OTTY Bamboo & Charcoal Mattress Topper reviewed

The OTTY Bamboo & Charcoal Mattress Topper is a 5cm layer of open-cell memory foam infused with bamboo and charcoal, designed to soften a mattress that feels too firm. OTTY rates it 5.5 out of 10 for firmness and sells it in four UK sizes, from £99.99 for a single to £179.99 for a super king (September 2026).

Construction and certification

According to the OTTY product page, the foam is open-cell, which OTTY says breathes better than standard memory foam, and the underside has a grippy anti-slip base that stops the topper sliding on the mattress. The cover is removable but dry clean only, and the foam itself cannot go in a washing machine.

The same page lists the topper as CertiPUR certified. CertiPUR is run by EUROPUR, the European association of flexible foam producers. Certified foam is made without heavy metals such as mercury, lead and cadmium and without phthalate plasticisers, must emit low levels of volatile organic compounds, and is re-tested by independent laboratories every year of the label’s three-year validity. The mark covers the foam only, not the cover fabric.

Trial, guarantee and lifespan

The topper’s terms are much shorter than OTTY’s mattress terms. The product page gives a 14-night trial and a 1-year guarantee, against 100 nights and 10 years on the mattresses, so the 100-night banner that runs across the OTTY site does not apply here. OTTY’s own FAQ puts the life of a good memory foam topper at 3 to 5 years, depending on use and care. Even a short trial is worth having, since it lets you send the topper back after sleeping on it.

Who it suits

Softening a firm mattress is the job this topper is built for. A 5cm topper at 5.5 out of 10 suits side sleepers on a firm mattress who want more give at the shoulder and hip, and anyone extending the life of a mattress that is still supportive but hard on the surface. It will not rescue a mattress that sags. Memory foam follows the shape beneath it, so a dip in the mattress shows through the topper, so on a mattress that is already sagging, a new mattress is the better spend. On a double or larger bed one topper covers both sides, so couples who want different feels would need two single toppers instead. The breathability benefit of the bamboo and charcoal infusion is OTTY’s claim; there is no published independent temperature measurement for this topper.