How Thick Should a Mattress Topper Be?

When shopping for a mattress topper, it’s hard to know exactly what you’re looking for. From materials and firmness to size, there are many different options out there. One question you may be asking is how thick a topper should be. This depends on your personal preference, though here are some general guidelines to help you find your perfect match.

Why does the thickness of a mattress topper matter?

When it comes to mattress toppers, it’s not a case of one size fits all. It really depends on what you are using the topper for. If it is to rejuvenate and revitalise an older mattress, you are likely better off going for a thicker topper for extra cushioning and support, though for a newer mattress, a lower thickness could work best. There are other things to consider beyond the age of your mattress. Like, what is your firmness preference? And how much support are you looking to get from your Topper?

If your mattress is on the cheaper side and lacks dense, quality memory foam, your alignment will benefit from an orthopaedic-grade topper that gives it a bedtime boost. An unsupportive mattress can lead to an uncomfortable night’s sleep and aches and pains in all the wrong places. 

These are all things to consider before making your choice, and exactly how many inches are there to choose from?

What are the different thickness options for mattress toppers?

Mattress toppers can range in thickness from around 2-4 inches (5 to 10 cm). Here’s everything you need to know about the different sizes and what they work best for.

2-inch toppers 

A two-inch topper can provide a luxurious layer of comfort and support to your mattress and work especially well with newer mattresses. If you have an older mattress, you may find this thickness does add the comfort factor you are looking for. However, this does depend on the quality of the topper. This can make a difference if the topper is made from quality materials and advanced orthopaedic grade foam, like our bamboo memory foam mattress topper. This is why we offer a 30-night home trial for you to get to know each other.

3-inch toppers

A three-inch topper can provide more cushioning to older mattresses, though this depends on the materials and density you choose. If you prefer your sleeping surface to feel firmer, look for toppers with a higher, firmer rating and supportive memory foam.

4-inch toppers

4 inches tends to be the thickest a topper can be before it is classified as a mattress. The highest level of thickness can provide you with all the comfort and support an older mattress is likely lacking. If you are looking to totally upgrade your mattress without committing to the investment, a topper can provide a budget-friendly solution.

What should you consider when choosing the thickness of your topper?

Now you know the various thickness toppers can come in, here are a few other things to consider.

How old is your mattress?

The condition of your current mattress is key to how much you will benefit from a topper. If it is on the older side or of low quality, consider a higher thickness. The quality of materials is also key; orthopaedic-grade foams will naturally contour to your sleeping position, keeping you in perfect alignment and providing sufficient support throughout the night.

What is your firmness preference?

Remember the princess and the pea? It is like this when choosing a mattress topper. Finding the perfect thickness and bedtime feels like a fairy tale. When shopping for toppers, consider the firmness rating and types of foams used to be sure you find the right sleeping surface to keep you comfortable. 

Would you benefit from natural fabric?

If you tend to have sensitive skin or allergies, choosing a topper made with naturally hypoallergenic fabric like bamboo can help keep bedtime comfortable. Bamboo is antibacterial, fending off bacteria and dust mites that can cause irritation and help keep you resting comfortably.

Are you a hot sleeper?

Many of us can overheat at night, and choosing the right mattress topper can help. Our Bamboo Memory Foam Topper is made with cooling HydroFoam™ to keep sleep fresh and comfortable. Combined with our smooth, thermoregulating bamboo cover, our topper is a bedtime favourite for hundreds and thousands of happy sleepers.

Which size mattress topper should I choose?

Choosing the right size mattress topper is just as important as choosing the right thickness or material. A well-fitted topper ensures even comfort across the bed, prevents slipping, and provides the full benefit of pressure-relieving support.

UK Standard Mattress Topper Sizes

• Single (90 × 190 cm): Ideal for solo sleepers, teenagers or guest rooms. A single mattress topper offers full comfort and support in a smaller space.
  
• Double (135 × 190 cm): Perfect for couples or anyone looking to refresh a standard double bed without buying a new mattress.
  
• King (150 × 200 cm): For those who love more room to stretch out, a king-size topper provides luxurious coverage and balanced comfort.
  
• Super King (180 × 200 cm): Designed for maximum space and indulgent comfort, ideal for master bedrooms or larger beds.
  

To get the most from your topper, always match it to the exact size of your mattress — a proper fit prevents movement during the night and ensures consistent support.

If you’re unsure which size to pick, explore our full range of single mattress toppers, double mattress toppers and king mattress toppers to find the perfect fit for your bed.

Final Tips

A mattress topper can significantly improve the quality of your sleep and add years of comfort and support to your mattress. Remember, it can take a few weeks to adjust to the new feel of your mattress, so go for a topper that comes with a home trial. This way, you can make sure you’ve found the perfect fit without losing a wink of kip.

Ready to upgrade bedtime? Our Bamboo Memory Foam Topper will transform your mattress and have you sleeping soundly. Give it a try, with a 30-night home trial and free delivery, you will be falling in love with early nights in no time.