Wellynap Sofa Bed Mattress, 4-Inch

Key points

Some sleeper-sofa owners want a simple replacement that folds into the frame, others are looking for a thicker mattress for everyday use. The Wellynap is designed for the first job: a 4-inch foam mattress sized 72" x 58" for a queen-size sleeper sofa, with a gel memory foam top layer and a firmer foam base.

Its 0.5-inch gel memory foam layer sits over 3.5 inches of high-resilience foam. A removable, machine-washable cover and a non-slip bottom fabric add practical touches for a bed that gets folded away between visits. The product is also listed as CertiPUR-US and OEKO-TEX certified.

A solid pick if you need a sofa-bed replacement for occasional guests and want a cover you can remove for cleaning. Keep in mind that sleeper frames vary, so the stated queen size alone does not guarantee a fit. The 4-inch profile is also a compact sofa-bed format, not a full-height mattress for shoppers seeking a thicker bed.

Quick sizing guide

The listed dimensions are 72" long, 58" wide, and 4" thick. Measure the inside of the sleeper frame or the mattress you are replacing, rather than relying only on the sofa’s queen-size label. A small difference in a fold-out frame can affect whether the mattress sits flat or folds smoothly.

This size is intended for queen-size sleeper sofas, and the product description also names RVs, boats, and guest rooms as possible uses. Those settings can have their own space constraints, so compare the available sleeping area with all three dimensions before choosing it. If the mattress must fold with a specific frame, its measurements matter more than the room name or bed category.

Tips for day-to-day use

For a guest visit, unfold the sofa bed and check that the mattress lies evenly within the frame before making it up. The non-slip fabric on the bottom is intended to help it stay in place, while the foam construction keeps the design foldable for storage inside a sleeper sofa. This is a more space-conscious approach than keeping a separate full-size guest bed, though the thinner profile may not suit people who specifically want a deeper mattress.

The zippered cover can be removed and machine-washed, which is useful after guests leave. Follow any care instructions supplied with the mattress, since the product details do not specify washing settings. The gel-infused top layer is presented as a way to help dissipate heat, individual comfort can still depend on the sleeper and the rest of the bedding.

Questions before you buy

Is this mattress made for every queen sleeper sofa? No fit is guaranteed by the size label alone. Compare the frame’s interior or the existing mattress with 72" x 58" x 4" before buying.

Can the cover be washed? Yes. The cover has a full zipper and is described as removable and machine-washable, specific wash settings are not provided here.

What is inside the mattress? It has a 0.5-inch gel memory foam top layer over a 3.5-inch high-resilience foam base, plus a knit cover and non-slip bottom fabric.

Final verdict

Choose the Wellynap if those measurements match your sleeper sofa and you want a foldable replacement with a washable cover for guest use. It might not be a great match if your frame has different interior dimensions or you are shopping for a thicker mattress intended to feel like a conventional bed. The key decision is fit first, then whether a 4-inch foam profile suits the way you expect to use the sofa bed.