Soak&Sleep 4.5cm Memory Foam Mattress Topper reviewed

The Soak&Sleep 4.5cm Memory Foam Mattress Topper is a single layer of CertiPUR-accredited memory foam in a quilted, zip-off polyester case with a non-slip underside, sold in single, double, king and super king. It is the simplest way in the Soak&Sleep range to give an existing mattress the slow, contouring feel of memory foam.

Specification

All figures come from the Soak&Sleep product page. The foam feels firm to the touch and softens as it warms to your body, which spreads load across shoulders and hips; Soak&Sleep pitches it at people with aches who want a more neutral resting position. The topper arrives rolled in a vacuum pack.

What a topper can and cannot fix

A topper is usually a fix for feel rather than support. At 4.5cm, this one can soften a firm mattress, but no topper corrects a dip, so an old, sagging mattress is usually better replaced than covered.

Foam certification

Soak&Sleep says the foam is accredited by CertiPUR. Under the CertiPUR programme run by EUROPUR, certified foams are tested every year by independent laboratories against limits for substances of concern, and the label may only appear on products made entirely with certified foam. No certificate number is shown on the product page.

Heat

Memory foam holds warmth, and the product page says so itself, suggesting a cooling protector for people who overheat. If your bedroom already runs above the 16 to 18°C the Sleep Charity recommends, a wool topper will be the cooler choice. For day-to-day care, Soak&Sleep advises rotating the topper once a week or whenever you change the sheets, spot-cleaning spills with a mild detergent and keeping a protector over it, which saves the foam itself from ever needing a wash.

Prices by size

Prices were checked on soakandsleep.com in September 2026, when the single was out of stock. There is no small double or emperor. Delivery is free over £70; returns follow Soak&Sleep’s 365-day policy for unused items, and there is no sleep trial on toppers.