How to Choose the Right Mattress for Your Body Weight

Being completely honest, choosing a mattress can feel overwhelming at times.  

With all the options out there, how do you know which one is right for you? From the type of mattress and size to the firmness of a mattress, there’s a lot to think about. And one of those key factors people often overlook when mattress shopping is their body weight. Yes, even the way your body interacts with a mattress can make all the difference in how comfortable (or not) your sleep is. 

So, if you’re wondering whether your body weight dictates that you need something soft, firm, or somewhere in between, in this guide we’ll break it all down for you. 

Why body weight matters when choosing a mattress 

By now, we understand that mattresses aren’t one-size-fits-all. There are different types of sleepers that need different things to help keep them supported and as such, what’s right for you won’t necessarily be right for your next-door neighbour, let alone the entire population of the UK.  

Your weight affects how much pressure you put on the mattress, how deep you sink in, and whether you get enough support in the right place. Choose the wrong one, and you could end up with back pain, poor sleep, or a mattress that wears out way too quickly. 

So, let’s get into it! 

Best mattresses for lighter sleepers (under 9st / 57kg) 

If you’re on the lighter side, you won’t sink as much into a mattress. That means: 

• A softer mattress will give you proper cushioning, keeping you comfy in bed. 

• Memory foam or hybrid options are great because they contour well to your body. 

• Medium-soft to medium-firm (around a 3-6 on the firmness scale) is ideal. 

Avoid: Very firm mattresses — they won’t have enough give, so you’ll feel like you’re sleeping on a plank! 

Best picks: 

• Memory foam mattresses – Soft and contouring. 

• Hybrid mattresses – A good mix of support and comfort. 

• Pocket spring mattresses with a plush top – Adds extra softness. 

Best mattresses for sleepers with an average weight (9-16st / 57-101kg) 

If you fall into this category, you’ve got the most flexibility when it comes to mattress choice. Lucky you! Here’s what to keep in mind: 

• A medium-firm mattress (5-7 firmness scale) usually offers the best balance of comfort and support. 

• If you sleep on your side, a slightly softer option will cushion your shoulders and hips. 

• If you sleep on your back or stomach, go for a firmer mattress to keep your spine aligned. 

Avoid: Anything too soft if you sleep on your back—it won’t give you enough lumbar support. 

Best picks: 

• Hybrid mattresses – Best of both worlds (foam + springs). 

• Pocket spring mattresses – Great airflow and support. 

• Medium-firm memory foam – Perfect for contouring without sinking too much. 

Best mattresses for heavier sleepers (Over 16st / 101kg) 

If you’re in this range, you’ll need extra support to prevent sinking too deep into the mattress. Here’s what works best: 

• A firmer mattress (7-9 on the firmness scale) will keep your spine aligned. 

• High-density foam or reinforced pocket springs help with durability. 

• A thicker mattress (at least 25cm) is better for long-term comfort. 

Avoid: Soft mattresses—you’ll sink in too much and lose support, leading to back pain. 

Best picks: 

• Firm hybrid mattresses – Durable and supportive. 

• Orthopaedic mattresses – Designed for extra lumbar support. 

• Latex mattresses – Naturally firm and long-lasting. 

Pro tip: If you share a bed and your partner is lighter, consider a zip and link mattress so you both get the right level of firmness! 

Final tips for choosing the right mattress 

Consider your sleeping position too. Side sleepers might need a little more softness to cushion those pressure points on joints like hips and shoulder. Back and stomach sleepers will need some extra support to keep their spine properly aligned. 

When shopping for a new mattress, it’s best to start by thinking about your own needs first. If you’re a lightweight side sleeper who tends to get hot during the night, there’s a mattress out there that’s perfect for you. And equally, if you’re a heavy-set stomach sleeper who runs cold, there’s another (albeit completely different) ideal mattress out there that will tick those boxes. 

Interested in learning more about the type of mattress you need? Why not pop into your local Bensons for Beds store? One of our friendly sleep experts will be on hand to guide you through your options. And, we’ve even got our clever SleepPro technology that can analyse your sleep position and body weight to give you mattress recommendations. Win-win.