Two numbers get quoted on every mattress product page: the trial length and the warranty term. Both are real, and both are less useful than they look, because the clauses that determine whether they pay out are three clicks away in a PDF.
Here is what to read, and what the brands we test actually commit to.
Trial periods
The break-in clause
Almost every trial includes a mandatory period — typically 21 to 30 nights — before you may return the mattress. This is not a trick. Adaptation to a new support surface genuinely takes two to four weeks, and the clause exists because returns inside the first week are overwhelmingly people who have not adjusted yet.
The effect is that a "100-night trial" is really about seventy nights of informed judgement. On a 365-night trial the deduction is irrelevant.
The return fee
The number that is never on the product page. Among the brands we track it ranges from zero to $99 per mattress, and on a split King it is sometimes charged twice.
What "free returns" actually involves
Even where returns are free, you are usually required to be present for a collection appointment, and the mattress must be clean and undamaged. Several brands donate rather than collect, in which case you need a receipt from the charity to release the refund.
None of this is unreasonable. It is simply more effort than "365-night risk-free trial" suggests, and worth knowing before you order two mattresses intending to send one back.
Trial terms, brand by brand
| Brand | Trial | Break-in | Return fee |
|---|---|---|---|
| Saatva | 365 nights | None stated | $99 |
| WinkBeds | 120 nights | 30 nights | Free after break-in |
| Helix | 100 nights | 30 nights | Free |
| DreamCloud | 365 nights | 30 nights | Free |
| Nectar | 365 nights | 30 nights | Free |
| Brooklyn Bedding | 120 nights | 30 nights | $99 |
Warranties
The sag threshold is the whole document
Every mattress warranty is really one number: how deep a permanent indentation has to be, measured with nothing on the bed, before the manufacturer accepts it as a defect.
Common thresholds are 0.75 inches and 1.5 inches. Our own testing puts the onset of noticeable discomfort at around 0.5 inches, and clear discomfort at 0.75. A 1.5-inch threshold therefore means the mattress must be substantially unusable before it is claimable.
A ten-year warranty at 0.75 inches is worth more than a lifetime warranty at 1.5 inches. This is the single most useful thing in this guide.
Pro-rated versus replacement
A replacement warranty gives you a new mattress. A pro-rated one gives you a discount on a new mattress, scaled by how long you have owned the old one — typically you pay a percentage equal to the years elapsed.
Most "lifetime" warranties are replacement for the first ten years and pro-rated after that, which is reasonable and rarely explained. WinkBeds is the outlier among brands we track: its terms replace rather than pro-rate for the full initial period.
What voids it
Consistently, across every brand we have read:
- A non-compliant foundation. Slat gaps over three inches, or a base without a centre support on a Queen or larger. This is the most common denial reason.
- A removed law tag. The one you are legally permitted to remove, and which every warranty requires you to keep.
- Stains. Any visible stain, including water. A protector is not optional if you intend to claim.
- No proof of purchase. Keep the receipt with a photograph of the tag.
What is never covered
Comfort. If the mattress is too firm or too soft, that is what the trial period is for; no warranty in this category covers a mattress you dislike. Normal softening of comfort layers — around 10% in the first month — is also excluded everywhere, correctly.
How to use both properly
- On delivery: photograph the law tag, keep the receipt with it, and check the foundation meets the stated requirement.
- Fit a protector immediately. A breathable, non-waterproof one if you can — waterproof membranes add about 0.9°F to overnight surface temperature in our measurements.
- Set the trial reminder. Two-thirds of the way through the window.
- Judge at week four, not week one. Firmness that feels wrong on night two is usually adaptation; see the the best mattresses for back pain guide for how to tell the difference.
- Measure annually. A straight edge across the bed once a year tells you whether you have a claim before it becomes an argument. The method is in when to replace a mattress.