TIPS & Inflation-Indexed Bonds: Real Yields & Breakeven Inflation

Treasury Inflation-Protected Securities (TIPS) are government bonds designed to protect investors from inflation. Unlike traditional bonds that pay fixed nominal amounts, TIPS adjust their principal value based on changes in the Consumer Price Index, ensuring your purchasing power is preserved regardless of how prices change. Whether you’re building a retirement portfolio, hedging against inflation risk, or analyzing bond markets, understanding TIPS is essential.

What Are Treasury Inflation-Protected Securities (TIPS)?

TIPS are U.S. Treasury bonds whose principal value adjusts daily based on changes in the Consumer Price Index for All Urban Consumers (CPI-U). First issued in January 1997, TIPS guarantee a real return — your purchasing power grows at the stated coupon rate regardless of inflation.

Key Concept

TIPS pay a fixed real coupon rate on an inflation-adjusted principal. If inflation rises, your principal grows, and your coupon payments increase proportionally. At maturity, you receive at least the original par value ($1,000 face), even if cumulative deflation occurs — though secondary-market buyers may pay more than par.

The key distinction between TIPS and traditional Treasury securities is how they handle inflation:

  • Nominal bonds — pay fixed dollar amounts; inflation erodes purchasing power
  • TIPS — adjust principal for inflation; purchasing power is protected

TIPS are issued in 5-year, 10-year, and 30-year maturities and are backed by the full faith and credit of the U.S. government. For more on the broader Treasury market, see our guide to U.S. Treasury Securities.

How TIPS Work: Principal Adjustment Mechanics

The core mechanism of TIPS is the daily principal adjustment tied to CPI-U. Each day, the Treasury calculates an index ratio that determines the current inflation-adjusted principal.

Index Ratio Formula
Index Ratio = CPIsettlement / CPIissue date
The ratio of CPI on settlement date to CPI on the bond’s original issue date
Adjusted Principal
Adjusted Principal = Par Value × Index Ratio
Your $1,000 face value grows with cumulative inflation since issuance

The CPI used for TIPS calculations is the non-seasonally adjusted CPI-U with a 3-month lag. For example, principal on August 1 reflects the May CPI figure. Between monthly CPI releases, daily index ratios are calculated using linear interpolation.

Principal Adjustment Example

You purchase a TIPS bond with $1,000 face value when the reference CPI is 300.0. One year later, CPI has risen to 309.0 (3% inflation):

Metric Value
Original Principal $1,000
Index Ratio 309.0 / 300.0 = 1.030
Adjusted Principal $1,030

Your principal has grown by $30 to keep pace with inflation. If this TIPS pays a 1.5% real coupon, your next semiannual coupon is based on the $1,030 adjusted principal, not the original $1,000.

The Deflation Floor

TIPS include an important protection: at maturity, you receive the greater of the inflation-adjusted principal or the original par value. This deflation floor guarantees the original $1,000 face value is preserved if cumulative deflation occurs over the bond’s life — but it does not protect buyers who paid a premium above par on the secondary market.

Important: Deflation Floor Timing

The deflation floor applies only at maturity. Before maturity, TIPS principal, coupon payments, and market prices can all decline if deflation occurs or real yields rise. TIPS are not immune to losses before maturity.

TIPS Coupon and Yield

TIPS pay a fixed real coupon rate — typically lower than nominal Treasury yields because TIPS investors don’t require compensation for expected inflation. The coupon is applied to the inflation-adjusted principal, so actual dollar payments grow with inflation.

TIPS Coupon Payment
Coupon Payment = (Real Coupon Rate / 2) × Adjusted Principal
Semiannual coupon based on the inflation-adjusted principal

If a TIPS has a 1.5% real coupon and the adjusted principal is $1,030, the semiannual payment is (0.015 / 2) × $1,030 = $7.73. As inflation pushes the adjusted principal higher, coupon payments increase proportionally.

TIPS Total Nominal Return (Approximation)
(1 + Real Yield) × (1 + Inflation) − 1
Fisher identity relating real yield, inflation, and nominal return — assumes yields don’t change

For example, a TIPS with a 1.5% real yield held during a year of 3% inflation delivers approximately (1.015) × (1.03) − 1 = 4.55% nominal return, assuming no change in real yields. If real yields move, price gains or losses affect total return.

Breakeven Inflation Rate

The breakeven inflation rate is the inflation rate at which TIPS and comparable nominal Treasuries deliver the same return. It represents the market’s implied inflation expectation and is closely watched by economists and investors.

Exact Breakeven Formula
Breakeven = [(1 + Nominal Yield) / (1 + Real Yield)] − 1
The inflation rate where TIPS and nominal bonds have equal returns
Approximate Breakeven (Industry Practice)
Breakeven ≈ Nominal Yield − Real Yield
Simple spread approximation widely used in markets
Breakeven Calculation

A 10-year nominal Treasury yields 4.50%, and the 10-year TIPS yields 2.00% (real):

  • Exact breakeven: (1.045 / 1.02) − 1 = 2.45%
  • Approximate breakeven: 4.50% − 2.00% = 2.50%

The market implies inflation will average approximately 2.45-2.50% over the next 10 years. If actual inflation exceeds this, TIPS outperform. If inflation falls short, nominal Treasuries win.

Pro Tip

Breakeven inflation doesn’t equal expected inflation exactly. The spread reflects expected inflation, an inflation risk premium (compensation for inflation uncertainty), and a liquidity premium (TIPS are less liquid than nominal Treasuries). Decomposing these components requires model-based estimates.

For a deeper treatment of how inflation expectations are formed and measured, see our article on Inflation Expectations.

I-Bonds (Series I Savings Bonds)

I-Bonds are inflation-indexed savings bonds sold directly by the U.S. Treasury. Unlike TIPS, they are not marketable — you cannot sell them on the secondary market. I-Bonds appeal to individual investors seeking inflation protection with unique tax advantages.

I-Bond Composite Rate Formula
Composite Rate = Fixed Rate + (2 × Semiannual Inflation Rate) + (Fixed Rate × Semiannual Inflation Rate)
Combines a fixed rate set at purchase with semiannual inflation adjustments

Key I-Bond features:

  • Purchase limit: $10,000 per person per calendar year (electronic only as of January 1, 2025)
  • Tax treatment: Federal tax-deferred until redemption; exempt from state and local taxes
  • Redemption rules: 1-year lockup; redemption before 5 years forfeits 3 months of interest
  • Maturity: Earn interest for 30 years; no market price risk

I-Bonds are particularly attractive for emergency funds or education savings because of the tax deferral and guaranteed principal.

Global Inflation-Indexed Bonds

Many governments issue inflation-linked bonds similar to TIPS. The key differences are the reference inflation index and the quotation convention used in markets.

Country Bond Name Inflation Index Quotation
United States TIPS CPI-U (non-seasonally adjusted) Real-clean price
United Kingdom Index-Linked Gilts RPI (Retail Price Index) Nominal-clean price
Canada Real Return Bonds CPI (all items) Real-clean price
Australia Treasury Indexed Bonds CPI (weighted average) Real yield
France OATi / OAT€i French CPI / Eurozone HICP Real-clean price

Quotation conventions matter: U.S. TIPS are quoted on a “real-clean” basis — the price is a percentage of the inflation-adjusted principal, excluding accrued interest. UK linkers trade on a “nominal-clean” basis, so prices can exceed 200 per 100 face value after decades of RPI accumulation. Australia and New Zealand quote on a real yield basis, which is the most intuitive for comparisons.

Note: Canada discontinued new Real Return Bond issuance in 2022, though outstanding bonds continue trading.

TIPS Price Volatility Before Maturity

A common misconception is that TIPS cannot lose money. While the deflation floor protects the original par value at maturity, TIPS can experience significant price declines before maturity — just like any other bond.

TIPS prices are driven by real yields. When real yields rise, TIPS prices fall. This happened dramatically in 2022 when the Federal Reserve raised rates aggressively:

  • iShares TIPS Bond ETF (TIP) declined approximately 12% in 2022
  • Vanguard Inflation-Protected Securities Fund (VIPSX) declined approximately 12%

Even though inflation was high in 2022, TIPS funds lost money because rising real yields caused price declines that overwhelmed the inflation adjustments. This is a critical point for investors to understand: TIPS protect against inflation, not against rising interest rates.

TIPS Funds vs. Individual TIPS

A TIPS mutual fund or ETF does not have the same deflation floor as an individual TIPS held to maturity. Funds continuously buy and sell bonds at market prices, so investors bear mark-to-market risk. If you need the deflation protection, hold individual TIPS to maturity.

TIPS in Portfolio Construction

TIPS serve several roles in a diversified portfolio:

1. Inflation Hedge — TIPS directly protect against unexpected inflation, which erodes the value of nominal bonds and cash. They’re particularly valuable when inflation surprises to the upside.

2. Liability Matching — Pension funds and individuals with inflation-linked obligations (like retirement spending) can use TIPS to match real liabilities, reducing the risk that inflation will outpace their assets.

3. Real Asset Diversification — TIPS provide exposure to real (inflation-adjusted) returns without the volatility of commodities or real estate.

Pro Tip

TIPS can diversify against unexpected inflation but still behave like long-duration government bonds when real yields move. Don’t expect TIPS to be uncorrelated with other fixed income — they share interest rate sensitivity, just measured in real rather than nominal terms. For a full discussion of bond duration, see our guide.

Allocation considerations: Many financial advisors recommend allocating 10-25% of a fixed income portfolio to TIPS, increasing the allocation for investors closer to retirement or with significant inflation-sensitive expenses.

TIPS vs Nominal Treasuries

TIPS (Inflation-Protected)

  • Inflation protection: Principal adjusts with CPI-U
  • Deflation risk: Par floor at maturity; exposed before maturity
  • Yield: Real yield (typically 1-2%)
  • Tax treatment: Phantom income taxed annually (in taxable accounts)
  • Liquidity: Moderate (smaller market than nominals)
  • Best for: Inflation-worried investors, real liability matching

Nominal Treasuries

  • Inflation protection: None — fixed payments
  • Deflation risk: Benefit from deflation (fixed payments worth more)
  • Yield: Nominal yield (typically 3-5%)
  • Tax treatment: Interest taxed as received
  • Liquidity: Highest (benchmark securities)
  • Best for: Stable inflation outlook, highest liquidity needs

TIPS vs I-Bonds

TIPS (Marketable)

  • Market: Tradeable on secondary market
  • Price risk: Subject to mark-to-market losses
  • Purchase limit: None
  • Tax timing: Phantom income taxed annually (taxable accounts)
  • Liquidity: Can sell anytime at market price
  • Best for: Large allocations, institutional investors

I-Bonds (Non-Marketable)

  • Market: Not tradeable; redeem with Treasury
  • Price risk: None — always redeemed at accrued value
  • Purchase limit: $10,000/year (electronic only)
  • Tax timing: Deferred until redemption
  • Liquidity: 1-year lockup; 5-year penalty period
  • Best for: Small savers, emergency funds, education

Limitations of TIPS

CPI-U Basis Risk

TIPS protect against the official CPI-U measure, which may not match your personal inflation experience. Healthcare costs, housing in your area, and education expenses may rise faster or slower than CPI-U. TIPS hedge general inflation, not your specific cost-of-living increases.

1. Phantom Income Tax — In taxable accounts, the IRS taxes the inflation adjustment to your principal as ordinary income each year, even though you don’t receive the cash until maturity. This “phantom income” reduces the after-tax benefit of TIPS. Holding TIPS in tax-advantaged accounts (IRA, 401(k)) defers this taxation until withdrawal.

2. Lower Liquidity — The TIPS market is smaller than the nominal Treasury market. Bid-ask spreads can be wider, particularly for off-the-run issues or during market stress.

3. Real Yield Can Be Negative — In periods of strong TIPS demand or Fed quantitative easing, real yields can turn negative. A negative real yield means you’re guaranteed to lose purchasing power if you hold to maturity — you’re paying for inflation protection.

4. Duration Risk — TIPS have significant duration and will lose value when real yields rise, regardless of inflation. The 2022 TIPS selloff demonstrated this clearly.

Common Mistakes

1. Confusing Real and Nominal Yields — TIPS yields are quoted in real terms. A 2% TIPS yield plus 3% expected inflation implies roughly 5% nominal return. Don’t compare a 2% TIPS yield directly to a 5% nominal Treasury yield and conclude TIPS are worse — you’re comparing apples to oranges.

2. Ignoring Phantom Income Taxation — In taxable accounts, the inflation adjustment creates a tax bill each year without corresponding cash flow. This reduces TIPS’ after-tax advantage versus nominal bonds, especially for high-income investors in taxable accounts.

3. Assuming Breakeven Equals Expected Inflation — The breakeven rate reflects expected inflation, an inflation risk premium, and a liquidity premium. The simple spread isn’t a pure measure of inflation expectations.

4. Assuming TIPS Funds Have a Deflation Floor — Individual TIPS held to maturity guarantee at least par value. TIPS mutual funds and ETFs do not — they can and do lose money, as 2022 demonstrated.

5. Expecting TIPS to Outperform Whenever Inflation Is High — TIPS can lose value during high inflation if real yields rise faster than inflation adjustments accumulate. The relationship isn’t automatic.

Frequently Asked Questions

During deflation, TIPS principal decreases and coupon payments shrink. However, at maturity, you’re guaranteed to receive at least the original par value ($1,000 face) — the deflation floor. This floor only applies at maturity and protects par value, not any premium you may have paid. If you hold to maturity, you won’t lose principal below par to deflation. If you sell early or hold a TIPS fund, you bear deflation risk.

Yes. TIPS can lose money before maturity if real yields rise. In 2022, TIPS funds lost approximately 12% even as inflation exceeded 7%. Rising real yields caused price declines that overwhelmed inflation adjustments. Individual TIPS held to maturity have principal protection at par, but you may still lose purchasing power if you bought at a negative real yield. TIPS funds have no maturity protection and can lose money in any environment.

TIPS are subject to federal income tax but exempt from state and local taxes. In taxable accounts, “phantom income” — each year’s inflation adjustment to principal — is taxable as ordinary income, even though you don’t receive the cash until maturity or sale. This can create a tax bill without cash flow. Many investors hold TIPS in tax-advantaged accounts (IRAs, 401(k)s) where this phantom income isn’t taxed annually and instead defers until withdrawal.

Both are Treasury inflation-protected products, but they differ significantly. TIPS are marketable securities traded on bond markets with no purchase limits but subject to price fluctuations and annual phantom income taxation in taxable accounts. I-Bonds are non-marketable savings bonds with a $10,000 annual purchase limit, tax deferral until redemption, and no market price risk. TIPS suit large allocations and institutional investors; I-Bonds suit small savers wanting simplicity and tax efficiency.

It depends on your goals. Individual TIPS held to maturity provide the deflation floor guarantee (protecting par value) and known real return. TIPS funds (ETFs like TIP or VTIP) offer diversification, liquidity, and convenience but no maturity protection — you bear mark-to-market risk. If you want guaranteed inflation protection for a specific time horizon, buy individual TIPS maturing when you need the money. If you want ongoing inflation exposure with easy rebalancing, a TIPS fund may be more practical.

A negative real yield means you’re guaranteed to lose purchasing power if you hold to maturity. For example, a -1% real yield TIPS will return 1% less than inflation each year. Investors accept negative real yields when they expect high inflation and want protection, when alternatives (nominal bonds, cash) offer even worse expected real returns, or when TIPS are held for liability matching regardless of yield. Negative real yields occurred extensively from 2020-2022 during Fed quantitative easing.

Disclaimer

This article is for educational and informational purposes only and does not constitute investment advice. TIPS yields and breakeven rates cited are illustrative and change daily based on market conditions. Always conduct your own research and consult a qualified financial advisor before making investment decisions.