The Coupon Bias Trap

Chasing the highest coupon is like shopping only on price; you ignore quality, duration, and credit risk.

Key takeaways

• High coupons attract income-seeking investors but often signal higher credit risk
• A 7% coupon from a BB-rated issuer is not comparable to a 4% coupon from an AAA issuer — they're offering different risk/reward trade-offs
• The market prices all available information: if a bond yields much higher, there's usually a reason
• Comparing bonds requires adjusting for credit quality, maturity, and liquidity, not just coupon size
• Income is important, but not at the cost of losing principal to default

The income seeker's dilemma

Retirees and income investors often focus on coupon payments because they plan to spend the income. A 6% coupon sounds better than a 3% coupon. But a 6% coupon is often attached to a higher-risk bond, and higher risk means a higher probability of losing principal.

Example: In 2020–2022, many retirees abandoned Treasury bonds (yielding 1–2%) and flocked to high-yield corporate bonds and emerging-market bonds offering 6–8% coupons. They reasoned, "If I'm earning 6%, I can live on $60,000 from a $1 million portfolio instead of only $20,000."

But a substantial portion of those high-coupon bonds defaulted or declined sharply as credit tightened in late 2023. Those retirees lost both income and principal, ending up worse off than if they'd held boring 3% Treasury bonds.

The math: comparing unequal bonds

Consider two bonds, both maturing in 5 years:

Bond A: AAA Corporate

• Coupon: 3.5%
• Yield: 3.5%
• Price: par ($1,000)
• Default probability: near zero

Bond B: BB Junk

• Coupon: 7.0%
• Yield: 7.0%
• Price: par ($1,000)
• Default probability: ~5% over 5 years

Both are $1,000 investments. Over 5 years, Bond A pays $175 in coupons ($35 × 5). Bond B pays $350 in coupons ($70 × 5).

But Bond B has a 5% chance of paying nothing if the issuer defaults. The expected value of Bond B's cash flows is:

(95% × $1,350) + (5% × $0) = $1,282.50 expected value for a $1,000 investment.

Bond A's expected value is nearly $1,175 ($35 × 5 + $1,000 principal).

The gap narrows when you account for risk. Bond B looks worse when you price in the default risk.

More importantly: would you rather have a sure $175 in income (Bond A) or a risky $350 in income (Bond B, net of expected default losses)?

Why high-coupon bonds are high-coupon bonds

The market is efficient in pricing risk. A bond that yields much higher than similar-maturity Treasuries does so because the market prices in the extra risk.

Reasons a bond might trade at a high coupon:

1. Credit deterioration: the issuer's finances weakened, increasing default risk. Existing bondholders suffer mark-to-market losses, but new buyers demand higher yield to compensate.
2. Call risk: a callable bond might be called away if rates fall, capping upside. Investors demand higher coupon to compensate.
3. Liquidity risk: a small-cap corporate bond with few buyers trades at a wider spread (higher yield) than a large, liquid bond.
4. Structural subordination: the bond is subordinated to senior debt, so in a default, holders get less. Higher coupon compensates.
5. Sector stress: airlines, retail, shipping — these sectors go through boom-bust cycles. A healthy airline bond might trade at 5%, but if the sector is in trouble, all airline bonds widen, including good ones.

The coupon reflects the market's collective wisdom. If a bond yields 7% and most others yield 4%, the market is saying, "We think this bond is riskier than others."

Behavioral bias: the siren song of income

Humans are biased toward concrete rewards. A 7% coupon ($700 per year on $10,000) feels real and tangible. A 3% coupon ($300) feels meager. This is a cognitive bias that blinds investors to risk.

Research on loss aversion and mental accounting shows that investors overweight certain income and underweight uncertain losses. A retiree might think, "I'll earn $700, and if the bond defaults, well, that's tomorrow's problem." But default (if it happens) is a catastrophic outcome — you lose principal and income.

The media amplifies this bias by highlighting yields: "This bond fund yields 6%!" Good financial planning requires resisting the siren song of high coupons and asking: what risk am I taking for this coupon?

Yield trap: the classic mistake

A "yield trap" is a bond that appears to offer high yield but is actually a value destruction waiting to happen. Typical triggers:

1. Dividend cut imminent: a REITs or MLPs coupon might be at risk if the distributing entity's cash flow is declining.
2. Credit spread blow-out pending: a corporate bond trades at 5% on news that its biggest customer is leaving; the spread is about to widen, the price about to crash.
3. Maturity date misalignment: a bond maturing in 2 years looks safe, but the issuer has debt maturing in 1 year that it can't refinance; bankruptcy is possible.

Professional distressed-bond traders identify yield traps and short them (sell bonds they don't own, betting on a price decline). Retail investors often buy them, chasing yield.

To avoid yield traps, ask: Why is this bond yielding so much? Is it sector stress, credit deterioration, or just that the issuer is not well-known? If you can't articulate why the yield is high, you probably shouldn't own it.

The coupon bias decision tree

Practical example: the high-yield trap in 2023

In late 2022, many high-yield corporate bonds traded at 7–9% yields as the market feared a recession. A retail investor might have thought, "9% is excellent; I'll load up."

But in 2023, credit conditions stabilized and the recession didn't materialize. High-yield spreads tightened from 6.5% to 4%, and bond prices rose sharply. The investor who bought at 9% got both coupons and capital gains — great timing.

But those who bought the "bad" issuers (companies that actually did default or decline) lost money. Selective buying (only the strongest high-yield issuers) outperformed indiscriminate buying (all high-yield).

This is the coupon bias trap in action: high coupons attract broad demand, but the risk is real and concentrated in the weakest issuers.

A better approach: quality first, yield second

A more disciplined approach:

1. Start with a target allocation: 60% bonds, 40% stocks. Or 80% bonds if retired.
2. Allocate to bond categories by credit quality: 40% Treasury/high-grade corporate (AAA/AA), 20% investment-grade corporate (A/BBB), 10% high-yield if needed for income, 20% cash/short-term.
3. Within each category, favor yield: within investment-grade, buy A-rated bonds over AAA (higher yield for same credit quality). Within high-yield, select the most creditworthy BB issuers (lower yield than B or C, but less default risk).
4. Rebalance when spreads move: if high-yield spreads widen to 6%, increase high-yield allocation. If they tighten to 3%, reduce.

This approach respects the market's pricing while avoiding the coupon bias trap. You get yield, but you earn it by assuming only the risks you're compensated for.

Summary: coupon is not return

The coupon rate is what the bond pays if nothing goes wrong. The return is what you actually get, including defaults and price moves. For an income-focused portfolio, the worst outcome is a high coupon followed by a default — the fund is depleted by the very risk you were compensated (inadequately) for.

Scrutinize high-coupon bonds. The market prices risk; high coupons are signals, not gifts. Own high-coupon bonds only if you've convinced yourself that (1) the market is overpricing the risk, and (2) you can afford to lose principal if you're wrong.

Related concepts

• ./19-yield-spread-basics.md
• ./06-yield-to-maturity-ytm.md
• ./01-face-value-explained.md

Next

Some bonds trade at steep discounts (below par), others at premiums (above par). Those discounts and premiums come with tax consequences and different reinvestment profiles. The next article explores the trade-offs between deep discount and premium bonds.