A no-nonsense 2026 guide to mattress warranties: what they actually cover (and don't), the sag-depth thresholds that trigger replacement, the hidden rules that void claims, and a step-by-step process for filing - plus warranty length comparisons across Tempur-Pedic, Saatva, Casper, Purple, Nectar, and Sealy.
A mattress warranty is a manufacturer's promise to repair or replace your bed if it fails because of a defect - a coil that snaps, foam that cracks, a top layer that sags far below the floor of normal use. It is not a comfort guarantee, a no-questions-asked return policy, or a hedge against years of normal softening. The difference matters: a typical mattress warranty runs 10 to 20 years, and most claim denials we see come from buyers who confused the warranty with the trial period or who unknowingly voided coverage by removing a tag, using the wrong frame, or staining the cover.
This guide walks through what mattress warranties actually cover in 2026, the sag-depth thresholds that trigger a replacement, the everyday actions that void coverage, and the exact steps to file a claim that gets approved on the first pass. We also break down warranty length and claim policy across the eight brands we get the most questions about.
A mattress warranty is a contract between you and the manufacturer (not the retailer). It promises that if the bed fails due to a manufacturing defect within the warranty term, the manufacturer will repair, replace, or refund a prorated portion of the purchase price. Most warranties are limited - they cover specific failure modes (sagging beyond a threshold, coil breakage, seam separation, foam degradation) and exclude almost everything else.
Translation: a 25-year warranty that's only non-prorated for 2 years is weaker than a 10-year fully non-prorated warranty. Always read the structure, not the headline number.
Coverage varies by brand, but virtually every mainstream mattress warranty in 2026 covers four core failure modes:
A warranty is also distinct from a sleep trial. The sleep trial (typically 100-365 nights) covers comfort: if you don't like how the bed feels, you can return it. The warranty covers physical defects after that trial window closes. Confusing the two is the single biggest source of frustrated reviews online.
Manufacturers are strict on void conditions because the warranty has to function as a defect guarantee - not a misuse insurance policy. The five voiders below are responsible for the majority of denials we see at our review desk.
Warranty length is a rough proxy for manufacturer confidence in durability - but only when paired with the proration structure. Here's how the brands we get the most questions about stack up:
Warranty terms change. Always confirm coverage on the manufacturer's site at the time of purchase, and screenshot the policy for your records.
A successful warranty claim is mostly preparation. Manufacturers approve claims that are documented and obviously legitimate; they push back on claims that are vague or arrive without paperwork.
Most modern mattress warranties run 10 years (Casper, Tempur-Pedic, Purple, Helix), with some brands offering 15-year, 20-year, or 'lifetime' coverage (Saatva, Nectar, DreamCloud). Length only tells you how long you can file a claim - proration structure determines what you actually get back.
Most brands set the threshold between 0.75 and 1.5 inches measured with the mattress unloaded on a flat surface. Tempur-Pedic uses 0.75", Casper and Purple use 1", and Saatva, Nectar, and Sealy use 1.5". Anything shallower is treated as normal body impression and is not covered.
Yes - virtually every major manufacturer voids the warranty on any biological stain (sweat, urine, blood, etc.) for sanitary reasons. Inspectors will not handle a stained mattress. A washable mattress protector from day one is the simplest way to keep coverage intact.
No - file directly with the manufacturer, even if you bought from Mattress Firm, Costco, or Amazon. Retailers may help facilitate, but the warranty contract is between you and the manufacturer. You'll need the original receipt and a photo of the law tag.
A sleep trial (typically 100-365 nights) lets you return the mattress for a refund if it's not comfortable. A warranty (10-lifetime) covers physical defects - sagging, broken coils, split foam - for years after the trial period closes. Confusing the two is the most common reason people feel misled by mattress brands.
Almost never. Mattress warranties cover the original purchaser only - buying a used mattress voids the warranty even if the original purchase was recent. Always factor that into the price of a secondhand bed.
Our buying guides cover warranty length, return policy, and durability for every brand we review - start with our hybrid and memory foam roundups.
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Banner Mattress EditorialThe Banner Mattress editorial team publishes independent mattress reviews, buying guides, and sleep-health advice. Since 2018 we've tested 1,000+ mattresses and 3,000+ pillows, sheets, and bedding accessories in our review lab - every recommendation is hands-on, never sourced from vendor talking points. Affiliate links may earn us a commission, but never change what we recommend.
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