Duration vs. Maturity: What's the Difference?
Two bonds can mature on the exact same date years from now and still respond very differently to a change in interest rates. The reason comes down to a distinction that maturity alone doesn’t capture.
The short answer
Maturity is simply the date a bond’s principal is scheduled to be repaid in full, while duration measures how sensitive a bond’s price is to changes in interest rates, expressed in a time-like unit. A bond’s duration is generally shorter than its maturity, and the size of that gap depends heavily on how much and how often the bond pays interest along the way.
What maturity actually tells you
Maturity is a fixed, known date on a calendar. A ten-year bond matures in ten years, full stop, and that number doesn’t shift based on interest rates, coupon payments, or anything else about the bond’s structure. It’s a useful fact, but on its own it says very little about how much the bond’s price will move if rates rise or fall in the meantime.
What duration adds to the picture
Duration accounts for the timing of all the cash flows a bond pays, not just the final principal repayment. Every coupon payment made along the way returns a little of the investment early, which effectively shortens the average time an investor’s money is at risk. A bond that pays no coupons at all has a duration equal to its maturity, because the entire payment comes at the end. A bond with a high coupon returns cash earlier and more often, which pulls its duration below its maturity.
Why coupon size matters so much
- Higher coupon, shorter duration. More of the total return arrives before maturity, so the weighted average timing of cash flows moves earlier.
- Lower coupon, duration closer to maturity. Less cash arrives early, so more of the bond’s value depends on that final, distant principal payment.
- Zero coupon, duration equals maturity. With no interim payments, the entire cash flow timing sits at the maturity date itself.
Why this distinction matters for comparing bonds
Two bonds maturing in the same year can carry very different interest rate risk if one has a high coupon and the other a low one. Relying on maturity alone to compare how bonds might react to a rate change can be misleading, since a lower-coupon bond with the same maturity date will typically be more sensitive to rate moves than its higher-coupon counterpart. This is one reason duration, not maturity, is the more common reference point for discussing a bond’s interest rate exposure, alongside related measures like yield to maturity and bond convexity for a fuller picture of price behavior.
Where this shows up in everyday bond comparisons
When comparing something like a corporate bond to a government note with a similar maturity date, the coupon structure can make one meaningfully more sensitive to rate changes than the other, even though both mature on similar timelines. Looking at duration alongside maturity, rather than maturity by itself, gives a more accurate sense of what a rate move might do to price.
The bottom line
Maturity answers “when do I get my principal back,” while duration answers “how sensitive is this bond’s price to interest rate changes.” They’re related but distinct, and conflating them can lead to an inaccurate sense of a bond’s actual interest rate risk.