TIPS: Treasury Inflation Protected Securities Explained

Key Takeaways

• TIPS are Treasury securities whose principal moves with the Consumer Price Index. TreasuryDirect states it directly: the principal of a TIPS goes up with inflation and down with deflation.
• The coupon rate is fixed but the payment is not. Interest is paid every six months at a fixed rate applied to the adjusted principal, so the dollar payment rises and falls with the principal.
• There is a deflation floor at maturity. TreasuryDirect states that if the principal is equal to or lower than the original amount you get the original amount, so you never receive less than the original principal.
• The floor applies to the original principal at issue, not to what a secondary market buyer paid. Buying a seasoned TIPS that has already accumulated inflation adjustment means the floor sits well below your purchase price.
• TIPS are sold in 5, 10 and 30 year terms, with a minimum purchase of 100 dollars in 100 dollar increments, and the rate is fixed at auction and is never less than 0.125 percent.
• The number that decides whether TIPS beat a nominal Treasury is the breakeven inflation rate: the nominal yield minus the TIPS real yield. Realised inflation above it favours TIPS, below it favours the nominal bond.
• The inflation adjustment is taxed federally in the year it occurs even though the cash arrives at maturity. TreasuryDirect states that federal tax is due each year on interest earned and that any increase or decrease in principal during the year may affect your federal taxes. There is no state or local tax.

What Are TIPS and What Do They Actually Protect?

Treasury Inflation Protected Securities are U.S. Treasury bonds with one structural change: the principal is indexed to consumer prices. TreasuryDirect describes the adjustment mechanism plainly, saying the principal of a TIPS goes up with inflation and down with deflation, using a version of the Consumer Price Index published by the Bureau of Labor Statistics.

Understanding what that protects requires separating two things that ordinary bond investing usually lets you blur together. A conventional Treasury promises a fixed number of dollars. Whether those dollars buy what you expect them to buy depends on inflation over the holding period, and that risk sits entirely with the holder. A TIPS moves the dollar amount so that its purchasing power is preserved. The protection is against unexpected inflation specifically, because expected inflation is already reflected in the yield of the conventional bond.

That distinction is the single most useful idea on this page. TIPS do not pay off because inflation is high. They pay off relative to a nominal Treasury when inflation turns out higher than the market expected when you bought. If inflation runs at exactly the rate the market priced in, both securities deliver roughly the same result and the TIPS holder has simply paid for insurance that was not needed. If inflation runs below expectations, the TIPS holder does worse than the nominal holder.

The basic terms are set out by TreasuryDirect: TIPS are sold for a term of 5, 10 or 30 years, with a minimum purchase of 100 dollars in increments of 100 dollars. The rate is fixed at auction and is never less than 0.125 percent, and TIPS auction rules allow for negative real yield bids. TIPS are also eligible for STRIPS.

The general terms of every marketable Treasury security, including bills, notes, bonds and floating rate notes, are covered at treasury securities. This page covers only what is specific to the inflation-linked structure.

How Does the Inflation Adjustment Work?

Three moving parts, and only one of them is fixed.

1. The principal is indexed. The par value is multiplied by an index ratio derived from the Consumer Price Index. Inflation raises it, deflation lowers it.
2. The coupon rate is fixed, but the payment floats. TreasuryDirect states that TIPS pay a fixed rate of interest every six months until they mature, and that because interest is paid on the adjusted principal, the amount of the interest payment also varies. A fixed percentage of a moving base produces a moving payment.
3. The maturity payment carries a floor. TreasuryDirect states that when a TIPS matures, if the principal is higher than the original amount you get the increased amount, and if the principal is equal to or lower than the original amount you get the original amount.

Work an example through to see how the pieces interact. The figures below are hypothetical and simplified to annual compounding and annual interest so the arithmetic is checkable at a glance. Real TIPS pay semiannually and use an indexation lag, so an actual security’s numbers differ in detail while behaving the same way.

Assume 10,000 dollars of a five year TIPS with a 2.00 percent real coupon, and assume inflation runs at 3 percent every year.

Total interest across the five years is 1,093.68 dollars, and the principal repaid at maturity is 11,592.74 dollars, for a total of 12,686.42 dollars on a 10,000 dollar investment. Notice that the coupon rate never changed. Every dollar of the increase in the payment came from the principal moving underneath it.

Now run the same security through five years of 1 percent annual deflation.

Total interest is 970.40 dollars. The adjusted principal at maturity is 9,509.90 dollars, which is below the original 10,000 dollars, so the floor applies and the holder receives 10,000 dollars. Total received is 10,970.40 dollars.

The floor did real work there, returning 490.10 dollars that the index ratio alone would have taken away. But notice what it did not do: the interest payments were still calculated on the deflated principal, and no floor applied to them. Deflation protection at maturity is not the same as deflation protection throughout.

What Is the Breakeven Inflation Rate?

The breakeven is the arithmetic that turns "should I buy TIPS or a regular Treasury?" from a forecast into a comparison. It is a subtraction:

Breakeven inflation rate = nominal Treasury yield − TIPS real yield, for securities of the same maturity.

Suppose, hypothetically, a ten year nominal Treasury yields 4.30 percent and a ten year TIPS carries a real yield of 1.80 percent. The breakeven is 2.50 percent. That number is the market’s implied inflation expectation over the next ten years, and it is also the hurdle:

• If inflation over the ten years averages more than 2.50 percent, the TIPS delivers more than the nominal bond.
• If it averages less than 2.50 percent, the nominal bond delivers more.
• If it averages exactly 2.50 percent, the two produce roughly the same result and the choice did not matter.

Return to the worked example above to see the rule confirmed. A five year nominal Treasury yielding 4.50 percent against a five year TIPS with a 2.00 percent real yield gives a breakeven of 2.50 percent. In the 3 percent inflation scenario, realised inflation was above the breakeven, and the TIPS produced 12,686.42 dollars against 12,250.00 dollars for the nominal bond (5 payments of 450 dollars plus 10,000 dollars of principal). In the deflation scenario, realised inflation was far below the breakeven, and the nominal bond produced 12,250.00 dollars against 10,970.40 dollars for the TIPS. The breakeven predicted the direction of both results.

Three things about the breakeven are worth internalising, because they are the source of most confusion about TIPS.

First, buying TIPS is not a bet that inflation will be high. It is a bet that inflation will be higher than the breakeven. In a period when the market already expects high inflation, the breakeven is wide and TIPS are correspondingly expensive.

Second, the breakeven is not a forecast you have to beat by being clever. Many investors buy TIPS specifically because they do not want to take a view. Accepting the breakeven and holding a real yield to maturity removes inflation from the outcome entirely, which is a legitimate goal for money earmarked for future spending.

Third, the breakeven includes more than expected inflation. It also embeds compensation for inflation uncertainty and for the relative liquidity of the two markets. Treating it as a pure forecast overstates its precision. The macro context for how real yields and breakevens move is covered at real yields and breakevens.

What Can Still Go Wrong With TIPS?

Inflation protection is not general protection, and the gap between the two is where TIPS holders get surprised.

1. Interest rate risk is fully present. TIPS have a real yield, and real yields move. When real yields rise, TIPS prices fall, exactly as nominal bond prices fall when nominal yields rise. A thirty year TIPS is a long duration instrument and can lose substantial market value in a rising real yield environment while doing precisely what it was designed to do. The SEC makes the general version of this point about government securities: the guarantee covers the payments, not the market price if you sell before maturity.
2. The deflation floor protects the original principal, not your purchase price. A TIPS bought in the secondary market after years of inflation carries an adjusted principal well above its original par. The floor still sits at the original amount. A buyer who paid for that accumulated adjustment can lose more of it to deflation than the phrase "you never get less than the original principal" suggests, because the original principal is the Treasury’s figure from issue, not the investor’s cost.
3. The index may not match your inflation. The adjustment follows a national consumer price index. Your own cost increases depend on housing, healthcare, education and location in proportions the national basket does not share. The protection is against a published statistic, and that statistic is a reasonable proxy rather than a personal one.
4. Taxation of the inflation adjustment is a cash flow problem. TreasuryDirect states that federal tax is due each year on interest earned and that any increase or decrease in the principal during the year may affect your federal taxes. In a high inflation year, the principal increase can generate a federal tax liability larger than the cash interest actually received. There is no state or local tax. This is the origin of the term phantom income, and it is why TIPS are frequently held in tax-advantaged accounts. Confirm your own treatment against bond and fixed income taxation and a tax professional.
5. The indexation lag exists. The index used to adjust principal reflects prices from a period before the payment date. In stable conditions this is immaterial. During a sharp turn in inflation it means the adjustment arrives slightly behind the reality it is tracking.
6. Liquidity is good but not identical to nominal Treasuries. The TIPS market is smaller than the nominal Treasury market, and in stressed conditions the difference can widen, which is one reason a breakeven can move for reasons unrelated to inflation expectations.

Who Are TIPS Actually For?

TIPS suit a specific job, and the clearest way to describe it is by what the money is for rather than by an investor type.

There is one more comparison worth making explicitly, because it is the most common real-world alternative. Series I savings bonds also adjust for inflation, using a different mechanism: a fixed rate combined with a semiannual inflation rate, with tax deferred until redemption and an annual purchase limit. TIPS have no purchase limit, are freely tradable, and are taxed as the adjustment accrues. The two are complements more than substitutes, and Series I and EE savings bonds covers the other side of that comparison in full.

How Do You Buy TIPS?

There are three routes, and they are not interchangeable.

• At auction, directly. TreasuryDirect sells TIPS in 5, 10 and 30 year terms with a 100 dollar minimum and 100 dollar increments. A non-competitive bid accepts the rate set at the auction, which is how individual investors normally participate. This route gives you a specific security with a specific maturity date and no ongoing fee.
• In the secondary market, through a broker. This gives access to seasoned TIPS with maturities that do not match the current auction calendar, which matters if you are matching a specific future date. It also means paying for whatever inflation adjustment has already accumulated, with the consequences for the deflation floor described above.
• Through a fund. A TIPS mutual fund or ETF holds a rotating portfolio, so it has no maturity date of its own and never returns a known real amount on a known date. It buys diversification across maturities and easy trading. It gives up the single feature that makes an individual TIPS useful for a dated liability.

That last trade-off is the one people get wrong most often. If the reason for holding TIPS is to fund a known future expense in real terms, an individual TIPS maturing near that date does the job and a fund does not, because the fund’s value on your date depends on where real yields sit that month. If the reason is a general inflation hedge inside a diversified portfolio, the fund is simpler and the maturity date is irrelevant.

One structural note for the direct route: TreasuryDirect states that TIPS are eligible for STRIPS, meaning the interest and principal components can be separated and traded individually. That is primarily an institutional mechanism, but it is why zero-coupon inflation-linked instruments exist at all.

Common Mistakes and Misconceptions

• Believing TIPS cannot lose money. They can lose substantial market value when real yields rise. The inflation adjustment and the deflation floor say nothing about the price between issue and maturity.
• Buying TIPS because inflation is high. High current inflation is already in the breakeven. The relevant question is whether future inflation exceeds it, not whether recent inflation was uncomfortable.
• Assuming the deflation floor protects a secondary market purchase. The floor is set at the original principal from issue. A seasoned TIPS bought at an adjusted principal well above par has a floor well below its cost.
• Overlooking the annual tax on the principal adjustment. Federal tax is due each year on interest earned, and a principal increase can affect that year’s federal taxes, potentially exceeding the cash actually received. There is no state or local tax.
• Treating a TIPS fund as a dated inflation-protected asset. A fund has no maturity date. If the goal is a known real amount on a known date, only an individual TIPS delivers it.
• Expecting the index to track personal costs. The adjustment follows a national consumer price index, not your own basket of housing, healthcare and education.
• Comparing a TIPS yield directly against a nominal yield. One is a real yield and the other is nominal. The comparison only means something after computing the breakeven.
• Using TIPS as an emergency fund. Market value fluctuates, and money that may be needed at short notice belongs in cash equivalents.

Putting It Together

TIPS solve one problem precisely and leave every other bond risk untouched. That combination is the source of both their usefulness and the disappointment they sometimes cause. An investor who buys TIPS expecting an asset that cannot fall has misread the product. An investor who buys them to remove inflation from a long-dated spending goal has read it exactly right.

You should now be able to work through a TIPS decision without guessing. Start with the breakeven: subtract the TIPS real yield from the nominal Treasury yield at the same maturity, and recognise that this is the hurdle rate, not a forecast you need to beat. Decide whether you want to take a view on inflation or remove it from the outcome, because those lead to different answers. Match the maturity to the date the money is needed if there is one, which means an individual security rather than a fund. Check where the security will be held, because the annual federal tax on the principal adjustment can exceed the cash interest in a high inflation year. And if you are buying in the secondary market, look at how much inflation adjustment has already accumulated, because that is the distance between your cost and the deflation floor.

The most expensive misunderstanding is the one about safety. TIPS carry the full faith and credit of the U.S. government on their payments, and that guarantee says nothing about their market price. A thirty year TIPS is a long duration instrument. A rise in real yields will mark it down hard, and it will still be doing its job, because its job is to deliver a known real amount at maturity rather than a stable price along the way. Anyone who cannot hold to maturity through that has bought the right instrument for the wrong horizon.

Where to go next depends on what remains unclear. If the price behaviour is the concern, bond duration explained quantifies how far a long bond moves when yields do. If the comparison against other Treasury securities is the question, treasury securities covers bills, notes, bonds and floating rate notes. And if the practical alternative you are weighing is savings bonds rather than a nominal Treasury, Series I and EE savings bonds sets out that comparison directly.

Frequently Asked Questions

References

This guide is based on U.S. government and regulator publications, each retrieved and verified on 22 August 2026:

• TreasuryDirect: Treasury Inflation Protected Securities (TIPS): the 5, 10 and 30 year terms, the 100 dollar minimum and increment, the statement that principal goes up with inflation and down with deflation, the maturity rule that you never get less than the original principal, semiannual interest paid at a fixed rate on the adjusted principal, the rate being fixed at auction and never less than 0.125 percent, and the federal-tax-each-year, no-state-or-local-tax treatment.
• TreasuryDirect: Understanding Pricing and Interest Rates: how auction results translate into the price and yield an investor actually receives on a Treasury marketable security.
• Investor.gov: Bonds: the general framing of a bond as a lending relationship with contractual interest and principal payments.
• SEC Office of Investor Education and Advocacy: Investor Bulletin, Fixed Income Investments, When Interest Rates Go Up, Prices of Fixed-Rate Bonds Fall: the point that a federal guarantee covers the payments and not the market price if you sell before maturity, and the maturity and coupon effects on interest rate sensitivity.
• FINRA: Bonds: the bond taxonomy including inflation-linked government securities, and duration as a measure of price sensitivity to yield changes.

The inflation and deflation tables and the breakeven illustrations are original, hypothetical calculations from the stated assumptions, simplified to annual compounding and annual interest so the arithmetic is checkable. Real TIPS pay semiannually and apply an indexation lag. The yields used are round numbers chosen for clarity, not observed market levels, and nothing here is a projection or a recommendation. This is educational content, not personalised investment, tax, or legal advice.