Naturalmat Tremendous Topper reviewed

The Naturalmat Tremendous is a 7cm topper with a natural latex core layered top and bottom with cashmere and organic wool, the thickest and most expensive topper Naturalmat makes. It is handmade to order in Devon to transform an uncomfortable mattress, and at the time of writing (September 2026) it costs £720 in a single and £880 in a Naturalmat double (137 x 190cm).

Construction

Naturalmat lists four materials on the Tremendous product page.

Naturalmat says the cover passes UK fire-safety rules without flame-retardant chemicals. The Furniture and Furnishings (Fire) (Safety) Regulations 1988 set the ignitability tests for mattress fillings, and the company states compliance with BS 7177 at medium hazard.

How it feels and who it suits

Naturalmat publishes no firmness grade for its toppers. We rate the Tremendous medium at 4/10, a touch softer than the Terrific, because the extra cashmere and wool padding sits over a similar latex core. Naturalmat pitches it at two jobs: rescuing a mattress that has become uncomfortable, and cooling down a memory foam bed by adding natural fibres on top. It suits side and back sleepers who want a plush but not sinking surface. Stomach sleepers and anyone who wants to firm a bed up should look at a firmer latex topper instead.

The cooling claim deserves a caveat. Wool and latex breathe better than dense memory foam, but a University of Sydney sleep-lab study in Nature and Science of Sleep (Shin et al., 2016) found no measurable effect on sleep from swapping polyester bedding for wool, even though wool sleepwear helped people fall asleep faster. Expect a drier, less clammy surface rather than a cold one. Naturalmat also asks you to turn its toppers every three months, because natural fibres compress slightly where you lie, a settling its guarantee treats as normal.

How it compares with the other Naturalmat toppers

Prices by size

Buying terms and the maker

Delivery is free and takes three to five working days; made to measure adds £50. The Naturalmat guarantee on adult toppers is 2 years, a short term for a topper that costs more than £1,000 in the larger sizes, and toppers are excluded from the 45-day Sleep Promise, so you get the standard 14-day return window with return postage at your cost. Naturalmat has made beds in Devon since 1999 and has been a certified B Corp since February 2023, scoring 96.3 on B Lab's impact assessment against a qualifying mark of 80.