Bond Yield to Maturity vs Actual Return: Coupons, Reinvestment and Early Sales

A bond quoted at a 7.22% yield to maturity does not promise to add 7.22% to your spendable balance every year. Yield to maturity, or YTM, is the discount rate that makes the bond's promised payments worth its purchase price. Your eventual cash outcome also depends on when you sell, what you do with coupons and whether the issuer pays as promised.

The crucial distinction is between the internal rate of return on dated cash flows and the compound growth of wealth at a chosen horizon. Both can be valid measures. They answer different questions.

One bond, three different yield measures

Consider a hypothetical noncallable bond with a face value of 100, an annual coupon of 5 and exactly two years remaining. Buy it just after a coupon date for 96. There is no accrued interest. The scheduled receipts are 5 in one year and 105 in two years. Ignore fees, tax, currency movements and default for now.

The coupon rate is 5/100, or 5%. Current yield is 5/96, approximately 5.21%. Current yield describes income relative to price, but leaves out the gain from receiving 100 of principal after paying 96. YTM incorporates that difference and the timing of both payments:

96 = 5/(1 + y) + 105/(1 + y)².

Solving gives y of approximately 7.2191%. Simply adding half the four-point discount to each year's coupon and dividing by 96 is not equivalent: money received in year two is not available in year one. YTM is the promised cash flows' internal rate of return, not the proportion of the purchase price paid out as annual income.

Reinvestment changes terminal wealth, not the definition of IRR

Leave the first coupon in a non-interest-bearing account. At the end of year two, principal and both coupons total 110. The annualized growth of that wealth is √(110/96) − 1, or 7.0436%. The issuer has not shortchanged you. The first coupon simply earned nothing after it arrived.

A common explanation goes too far by saying YTM cannot be calculated unless coupons are reinvested. The IRR calculation itself requires no actual reinvestment. If the dated receipts are 5 and 105 as promised, their IRR remains 7.2191%. Reinvestment at that rate is what allows the growth from 96 to terminal wealth to match it as well.

Spending the first coupon does not erase the income. But you cannot count it both as spending power already enjoyed and as money still compounding in the account. Decide whether the question is investment cash-flow performance or the amount available to fund a future liability.

Selling early introduces a new market price

Suppose you sell immediately after receiving the first annual coupon. The buyer will receive only 105 a year later. At a market yield of 10%, its theoretical price is 105/1.10 = 95.4545. Your one-year total return is (5 + 95.4545)/96 − 1, approximately 4.6402%.

If the market yield instead falls to 4%, the price becomes 105/1.04 = 100.9615 and the one-year return is approximately 10.3766%. The coupon has not changed. The sale price has. These are model values, not executable quotes; spreads and market depth can reduce the cash actually received.

A two-year YTM is therefore not a one-year spending forecast. For small changes in yields, duration and DV01 calculations can help translate price sensitivity into money. Large moves, changing credit spreads or embedded options require more careful repricing rather than blind extrapolation.

A call provision can move the finish line

Now take a separate bond bought at 103, paying 5 annually on a face value of 100, with two years to maturity. The issuer may call it for 100 at the first year's coupon date. The scheduled two-year YTM is about 3.4226%. If called after one year, the payment is 105 and the return is only 105/103 − 1 = 1.9417%.

The premium is lost sooner than a maturity-only comparison suggests. Check every applicable call date and price, not just the final maturity date. Yield to worst is a contractual-scenario comparison, generally identifying the lowest relevant yield under permitted redemption outcomes. It is not a floor under default losses or the price available in a forced sale.

Use the actual cash price and a consistent convention

A quoted clean price may exclude accrued interest owed to the seller. The settlement amount can therefore exceed the headline quote, before commissions. Our example deliberately starts just after a coupon payment so that 96 is the cash outlay. Using a clean price as the full investment while counting the next whole coupon as newly earned income can overstate the result.

Annual and semiannual payment conventions also need to be reconciled: a nominal annual yield is not automatically an effective annual rate. Compare like-for-like day counts, payment frequency, tax treatment and currency. A higher promised yield may compensate for poorer payment prospects, rather than represent a superior achievable return.

A bond fund's portfolio YTM is not a fixed return promised to shareholders either. Holdings change, expenses reduce results and the fund does not necessarily mature alongside any one security. Separate a single bond's scheduled cash flows from an ongoing portfolio's evolving net asset value.

A practical cash-flow check before comparing bonds

1. Record the full initial outlay, including accrued interest and transaction charges, in one currency.
2. List each coupon, principal repayment and relevant call scenario with its date and amount.
3. Choose the holding horizon and specify whether coupons will be spent, held as cash or reinvested at an explicit rate.
4. For an early sale, test higher and lower exit yields, executable spreads and costs; assess credit repayment separately.
5. Report the cash-flow IRR and terminal-wealth growth separately, and check that no coupon has been counted twice.

YTM is a useful price-to-cash-flow yardstick. Turning it into a personal funding plan requires one more step: matching the bond's dates, reinvestment assumptions and possible exit values to the date when the money is actually needed.