The best dust mite protector in the UK: what actually blocks mites, and what only says it does

Search "anti allergy mattress protector" and you get £15 fitted sheets, £40 waterproof encasements and £200 medical-grade sets, all claiming to stop dust mites. Most of them don't. This guide explains the five things that decide whether a protector works, compares the main UK options on those five things, and tells you which to buy first.

Our pick: the iDustMite Protector Set Jump to the comparison

✔ NHS backed · ✔ Blocks 100% of dust mites · ✔ Lab-tested 5 micron barrier · ✔ Feels like silk, not plastic · ✔ Free UK next-day delivery · ✔ 1 year warranty

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Why most "anti allergy" protectors don't work

Dust mites live inside your mattress, pillows and duvet, not on the surface. An adult mite is about 300 microns long. Its droppings, which are what you are actually allergic to, are 10 to 40 microns. Ordinary bedding fabric has gaps of 100 microns or more, so mites and allergen move through it freely.

A fitted "anti allergy" protector covers the top of the mattress with a treated fabric and leaves the sides and underside open. Mites inside the mattress keep breeding and their allergen keeps reaching you through the open sides and around the elastic. The treatment on the fabric does nothing about that. This is why so many people buy one, feel no better, and conclude that "protectors don't work". The protector was never sealing anything.

The five things that decide whether a protector works

1. Full encasement, not a fitted sheet. It must cover all six sides of the mattress and zip shut. The same goes for pillows and the duvet: a pillowcase or duvet cover is not an encasement.
2. A tested pore size under 10 microns. Below 10 microns stops the allergen, not just the mite. If a product does not state its pore size, assume it is not small enough.
3. A sealed zip. The zip is the weak point. It needs an end stop or a flap under it, otherwise mites and allergen pass through the gap at the end of the zip.
4. Breathable, not waterproof. Waterproof protectors use a plastic (polyurethane) layer that holds heat and sweat against you. A warm, damp bed is exactly what dust mites need, and it is why waterproof encasements feel clammy. You want a barrier that stops allergen but lets moisture out.
5. Washable at 60°C. 60°C kills mites. If the protector can only be washed at 40°C, mites and allergen on the outside of it survive every wash.

How the main UK options compare

Prices and specifications checked 12 October 2026 from each brand's own listings. Prices change; check the retailer before buying.

What the table tells you

Only two of the five options actually seal the whole bed against dust mites: iDustMite and Astex. Both are full encasements with a stated pore size under 10 microns, both wash at 60°C, and both carry an allergy-specific credential. If you are choosing on dust mite protection alone, those are the two to look at.

Protect-A-Bed is a bed bug and spill product first. It is a good encasement for that job, but its waterproof layer is the thing that makes it warm, and the standard pack leaves your pillows and duvet open.

High-street fitted protectors and budget marketplace encasements are not dust mite protectors, whatever the label says. They either leave five sides of the mattress open or do not state a pore size, and most can only be washed at 40°C.

Why we rate the iDustMite Protector Set as the best overall

Astex is a respected UK product and costs less. Where the iDustMite Set wins is on the things people stop using a protector for.

• It feels like silk, not a hospital sheet. The eucalyptus silk surface is why customers tell us they forgot it was on. A protector that feels clinical ends up in the cupboard, and a protector in the cupboard blocks nothing.
• The barrier is lab tested at 5 microns and blocks 100% of dust mites and their allergen, with the NHS behind it.
• It is one set, delivered next day, that seals the mattress, both pillows and the duvet together. Most people who buy the mattress cover alone are back for the pillows within a month, because that is where their face is.
• Deep sizes up to 45cm for pillow-top and hybrid mattresses, cot to super king, with a free size exchange if you measure wrong.
• A real person on the phone. Call 0330 122 1646 and you speak to someone who has fitted hundreds of these and will tell you which size and which layer order you need.

Shop the Protector Set → Find your size

Which protector should you buy first?

If the Set is more than you want to spend today, buy in this order. Each step on its own makes a measurable difference, and you can add the rest later.

1. Mattress encasement. The mattress holds the largest mite population by far. Single from £149.
2. Pillow encasements. Your face is on the pillow for eight hours. Set of 2 from £79.
3. Duvet encasement. The duvet lies on top of you all night and is washed least. Single from £139.

Not sure? Read What to buy first, or call us.

Questions people ask before choosing

Does a mattress protector alone stop dust mite allergy?

It helps, and it is the right first step, but it leaves your pillows and duvet untouched. For most people with night-time symptoms, sealing the pillows makes the next biggest difference, because that is where you breathe.

Is the iDustMite protector waterproof?

No, and that is deliberate. The mattress and pillow encasements use a breathable 5 micron barrier that stops allergen but lets moisture out, so the bed stays cool and dry. Waterproof protectors trap heat and sweat, which is what dust mites thrive on. If you need waterproofing for spills, use a cheap waterproof sheet on top of the encasement.

Will it feel plasticky or crinkle?

No. The surface is eucalyptus silk. It is quiet and cool and feels like good bedding. Customers with sensory sensitivities tell us this is the one they can actually sleep on.

How often should I wash it?

Fit it, then wash it at 60°C every 4 to 8 weeks with your normal bedding. It does not need washing before first use.

Do I still need a normal mattress protector or sheet on top?

You can put your usual sheets and duvet cover straight over the encasements. Washing those weekly at 60°C removes any allergen that settles on the outside.

Can I claim VAT relief?

Yes. If you have a dust mite allergy, asthma or eczema you can buy without the 20% VAT by making a short declaration; email hello@idustmite.com and we set the order up for you. See our VAT relief page.

What about bed bugs?

The same six-sided encasement traps bed bugs in and keeps new ones out. See our bed bug mattress encasement.

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The short version

A dust mite protector only works if it encloses all six sides, has a pore size under 10 microns, seals the zip, breathes, and washes at 60°C. Two UK products do that properly. One of them feels like silk, blocks 100%, is NHS backed, arrives tomorrow, and seals the whole bed in one go.

Shop the iDustMite Protector Set →

Competitor details are taken from the brands' own published listings on 12 October 2026 and are given for comparison only. iDustMite is not affiliated with Astex, Protect-A-Bed or any retailer named. If you spot an error, email hello@idustmite.com and we will correct it.