Mattress Topper Sizes & Depths

Mattress toppers come in a variety of sizes and depths so you can find the perfect topper for your needs.

We have toppers available in the following sizes:

  • Single mattress toppers
  • Double mattress toppers
  • King size mattress toppers
  • Superking mattress toppers

We also stock mattress toppers that range from 2.5cm to 5cm deep.

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Mattress topper sizes

Your mattress topper should be the same size as your mattress to keep it from stretching or sliding about.

Here is a list of the different mattress topper sizes we stock at Mattress Online, and their dimensions:

Topper sizeDimensions
Single90cm x 190cm (3' x 6'3")
Double135cm x 190cm (4'6" x 6'3")
King150cm x 200cm (5' x 6'6")
Superking180cm x 200cm (6' x 6'6")

If you’re looking for a ‘queen size mattress topper’, you may struggle to find one from a UK website or shop. This is because ‘queen size’ is actually an American term. They are slightly larger than a UK standard king size, measuring 152cm x 203cm (or 60" x 80").

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Mattress topper depths

Our mattress toppers range from 2.5cm deep - with the Silentnight Impress Memory Foam 2.5cm Mattress Topper - to 5cm deep - as seen on the Silentnight Luxury Deep Sleep Ultimate Mattress Topper.

The Silentnight Luxury Deep Sleep Ultimate Mattress Topper on a Silentnight mattress and divan bed. The text overlay says '5cm deep' and 'Extra deep for ultimate comfort'.
The Silentnight Luxury Deep Sleep Ultimate Mattress Topper is our deepest mattress topper

Is it better to get a thicker mattress topper?

The thickness of your mattress topper should be dependent on how much you’d like to change the feel of your mattress and what type of topper you are looking to buy.

If you only want to take an edge of firmness off of your mattress or add a little bit of comfort, a thinner mattress topper is perfectly fine.

If you’d like to drastically change how your mattress feels, whether this is in terms of support or comfort, a thicker mattress topper may be better for you.

By using thinker toppers, you are putting more material between your body and the mattress beneath you. The fillings inside thicker toppers are usually also dense, which may help to mask the feel of your mattress if you find it uncomfortable.

If you’re looking for an extra thick mattress topper, check out our Silentnight Luxury Deep Sleep Ultimate Mattress Topper!

Should a mattress topper be bigger than the mattress?

No, your mattress topper should be exactly the same size as your current mattress. 

If your mattress topper is too big for your mattress, then it is more likely to slide across the surface while you sleep.

But if your mattress topper is too small for your mattress, you risk damaging the topper by stretching it too far. This will also put additional pressure on your mattress.

Person testing a mattress topper's size on their mattress
Ensure that your mattress topper fits snuggly to the mattress and is not too loose or too tight

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Now you know which mattress topper size and depth you’re looking for, why not check out our range of mattress toppers today?

Or, if you’re looking for additional information on mattress toppers, we have more advice for you below: