How to measure a body impression the way a warranty claim requires, which depths brands treat as defects, and what sagging is not covered.
A mattress may develop surface softening or a visible body impression as its materials settle. An unloaded impression can be relevant to a warranty claim, but depth alone does not determine whether a defect is covered. The model, foundation, applicable warranty and measurement method all matter.
| Observation | Usually | What to do |
|---|---|---|
| Slight surface softening in month one or two | Normal settling of comfort layers | Nothing; rotate if permitted |
| Indentation only while weight is on the bed | Not necessarily a visible warranty impression | Check the terms and foundation; rotate only if the maker permits |
| Impression still present with nothing on the bed | Potential warranty defect | Measure and photograph before filing |
| Dip at one edge only | Could involve the mattress or its support | Document the mattress and inspect the base |
| Hammocking across the middle of a queen or larger | Could involve the mattress or center support | Photograph the existing setup and ask about compatible support |
How to measure an impression correctly
Strip the bedding and leave the mattress unweighted, following the manufacturer’s instructions for any waiting period and test surface. Place a straightedge or taut string across the affected area, resting on the surrounding surface, and measure the deepest vertical gap without pressing into the bed. Photograph the reference line and ruler together. The manufacturer may have specific instructions for a quilted surface, foundation or image angle; see our detailed measurement guide.
Manufacturers can differ on the tool and measurement surface. For instance, Avocado’s warranty specifies tailor’s tape, while its claim article describes a ruler or tape and a specific support surface. Ask the brand which instructions apply before moving the mattress or taking claim photos.
The thresholds brands publish
Most warranties state a specific depth. Published thresholds vary by brand and model, and the exact wording matters: “greater than” a measurement differs from “equal to or greater than.” A threshold is only one part of the claim review. Our stored thresholds, with the brand’s own quoted language, are listed in the warranty guide and in our full warranty comparison.
Why the foundation is the first suspect
An inadequate base can contribute to a sagging appearance: check for broken or bowed slats, gaps wider than allowed, and missing center support where required. Photograph the existing setup before changing it. A warranty administrator may ask for evidence that the mattress has been properly supported. See slat spacing and foundation requirements for the measurements to take.
What sagging warranties do not cover
Many warranties exclude changes in comfort preference and ordinary softening, while their treatment of stains, foundation damage, commercial use and cover removal varies. A mattress that feels too soft without a visible dip may not meet an indentation criterion, but other covered defects may exist. Read the warranty for your model and purchase date; a prorated remedy can require the owner to pay a share of replacement costs. Construction and durability explains which builds tend to soften early in the first place.
What to do before filing a claim
- Find the receipt, law tag and warranty for the exact mattress and purchase date.
- Photograph the uncovered, unloaded mattress and any indentation with a straightedge and ruler. Follow the brand’s stated measurement method.
- Photograph the foundation, center support and slat gaps before changing the setup. Check whether the base meets the manufacturer’s requirements.
- Contact the seller or warranty administrator and ask which photographs, inspection steps and documentation are required. If your purchase was through Yawnder, start with the terms for your order.
- If the claim is denied, request the reason and relevant warranty language in writing and ask whether additional documentation can be reviewed.
For manufacturer examples and the distinction between a comfort return and a defect claim, see the sagging warranty guide and claim checklist.
Can you fix it instead?
Sometimes, temporarily. If the manufacturer permits it, rotating the mattress, addressing a base problem, or adding a topper may change comfort when the impression is shallow — our guide to fixing a sagging mattress covers what actually helps. None of it restores foam that has already broken down, and none of it should be done before you measure, because adding a topper hides the evidence a claim needs.
Related guides
Back to the Mattress Care & Ownership guide.
Frequently asked questions
How much sagging is normal in a new mattress?
Some surface softening may occur as materials settle. A visible impression without weight is relevant to many warranties, but other defects and conditions can matter too.
How do I measure mattress sag for a warranty claim?
Strip the bed, leave it unweighted, run a taut string or straight edge across the deepest point resting on untouched areas, and measure the gap. Photograph the measurement.
What sag depth counts as a defect?
It depends on the model and the warranty applicable to the purchase. Check the exact threshold, whether equality counts, and the other claim conditions.
Will a topper fix a sagging mattress?
It can mask a shallow impression and improve comfort, but it does not restore support and it can complicate a warranty claim. Measure first.
Can the wrong bed frame cause sagging?
Yes. Wide slat gaps, a damaged frame or missing required center support can contribute to sagging; the mattress itself may also be involved.