. Marketable Treasuries can be sold on any business day at prevailing market prices. I Bonds are locked up for a minimum of one year and carry a three-month interest penalty if sold before five years. If you might need access to your funds on short notice, Treasuries are the clear choice.
Purchase limits
I Bonds are capped at $10,000 per person per year in electronic purchases. There is no practical limit on Treasury purchases — institutional investors routinely buy billions at auction. For investors looking to allocate $50,000 or more to government securities, I Bonds alone are insufficient.
Inflation protection
I Bonds provide built-in inflation protection through their CPI-linked variable rate. Among marketable securities, only TIPS offer comparable protection, and TIPS carry price risk that I Bonds do not. Standard T-Notes and T-Bonds pay a fixed coupon with no inflation adjustment, meaning unexpected inflation erodes your real return.
Interest rate risk
I Bonds have zero interest rate risk because they are non-marketable — their redemption value never falls below par. Marketable Treasuries, especially long-duration bonds, can lose significant market value when rates rise. A 30-year bond yielding 4.67% could lose over 15% of its market value if rates jumped by one percentage point.
Tax treatment
Both are exempt from state and local income tax. However, I Bond holders can defer federal tax until redemption, while Treasury holders owe federal tax on coupon payments in the year received. I Bonds used for qualified education expenses may be entirely tax-free — a benefit Treasuries do not offer.
The right choice depends on your investment size, time horizon, liquidity needs, and inflation outlook.
Choose I Bonds if:
You want guaranteed inflation protection without any price risk. The CPI-linked rate ensures your purchasing power is preserved, and you will never lose principal.
You are investing $10,000 or less per year and can lock the money away for at least one year (ideally five to avoid the penalty).
You want tax-deferred growth. Deferring federal tax until redemption can be valuable for long-term savers, especially those who expect to be in a lower tax bracket at redemption.
You are saving for education. The potential federal tax exclusion for qualified education expenses makes I Bonds uniquely attractive for college savings.
Choose Treasuries if:
You need liquidity. The ability to sell at any time on the secondary market is essential for investors who may need to access funds quickly.
You are allocating more than $10,000. There is no cap on Treasury purchases, making them suitable for larger portfolios and institutional investors.
You want regular income. T-Notes and T-Bonds pay semiannual coupons, providing predictable cash flow. I Bonds accrue interest but do not pay it out until redemption.
You have a view on interest rates. If you believe rates will fall further, longer-duration Treasuries could appreciate in price, offering capital gains on top of coupon income.
Consider both
For many individual investors, the optimal approach is a combination. Max out I Bonds at $10,000 per year for inflation-protected savings, then allocate additional fixed-income capital to Treasuries based on your maturity preference and income needs. A 2-year note at 3.42% provides a short-duration complement, while a 10-year at 4.02% or 30-year at 4.67% adds yield for longer time horizons.
The fixed-income environment in early 2026 reflects a Federal Reserve in easing mode. The federal funds rate stands at 3.64% as of January 2026, down meaningfully from 4.33% at the start of 2025. This rate-cutting cycle has compressed short-term yields while longer-term rates have held relatively firm, producing a normal upward-sloping yield curve — 2-year notes at 3.42% versus 30-year bonds at 4.67%.
What rate cuts mean for I Bonds
The fixed-rate component of new I Bonds is influenced by the broader rate environment. As the Fed continues to cut, the fixed rate on newly issued I Bonds could decline. However, the inflation component is driven by CPI, which is running at approximately 2.2% year-over-year (CPI index 326.588 in January 2026 versus 319.679 in February 2025). As long as inflation persists above zero, I Bonds will continue to offer a positive inflation adjustment. The current composite rate of 4.213% remains competitive with most points on the Treasury curve.
What rate cuts mean for Treasuries
Falling short-term rates have already pushed T-Bill yields down toward 3.76%. Investors who locked in longer-duration notes and bonds at higher yields during 2024 and early 2025 are sitting on gains. For new buyers, the 10-year at 4.02% still offers an attractive nominal yield, especially if inflation remains near the Fed's 2% target — implying a real yield of roughly 1.8% to 2.0%.
The bottom line on timing
With the Fed still cutting and inflation moderating, the window for locking in a competitive I Bond fixed rate may be narrowing. Meanwhile, the steepness of the yield curve rewards those willing to extend duration in marketable Treasuries. Neither product is a bad choice — the U.S. government's credit stands behind both — but understanding the tradeoffs helps you build a fixed-income allocation that matches your goals.