If you share your bed, this is the one type of mattress that will actually help you sleep through the night

I share a bed with my husband, which is lovely. But it’s also frustrating. I’m an early bird, he’s a night owl, which means just as I’m entering deep sleep, he’s coming to bed and disrupting it.

After retesting out top five best mattresses of the year, I’ve come to realise that there’s one type of mattress which is the answer for couples struggling to sleep. And I think it could save you from sleep divorce.

The solution is investing in one of this year's best memory foam mattresses we've tested. Luckily, the Black Friday mattress deals mean top foam beds are at their lowest prices. But why foam? Let me explain…

What is motion isolation?

Motion isolation refers to how well a mattress absorbs movement and stops it from traveling to another area of the bed. Think of those traditional innerspring mattresses where you’re practically bounced off the bed when someone else sits on it — that’s poor motion isolation.

And the springs are usually responsible. Designed to be responsive, they compress and release beneath your weight, creating that ‘bouncy’ feel.

More modern mattresses, especially the best hybrid mattresses we’ve tested this year, use individually wrapped coils to stop the movement from traveling across them — however, they will still always be more bouncy than memory foam mattresses.

Why a memory foam mattress suits couples

Foam beds absorb motion. The dense material means it doesn’t immediately spring back into shape when you move, which stops the mattress from transferring motion.

This gives memory foam mattresses a stable feel.

When I swapped from a cheap spring mattress to a foam bed, I didn’t even notice my husband getting into bed. When I woke in the night to find him next to me, I was genuinely surprised.

The best motion isolation we’ve ever tested

Our new mattress testing methodology includes both subjective and objective ways to measure motion isolation.

To gauge the subjective motion isolation score, we gather feedback from our expert panel of mattress testers as well as the lead tester’s 3-week sleeping experience.

We then perform a slam ball test. This means dropping a 5kg weight onto the mattress and using an accelerometer, we measure the impact of the ball (the motion absorbed) and how long the motion continued on the mattress.

One mattress in particular came out on top: The Siena Signature.

With an impressive 4.5 out of 5 score (the best motion isolation we’ve ever seen) we think it’s in the running for being one of the best mattresses couples can buy. But why is this?

Well the firm foam almost immediately stopped motion from traveling on the bed. In fact, when we lay on it next to another tester, we could barely feel them move at all.

And, when we performed the slam ball test, it only took 1.14 seconds for movement to stop after the ball was dropped. For context, our best cooling mattress of the year, the Bear Elite Hybrid, incorporates coils in the build and it took a full 3.5 seconds for movement to stop. That’s over double the time of the Siena. Read our full Siena Signature mattress review for its full performance.

3 more things to look for in a foam mattress for couples

If you’re choosing a memory foam bed in the mattress sales, there are a few more things you might want to look out for.

Decent edge support

Edge support refers to how stable the perimeter of the mattress is. This isn’t only important for tasks like getting ready or sitting on your bed, but also for maximizing the amount of space in your bed to sleep on.

There’s nothing worse than a mattress with edges that collapse. One mattress my husband and I tested forced us to sleep in the middle of the mattress because of how soft the outside of the mattress was — cue tired, groggy and grumpy mornings.

Generally, hybrid mattresses have better edge support because of the coils, especially if they have a reinforced perimeter. For example, during our testing for the Saatva Classic review, we awarded this luxury hybrid a 5 out of 5 for edge support.

However, that’s not to say memory foam mattresses can’t be supportive. In fact, the Siena Signature scored a 4 out of 5 in our retesting for edge support — proving its excellence. For a foam bed, the best way to tell how good the edge support is is through reviews. Check out all of our mattress reviews to find out more.

Cooling tech

It used to be said that memory foam mattresses trap heat. And, while that does remain true for some cheaper foam beds, there are ways around this.

If you or your partner sleep particularly hot, choose memory foam mattresses that incorporate specialist cooling materials. These include:

Phase change material: This material moves heat away from the body. This stops it from building up beneath you in the mattress, and helps it dissipate quickly.

Glaciotex: This material is usually found in the cover of cooling mattresses. It has a high conductivity, which means it moves heat away from the body. It also has a cool-to-touch feel.

Copper foam: Metal particles are added to foam to increase conductivity, and help move heat away from the body.

Pressure relief

Memory foam mattresses excel at pressure relief. This means the ability of a mattress to distribute your body weight evenly across the bed to stop pressure from building in your joints. This is particularly important for side sleepers who often struggle with pressure in the shoulders, hips and knees.

You can have all the advanced features of a perfect mattress for couples, but if you both aren’t comfortable, it won’t be worth it.

Good pressure relief comes from a balance of a strong support core and quality comfort layers. For foam mattresses, this usually means a more dense, firm foam core with more plush layers that cushion the body.

Consider firmness here, too, and how your needs can differ depending on sleep position.

Stomach sleepers will likely benefit from a firmer bed (8-9 out of 10 on the firmness scale) while back sleepers will find better pressure relief in medium-firm mattresses (6-7 on the firmness scale). Side sleepers, meanwhile, tend to find medium (5-7) to medium-firm mattresses offer the best pressure relief for their sleeping position.

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