Mattress Looks Misshapen

Sleep Number^® beds are designed to conform to the body to eliminate pressure points. When you sleep on a Sleep Number bed, the body displaces the air in the air chamber. This can leave an impression where you sleep when the bed is set to a lower Sleep Number^® setting. 

Quick answer

If your mattress looks uneven, sagging, lumpy, or one side is lower than the other, start with these checks. Some changes are normal after setup or with low firmness settings, but air loss, deep sagging, or a side that will not inflate may need more help.

Start here: What do you see?

• One side is lower than the other? Start by increasing firmness and checking hose connections.
• The mattress loses air overnight? Check hoses, caps, and pump connections. This may be an air leak.
• You feel a dip, divot, or “hammock” effect? Increase firmness, then check foam and air chamber placement.
• You see a lump, ridge, or bulge? Inspect the foam and air chamber alignment if your mattress cover opens.
• The foam or cover looks worn, torn, or compressed? You may need a replacement part or support review.

What’s normal

• Temporary unevenness after delivery, setup, moving, or reassembly
• Small fabric wrinkles or waves on the top cover
• Slight changes in feel when the room is very cold or warm
• A lower Sleep Number setting making the mattress look less full when no one is in bed

What’s not normal

• One side will not inflate or will not hold air
• The mattress loses air overnight or drops far below your setting
• Deep sagging, a large dip, or a “sink hole” feeling that does not improve
• A lump, ridge, bulge, or chamber that feels out of place
• Foam, side rails, comfort layers, or the cover are torn, compressed, or no longer laying flat

How to fix it

1. Increase firmness and let the mattress fill

• Set both sides to 100 to fully fill the air chambers.
• Wait a few minutes, then smooth the top surface with your hands.
• If the mattress looks better at 100 but changes again at a lower setting, the lower setting may be causing the mattress to look less full.

2. Check for air loss or a side that will not inflate

• Make sure the hoses are connected securely to the mattress and pump.
• Check that the hoses are not bent, pinched, or pulled loose.
• If one side fills and then slowly deflates, the issue may be an air leak and may need support.

3. Check mattress position on the base

• Make sure the mattress is centered on the base.
• Check that the mattress is not hanging over the edge or pushed tightly against the headboard or footboard.
• If you have a split king or FlexTop mattress and see a large gap, the mattress sections may need to be realigned.

4. Inspect foam and air chamber placement

• If your mattress cover opens, unzip it carefully and check that the foam rails, comfort layers, and air chambers are flat and aligned.
• Look for foam that is folded, shifted, compressed, torn, or not sitting inside the cover correctly.
• If you see a large bulge, ridge, or air chamber that looks damaged, stop using that side and contact support.

5. Give a new or recently moved mattress time to settle

• If the bed is new, recently moved, or recently reassembled, allow 24–48 hours for the materials to settle.
• Cold rooms can make materials feel firmer or look uneven until they warm up.
• If the shape does not improve after 48 hours, continue to the next step.

6. Check whether you need a replacement part or service

• If the cover, foam, air chamber, or hose looks damaged, a replacement part may be needed.
• If the mattress is too heavy to move safely, ask another adult for help or contact support for service options.
• If you already tried these steps and the issue came back, contact support and mention what you checked.

Still need help?

Contact support if one side will not inflate, the mattress loses air overnight, you see torn or compressed parts, or the mattress is too heavy to safely adjust. Share your bed model, which side is affected, and whether the issue is sagging, air loss, a lump, or a gap.

FAQ

Why does my Sleep Number mattress look uneven?
It may look uneven because of a low firmness setting, setup changes, shifted foam, hose connection issues, or air loss.

Why does one side of my mattress keep losing air?
If one side fills and then slowly deflates, check the hose connection first. If the connection is secure and the side still loses air, contact support because there may be a leak.

Can I replace foam, a cover, or an air chamber?
Some parts may be replaceable depending on your bed model and warranty. Contact support with your model and purchase information to confirm options.