How to fix a sagging mattress when replacing it

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How to fix a sagging mattress when replacing it

Despite what manufacturers would have you believe, purchasing an expensive, high-end mattress will not fix all of your sleep issues. However, sleeping on a mattress that sags or dips in the middle can make it challenging to get a good night’s sleep.

In a perfect world, mattresses would last longer, and you’d be able to replace yours as soon as they started to sag. However, this might not always be the scenario, and you may have to put up with an old, saggy mattress for longer than you’d want. While you can’t “repair” a bed in this state, there are a few things you can do to make yourself more comfortable. Here are some ideas for you.

The mattress should be rotated (and potentially flipped)

Again, this isn’t a long-term solution, but moving your mattress to move the dips to a different location may assist momentarily. Many modern beds have a designated top side, but if yours is dual-sided, you can flip it over to the other (hopefully less sagging) side.

Locate the sagging areas

Although it’s likely evident that your mattress is sinking, you may pinpoint specific locations by placing something flat across the top of the bed and looking for gaps. Another alternative is to run your hand over the mattress and feel for bumps, dips, or other irregularities. 

Invest in a mattress topper

A soft-but-supportive mattress topper can sometimes help extend the life of a sinking mattress. Most mattress toppers are two to five inches thick and consist of foam, latex, wool, down, down substitute, or feathers. The thicker and more dense the mattress topper is when dealing with a sagging mattress, the more of a difference it will make.

Examine the base of the mattress

Even though many newer mattresses, particularly ones shipped in a box, state that they don’t require a box spring, paying attention to their base is still crucial, if wooden slats support the mattress, double-check that they are evenly spaced and that none of the slats have gone through.

If your mattress is on a four-legged bed frame, it may be suitable for a while, but it will ultimately sag in the center without anything to support it. After inspecting your bed’s foundation, decide whether it needs to be replaced or if one should be added. It’s also possible to put a piece (or two) of plywood under the mattress.


Ameer is the content director of Sleepingmentor, which means he not only reviews new mattresses, bedsheets, pillows, and mattress toppers every week, but also curates all the comparisons, best of pages, reviews pages, and vs pages on the site. He takes a straightforward, honest approach to his reviews. He covers sleep science by researching a lot on Google and finding meaningful content which entertains his users.

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