How to Make a Firm Mattress Softer

By Caitlin Giddings

Apr 27th, 2023

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Is your mattress too firm for your comfort? We’ll walk you through how to make that firm mattress softer and more to your preferences.


Even if you’re seeking a mattress that provides plenty of firm support for sleeping on your stomach or back, it can be easy to overshoot the mark. No one wants to buy a mattress imagining soft, pillowy relief—only to spend the night feeling like they’re balled up on a hardwood floor.

But that doesn’t mean you’re stuck sleeping on a hard slab. Here’s how to make your mattress work if it’s too firm for you. (And if you’re not sure if it’s too firm, here are five ways to know.)

Break In Your Mattress

Mattress experts advise you spend at least 30 days to break in your new mattress—and even longer, if it’s made from memory foam—before you make any rash decisions about replacing it. This might sound like a long time to sleep on something that doesn’t feel comfortable, but you need this crucial period for your body to adjust to the mattress, and the mattress to adjust to you. If you want to speed things up a bit, you can walk or crawl around on the mattress to put more pressure on it and loosen up some of its materials. Here are some more tips on how to break in your mattress.

Buy a Mattress Topper

The best way to overhaul the firmness of your mattress without replacing it outright is to add a mattress topper, or an extra layer of cushion made of memory foam, gel, latex, or other materials. There are mattress toppers for almost every nighttime need: to ease back pain, to make your bed cooler, to make your bed warmer, or to add an extra layer of plushness. Heck, you can even buy a mattress topper to make your bed more firm. If loosening up a firm mattress is your priority, there are loads of options for soft mattress toppers that can do the trick.

Here are a few of our favorites:

  • Our pick for hot sleepers is the budget-friendly Zinus mattress topper, which has a green tea and charcoal infusion that wicks moisture and keeps you cooler at night. You can choose from three memory foam thickness options to get the level of softness you need.
  • The higher-end Leesa memory foam topper is a two-inch layer of foam with a soft, ultra-plush feel that springs back into place quickly after you roll off of it. It’s ideal for side sleepers who need more cushioning under their pressure points.
  • Casper’s latex and foam mattress topper is great for those who aren’t sure what they’re looking for because its medium-soft feel works for so many types of sleepers. The only downside is that it doesn’t have a removable cover for washing.

Change the Foundation or Bed Frame

A mattress foundation is the supportive base beneath your mattress, and can take the form of a box spring, platform, slatted bed frame, or other system. The makeup of this foundation can have a big impact on the height, airflow, durability, and overall feel of your bed. If you have an innerspring mattress, adding a box spring foundation can make the bed feel softer because it absorbs some shock.

If your mattress is made of memory foam, however, this trick won’t work to offset firmness because you need to use a more solid foundation like a platform or bed frame. Instead, you might try our next option.

Crank Up the Heat

Memory foam actually softens in warmer temperatures and firms up in the cold, which is why it’s so great at adapting to your body’s contours.While we always recommend sleeping in a cool room, if your mattress feels too hard in the winter months, try adjusting the thermostat to see if making the room toastier helps. With luck, you won’t have to keep the heat high every time you sleep on the mattress—the added warmth will just hasten the breaking-in process.

Exchange It for a Softer Mattress

There’s a reason so many mattress brands offer generous sleep trial periods. If after the 30-day break-in period your mattress still feels too firm, swap it for something that works better for you. Most companies will allow you up to 100 days to do this; some even offer up to a year, with free returns included. Check the trial period for your mattress and exchange it if you just can’t make it work. The improvements you’ll see in sleep quality and overall health will be worth the hassle.

Check out our guide to returning a mattress so you can avoid some headaches during the exchange process.