Smooth Top Shell – Stretch Knit Cover for Sleep Number Beds

Stretch Knit Replacement Cover Built for Newer Sleep Number Beds

If your Sleep Number mattress cover is sagging, stained, torn, or losing its stretch, our Smooth Top Shell is a direct-fit replacement built to match the look and feel of the stretch knit tops Sleep Number has used on its newer mattresses since 2020. It's the same single-zipper construction as our popular Euro Top Shell — just with the modern smooth knit surface instead of the older quilted style.

Custom-fit for your exact mattress height. Sleep Number beds come in heights from 8" all the way up to 15" depending on the model and any pillow tops or layers you've added. Choose the height that matches your bed today and we'll build the cover to fit — no bunching, no stretching, no gaps at the zipper.

Compatible With These Sleep Number Models

This cover is designed to fit Sleep Number 360 Smart Bed models from approximately 2020 through early 2026, including:

Classic Series: c1, c2, c4 Smart Beds
Performance Series: p5, p6, pSE Special Edition Smart Beds
Innovation Series: i8, i10, iLE Limited Edition Smart Beds
Memory Foam Series: m7 Smart Bed
Climate Series: ClimateCool (2024), Climate360 (2022)

Not sure which model you have? Check the law tag on the side of your current cover or measure the mattress height — we'll help you pick the right fit.

⚠️ Looking for a quilted cover? If your Sleep Number bed has a quilted or Euro top surface (typical of pre-2020 models), you'll want our Euro Top Shell instead.

What Makes the Smooth Top Shell Different

Stretch knit top fabric that moves with the air chamber instead of bunching
Durable woven side panels in light gray, matching the look of newer Sleep Number borders
Heavy-duty single zipper with a smooth-pull tab — no flimsy plastic teeth
Reinforced corner seams at every stress point
Machine washable top panel (cold, gentle cycle, line dry)
Custom-sewn to your mattress height — not a one-size-fits-all stretch fit

Available Sizes

Twin (38" × 75")
Twin XL (38" × 80")
Full (54" × 75")
Queen (60" × 80")
King (76" × 80")
California King (72" × 84")
King Split Head Flex Top

Available Heights

8", 9", 10", 11", 12", 13", 14", and 15" — select at checkout.

Shipping information

Takes Around 3-5 Business Days to make.

Ships Out via Fedex Ground

Free Shipping

Key Features

Designed for Sleep Number stretch knit models (2020–early 2026)
Premium stretch knit top with woven gray side panels
Single-zipper construction for fast, tool-free replacement
Custom height options from 8" to 15"
Fits Twin through King Split Head Flex Top
Machine washable top
Made in the USA

Frequently Asked Questions

Will this cover fit my Sleep Number i8 / i10 / c2 / c4 / p5 / p6 / m7?

Yes. The Smooth Top Shell is designed to fit all Sleep Number 360 Smart Bed models from approximately 2020 through early 2026 that came with a stretch knit cover, including the c1, c2, c4, p5, p6, pSE, i8, i10, iLE, m7, ClimateCool, and Climate360.

How do I know if I have a stretch knit cover or a quilted cover?

Stretch knit covers have a smooth, stretchy-textured surface that gives slightly when you press into it. Quilted covers have visible stitched diamond or square patterns and a thicker, padded feel. If your current cover stretches and has a swirl pattern, this is the right replacement.

What's the difference between this and the Euro Top Shell?

The Euro Top Shell has a quilted top designed for older Sleep Number models. The Smooth Top Shell uses a stretch knit top to match the construction Sleep Number switched to on newer beds. Both use the same single-zipper system and are custom-sewn to your mattress height.

How do I measure my Sleep Number mattress height?

The most accurate way to ensure you get the right size cover is by unzipping your cover and measuring the total height of all foam and components that go inside your inside your current zippered cover.
Common heights are 10" (c-series), 11"–12" (p-series and m7), 13"–14" (i-series and ClimateCool), and 15" (Climate360 and iLE).

Is this an official Sleep Number replacement cover?

No. This is an aftermarket replacement cover designed to fit Sleep Number beds. We are not affiliated with or endorsed by Sleep Number Corporation. We are a Family-Owned Business since 1979 located in Pottstown, PA

How long does shipping take?

All Smooth Top Shells ship out on Wednesdays. If the order is placed before we close on Monday, It ships out Wednesday. After Monday, orders will ship out the following Wednesday.

Can I wash this cover?

The stretch knit top unzips for machine washing on cold, gentle cycle. Line dry only. Do not put in the dryer, as heat can damage the zipper.

What if I'm between heights. Should I size up or down?

Always size up. A slightly loose cover can be tucked smooth, but a cover that's too short won't zip closed properly.

Smooth Top Shell | Premium Single-Zipper Replacement Cover for Sleep Number Beds | Stretch Knit Top for Newer Models | Custom Fit for Your Mattress Height (8", 9", 10", 11", 12", 13", 14", 15" Options)