Should I Own Nominal Treasuries or TIPS?
Both nominal Treasuries and TIPS (Treasury Inflation-Protected Securities) are debt obligations of the U.S. government, and both carry very low credit risk as a result. Where they diverge is in how they respond to inflation, and that divergence changes their tax treatment, their yield behavior, and the role each may play in a portfolio.
This is not a question with a universal answer. It depends on where inflation risk already sits in an investor's broader plan, what account the bonds will be held in, and the time horizon involved. This article walks through the mechanics of each, then the tradeoffs that typically matter most for a retirement-focused portfolio.
What Is a Nominal Treasury?
A nominal Treasury is the "plain" version most investors picture when they think of government bonds: Treasury bills, notes, and bonds issued at a fixed face value, paying a fixed coupon rate (for notes and bonds) until maturity, at which point the original principal is returned.
Key characteristics:
- Notes and bonds pay a fixed coupon, known in advance, for the life of the security; bills pay no coupon and are generally issued at a discount, maturing at face value
- Principal returned at maturity is the original face value, unadjusted
- Interest is subject to federal income tax but generally exempt from California and other state income taxes
- Available across a wide range of maturities, from a few weeks to 30 years
How inflation affects a nominal Treasury: Inflation is not built into the bond's cash flows. If inflation rises unexpectedly after purchase, the fixed coupon and fixed principal buy less than they would have in a lower-inflation environment. The bond's real (inflation-adjusted) return declines even though its nominal return is unchanged. This erosion of purchasing power is the central risk nominal bondholders take on.
What Is a TIPS Bond?
TIPS are Treasury securities whose principal value is adjusted periodically based on changes in the Consumer Price Index (CPI). As the CPI rises, a TIPS bond's principal is adjusted upward; if the CPI falls, the principal can adjust downward. At maturity, however, Treasury generally pays the greater of the inflation-adjusted principal or the original par amount, so cumulative deflation over the life of the bond generally cannot reduce what is repaid below the original face value. This floor applies at maturity; it does not protect the bond's market price from falling below par before then.
Key characteristics:
- Principal adjusts with CPI, providing protection against changes in the CPI measure of inflation
- Coupon rate is fixed, but because it applies to an adjusting principal, the actual dollar amount of each coupon payment can rise or fall with inflation
- Includes a deflation floor at maturity: Treasury generally pays the greater of the inflation-adjusted principal or the original par amount, even if cumulative CPI adjustments were negative
- Interest and principal adjustments are subject to federal income tax but generally exempt from California and other state income taxes
How inflation affects a TIPS bond: Because the principal itself moves with CPI, a TIPS bond's cash flows are designed to keep pace with realized inflation over the holding period. This does not mean TIPS are risk-free. They still carry interest-rate risk (their market price can decline if real yields rise) and the inflation adjustment tracks CPI specifically, which may not perfectly match an individual investor's personal cost-of-living increases.
How Do Nominal Treasuries and TIPS Compare?
| Feature | Nominal Treasuries | TIPS |
|---|---|---|
| Coupon | Fixed dollar amount | Fixed rate applied to an adjusting principal |
| Principal at maturity | Original face value | Greater of inflation-adjusted principal or original par amount |
| Inflation protection | None built in | Principal adjusts with CPI |
| Interest-rate risk | Yes | Yes (tied to real yields rather than nominal yields) |
| Federal tax treatment | Coupon interest taxed annually | Coupon interest and annual inflation adjustment both generally taxed annually |
| California state tax | Generally exempt | Generally exempt |
| Account considerations | Can be held in taxable or tax-advantaged accounts, depending on the overall plan | Tax treatment of inflation adjustments can be an important consideration in taxable accounts |
(as of the original publication date)
What Is the Breakeven Inflation Rate, and Should I Use It to Decide?
The breakeven inflation rate is the yield difference between a nominal Treasury and a TIPS bond of the same maturity. If a 10-year nominal Treasury yields more than a 10-year TIPS by a certain margin, that difference is approximately the average annual inflation rate at which the two securities would have similar returns, subject to differences in pricing, liquidity, and other factors.
How it can be used: Some investors and advisors reference the breakeven rate as a rough gauge of what the bond market is pricing in for future inflation. If an investor believes realized inflation will run meaningfully above the current breakeven rate, TIPS may appear more attractive on a relative basis. If an investor believes inflation will run below the breakeven rate, nominal Treasuries may appear more attractive.
Why it is not a precise forecast: The breakeven rate also reflects factors beyond a pure inflation forecast, including relative liquidity between the two markets and an inflation risk premium that investors may demand for uncertainty. It should be treated as one data point among several, not a guarantee of what inflation will actually do.
Should I Worry About the Tax Treatment of TIPS?
This is one of the most commonly overlooked differences between the two security types, and it can meaningfully affect after-tax returns depending on where the bonds are held.
The phantom income issue: When a TIPS bond's principal is adjusted upward for inflation, that adjustment is generally treated as taxable income in the year it occurs, even though the investor does not receive the cash from that adjustment until the bond matures or is sold. This means a TIPS holder in a taxable account may owe tax on income they have not yet received in cash, a mismatch sometimes called phantom income.
Why this matters for account placement: Because of the potential mismatch between taxable income and cash received, investors may consider the tax consequences of holding TIPS in a taxable account as part of their broader asset-location decisions. Tax-deferred accounts (such as a traditional IRA or 401(k)) or tax-advantaged accounts (such as a Roth IRA) can avoid current federal taxation of the annual inflation adjustment, although the appropriate account location depends on the investor's broader tax and financial circumstances. Nominal Treasuries can also be held across different account types, with the relative tax consequences depending on the investor's circumstances and overall asset-location strategy; their coupon is the only annual taxable item, and it is paid in cash. The appropriate placement across account types depends on an investor's full tax situation, other holdings, and overall asset-location strategy. For a broader framework on placing different asset types across account types, see the related discussion in the tax-efficient asset location post.
California treatment: Both nominal Treasury interest and TIPS interest, including the inflation adjustment, are generally exempt from California state income tax, even though both remain subject to federal income tax. The state exemption does not resolve the federal phantom income timing issue for TIPS held in a taxable account.
How the Characteristics of Each May Fit Into a Retirement Portfolio
Nominal Treasuries can provide:
- Predictable, fixed nominal cash flows for the life of the security
- Simpler annual tax reporting, since the coupon is the only taxable item and it is paid in cash
- No direct adjustment for inflation; the real return depends on how CPI moves relative to the yield locked in at purchase
TIPS can provide:
- Principal adjustments linked to CPI, which can provide protection against unexpected increases in the CPI measure of inflation over the holding period
- A coupon payment that moves with the adjusting principal
- An annual inflation adjustment that is generally taxable when accrued in a taxable account, a factor relevant to account placement
Context worth noting: The broader retirement plan already includes inflation-linked income sources in many cases, such as Social Security benefits with annual cost-of-living adjustments.
A blended approach: Nominal Treasuries and TIPS can also be combined within a fixed-income allocation, with the mix reflecting the portfolio's objectives, inflation exposure, tax considerations, and time horizon.
Common Mistakes When Comparing Nominal Treasuries and TIPS
Mistake 1: Treating the breakeven rate as a certainty.
Risk: Assuming the market's implied inflation expectation will be exactly right, then being surprised when realized inflation differs.
Approach: Use the breakeven rate as one input among several, not a forecast to bet the full allocation on.
Mistake 2: Holding TIPS in a taxable account without accounting for phantom income.
Risk: An unexpected tax bill on inflation adjustments that have not yet been received in cash.
Approach: Evaluate the federal tax consequences of TIPS in taxable and tax-advantaged accounts as part of the overall asset-location strategy.
Mistake 3: Assuming TIPS eliminate all inflation risk.
Risk: Believing a TIPS allocation fully insulates a portfolio from inflation's effects.
Approach: Recognize that TIPS track CPI, which may not match an individual investor's personal spending patterns, and that TIPS still carry interest-rate and liquidity risk.
Mistake 4: Ignoring inflation protection already present elsewhere in the plan.
Risk: Over-allocating to TIPS without accounting for other inflation-linked income, such as Social Security's cost-of-living adjustments.
Approach: Consider the plan holistically before sizing a TIPS allocation.
Deeper Dives: Related Topics
For related fixed income strategy, explore:
→ Related strategyFixed Income in Retirement → → Related strategyTax-Efficient Asset Location →The Bottom Line
Nominal Treasuries and TIPS both come from the same issuer and carry very low credit risk, but they solve different problems. Nominal Treasuries offer fixed, predictable cash flows; TIPS offer principal that is designed to move with realized inflation, at the cost of more complex tax treatment when held outside a tax-deferred account.
Neither is a default "correct" choice. The appropriate mix depends on an investor's existing inflation exposure, tax situation, account structure, and time horizon, and those variables interact in ways that are easy to underweight when looking at either security in isolation.