Bond Ladder

A bond ladder is an arrangement of several bonds with different maturity dates, so that part of the money comes due at regular intervals rather than all at one date. A holder with $250,000 and a five-year ladder might buy $50,000 of bonds maturing in each of the next five years, so that $50,000 is repaid every twelve months and can be spent or reinvested.

As with a ladder of certificates of deposit, the phrase is market vocabulary rather than a defined term. The MSRB's glossary of municipal securities terms has no entry for it and neither does the SEC's investor glossary, and it is not a product with its own legal character however a brokerage packages the idea. It is a way of holding ordinary bonds. The structure itself, the rule of renewing each maturing rung at the longest term, the assumption about the shape of the yield curve that the structure depends on, and the reasons a ladder can be worse than the simplest alternative are all set out under the CD ladder, and they apply here unchanged. What follows is only what changes when the rungs are bonds.

A rung is a security, so the early exit is priced by the market rather than by a contract. Reaching a bank certificate before maturity costs whatever the deposit agreement specifies, and that penalty is known in advance. Selling a bond before maturity means accepting whatever a buyer will pay. The SEC states the consequence plainly: an investor who sells before maturity "may get a far different amount," below face value if rates have risen since purchase and above it if they have fallen. There is also a cost that does not appear as a line item, because a broker may take a markdown built into the sale price rather than charging separately for the trade. So a bond ladder's flexibility is real and it is not free, and the price of using it is unknown until the day it is used.

Holding to maturity converts price risk into reinvestment risk, and that exchange is the structure's actual product. A holder who commits to keeping each rung until it is repaid never realizes a price loss on it. What that holder accepts instead is that every maturing rung has to be reinvested at whatever rates prevail on the day it comes due. Rising rates therefore stop being a threat and start being an opportunity, and falling rates stop being a windfall and start being a problem. Neither state is safer than the other. A ladder does not reduce interest rate risk; it chooses which half of it the holder carries, and it spreads the reinvestment half across several dates so that no single one determines the outcome for the whole sum.

Credit risk does not ladder, and this is the difference that catches people. A ladder of bank certificates at one institution is covered by deposit insurance up to the applicable limit, which applies to a depositor's total at that bank in each ownership category rather than to each certificate separately, so within that limit the failure of the bank is largely handled. A ladder of corporate or municipal bonds from one issuer has no equivalent. Five bonds from one company are one company's promise repeated five times, and if that company fails, every rung is impaired at once. Spreading maturities across five years addresses when the money arrives and does nothing whatever about whether it arrives.

That has a practical consequence for how much money a ladder needs. Making the credit genuinely diversified requires enough separate issuers on each rung, not merely enough rungs, so the sum required scales with both numbers at once, and it scales fastest for the corporate and municipal bonds where credit matters most. Any specific figure put on it is a rule of thumb rather than a rule, but the direction is not in doubt: below some size, a fund is the practical route to credit diversification, and a ladder of a handful of bonds is a concentrated position wearing a structure.

Where a ladder earns its place, which is a date rather than a yield. Matching each rung's maturity to money that is already scheduled to be spent gives something no fund offers: a known amount arriving on a known day, from a known issuer, without a sale. For a retiree covering the next several years of withdrawals, or for a household with a dated obligation, that is the argument, and it is an argument about certainty of timing rather than about return. A ladder built from Treasury securities takes that as far as it goes, because the credit question largely disappears and only the timing benefit remains.

Decide how many years the ladder should span, divide the money into that many parts, and buy bonds maturing one year apart. As each rung matures, either spend the proceeds or buy a new bond at the far end of the ladder. The difference from a ladder of bank certificates is in what each rung is, not in how the schedule is built.

A hypothetical example of the credit point, which is the one specific to bonds. Rosa builds a five-rung ladder with $250,000, putting $50,000 into bonds maturing in each of the next five years. She buys all five from the same corporate issuer because the yield was attractive and the paperwork was simpler.

In year two the issuer defaults, and bondholders eventually recover 40 cents on the dollar. Rosa does not lose one rung. She loses 60 percent of all five, because the rungs were never separate promises: $250,000 × 0.60 = $150,000 gone, and the maturity schedule she built made no difference to any of it.

Had she instead used five different issuers, one per rung, a single default would have cost 60 percent of one $50,000 rung, or $30,000. Had she used Treasury securities, the question would not have arisen in that form at all. The lesson is not that ladders are unsafe. It is that the safety a ladder provides is about timing, and credit has to be handled separately.

A second hypothetical, on the exit. Rosa needs money unexpectedly in year one and sells the rung maturing in year five. Market yields have risen since she bought it, so the bond is worth less than she paid, and the broker's markdown comes out of the price she receives. Selling the rung that matures next year would have cost her much less, because a bond with little time left moves little when rates move. Which rung gets sold is a decision, and on a ladder it is usually the shortest one.

Pros

• A known amount arrives on a known date from a known issuer, without a sale, which is something a fund structurally cannot offer.
• Maturities can be matched to spending that is already scheduled, so the market's level on any particular day stops mattering for that money.
• Holding each rung to maturity means price movements along the way never become realized losses.
• Reinvestment is spread across several dates, so no single day's rates determine the return on the whole sum.
• Each maturity is a natural review point, which is a reason to reconsider whether the money should still be in bonds at all.

Cons

• Credit risk is unchanged by the structure, and a ladder built from one issuer is a concentrated position however many rungs it has.
• Genuine credit diversification needs several issuers on every rung, so the sum required is much larger than the number of rungs suggests.
• Selling a rung early means accepting the market price plus an unstated markdown, which is less predictable than a stated early withdrawal penalty.
• It carries the same yield curve assumption a CD ladder does, and fails in the same way when short maturities pay more than long ones.
• Buying individual bonds in small sizes is more expensive per dollar than buying a fund, and the cost is usually inside the price rather than itemized.
• It is more administration than one holding, with several maturity dates and several reinvestment decisions to make on time.