Do coil springs wear out?

Comfort and transition layers tend to wear out earlier than support layers because they are usually softer and less dense. The comfort system is more prone to body indentations, while support-core wear can cause broader structural problems.

Sleep Foundation estimates innerspring mattresses tend to retain their shape for 5.5 to 6.5 years, but this is a whole-mattress estimate, not a lifespan estimate for mattress coils alone. When coils are interconnected and cannot be compressed individually, sagging may develop over time.

Sleep Foundation says sleep position may influence where indentations eventually form. Heavier sleepers may wear a mattress faster than lighter sleepers, especially when it contains soft foam layers.

Sleep Foundation lists indentations, sagging, and visible wear among signs it may be time to replace a mattress. A mattress’s durability also includes retaining its original firmness, adequate support, safe use, and the same amount of hug or bounce.

Press for weak spots

Pressing can help find a weak spot.

• Press along the mattress surface.
• Find the exact spot that pokes or sinks.

Look for a lasting dip

A lasting indentation or sag may be a sign of mattress wear.

• For Nest Bedding’s measurement, leave the mattress flat and undisturbed for at least 2 hours before measuring.
• Tempur-Pedic says to measure without pressure using a straightedge; its listed thresholds are more than 1.5 inches for quilted tops and more than 0.75 inch for non-quilted mattresses.

If a mattress has internal damage, it likely cannot be repaired without manufacturer help.

In some cases, comfort or uneven-feel concerns may be related to the bed base rather than the mattress.

• Some slats can lose rebound and bow downward over time, so check for that.
• Some downward-bowing slats may reduce support for the mattress.

Coil gauge describes wire thickness, while pocketed coils move independently within fabric casings.

Thick or thin wire

Thicker coil wires typically last longer and provide better support.

• Check coil gauge when comparing wire thickness.
• A 13-gauge coil is thicker than a 15-gauge coil.

Pocketed coils

Pocketed coils have fabric sleeves that are sewn or glued together.

• Each spring moves independently within its fabric casing.
• Check whether a mattress uses pocketed coils when comparing coil movement.

The next step depends on whether the problem is an isolated damaged coil, a shallow impression, or internal damage.

Repair one coil

A DIY repair works best for one damaged mattress coil when the rest of the mattress is structurally sound.

• Gather needle-nose pliers.
• Choose zip ties or sturdy wire, plus fabric glue or a needle and thread.

Try a topper briefly

A topper may reduce the feel of shallow impressions when the support core is still in decent shape.

• It can improve comfort when the support core is still in decent shape.
• Check the frame, slats, box spring, and foundation before trying a surface fix.

Replace the whole mattress

A mattress with internal damage likely cannot be repaired without manufacturer help.

• A topper can cover flaws.
• A topper will not fix an old bed.

We read 10 published pages from 8 sites (Sleep Foundation, naplab.com, eachnight.com, nestbedding.com and 4 more), checked in October 2026. Every sentence in the answers above cites one of them; the offer card at the end names its own source. This page reports published sources only; we did not test mattresses in person.