Best Side-Sleeper Mattress 2025: Picked by a Sleep Science Coach

If you’ve ever tried to consciously change your sleeping position because of something like a medical procedure, you know how hard it is to fight your natural inclinations. The good news for side sleepers is most experts agree that sleeping on your side is at least as good as any other position.

Sleep experts at Houston Methodist say side sleeping has “the least negative impact on health.” Things worse for you include not sleeping enough or sleeping in any other position—namely, back sleeping. Sleeping on your back is the “worst position” according to the Mayo Clinic, which calls side sleeping “a good way to sleep.”

Testing mattresses isn’t a one-and-done situation, where we sleep on it once before giving a full evaluation. Good things take time, after all, which is why we spend a week or more on each mattress we test. We track our sleep patterns with sleep trackers and record that data to see how we fared with each mattress.

The short answer is: the firmest you can go while remaining comfortable.

The long answer is that many side sleepers gravitate toward a soft mattresses, which usually means medium-soft memory foam. But it’s important to be sure you have a mattress with enough support or even extra support in key areas like the lumbar zone. Pay close attention to the firmness level the company advertises and take your body type into account, as the more body weight you have, the firmer the mattress you’ll want.

One other thing worth considering is that it’s easier to make a mattress softer with a topper. If you’re spending a lot of money on a high-quality mattress made with good materials and you feel it’s too firm, it’s relatively cheap and easy to add a mattress topper, since almost every topper has the effect of softening your sleeping surface. However, you can’t make a mattress firmer—if you found a firm mattress topper and put it on a soft foam bed it would still have a squishy base, which would lead to sinkage and likely pull your back out of alignment. So our advice as a mattress testers is to always error toward too firm.

Mattress toppers often give you that “new bed” feel at a fraction of the price and can help correct issues with a mattress you generally like.

For side sleepers, pairing a very supportive firm mattress with a cushy topper is often just the right blend of softness and support. If you only take one piece of advice from this article, it’s that you should always buy the firmest mattress you think you can tolerate and then soften it up with a topper if you have issues.

Side sleepers should stick with hybrids in most cases. Given that you’re putting more weight on a smaller surface area you might think that memory foam is nicer than a hybrid mattress that has a layer of springs (often called coils), imagining that memory foam allows you to sink into a fluffy little cloud.

The problem is that when you’re sleeping well and not moving much, over the course of a night, that foam will slowly compress under you. If it’s just one layer of foam, after a while it will feel like you’re sleeping on a yoga mat. That’s why mattresses with multiple layers of foam of various weights are better, and it’s why we like hybrids better yet. That layer of springs means the foam doesn’t compact nearly as much, in our experience.

A good hybrid gives you a chance to sleep for a solid six hours without needing to change position, which isn’t necessarily the case for most sleepers on an all-foam mattress. Hybrids also tend to sleep cooler because there’s less mass of solid foam absorbing heat throughout the night.

We work with many mattress brands, which are constantly dreaming up new models to meet consumer needs. The bed-in-a-box mattress business has exploded since the pandemic, and there are always new brands to test. We are always researching the landscape and looking for new mattress companies to investigate.

Typically, brands will send our team samples so that we can test them. We will then give them away while securing no personal benefit from their rehoming. (No, you can’t even buy us a beer.) When a mattress company declines to send us a sample or doesn’t respond but we believe readers want our unbiased opinion of the product, we will purchase and expense the bed.

Everyone needs to sleep. So when testing is complete and we have everything we need to give a comprehensive report, we give back to our local communities. Students, families, young couples—whoever needs a mattress, we do our best to get it to them. We do this through the grapevine, Facebook Marketplace, Facebook Buy Nothing groups, and even Nextdoor listings.

It may seem like a bunch of gibberish, but there are important terms to keep in mind while mattress shopping. Pressure relief describes whether a bed is able to keep tension off of more sensitive areas of the body, like the hips or shoulders. These areas are also known as pressure points and require heightened softness. Durability is another term that refers to how well materials hold up. Edge support determines how well a bed supports you on the outer edges, whether you’re sitting or lying on them.

CertiPur-US is the most important one when it comes to memory foam. It’s third-party verification that your mattress isn’t holding potentially harmful chemicals. Other certifications authenticate whether a product was tested by a third-party lab, is truly organic, or passes a certain test for health and safety standards.