How To Fix A Sagging Mattress

Updated on April 1, 2023

Sleeping on a supportive mattress can help promote a good night’s sleep. A mattress should support your back and keep you comfortable throughout the night. One of the things that can disrupt your sleep is a sagging mattress. Unfortunately, buying a new one can cost a lot of money, especially considering that some can cost over $1,000.

Though it’s a high-ticket item, it is something that you would need to invest in. But what if you are running low on cash and your mattress starts to sink in the middle or even the edges? There are a few tricks that you can do to keep it comfortable in the meantime. Let’s take a look at some of the options:

Check The Warranty

Before we dive into any home DIY solutions, the first port of call is to check your warranty.

Most mattresses come with lengthy warranties. If you purchased something online within the past 10 years, there’s a chance that it may still be within warranty. For example, most memory foam mattresses from reputable brands come with 10+ years, while latex options are usually 15 years and above.

If your particular purchase is still with a warranty, check the terms. Some companies will offer a replacement if the mattress has been cared for properly and if the indentations are within a certain depth. If in doubt, contact the retailer in the first instance.

Using a Mattress Topper

Sleepez latex topper
Sleepez Roma latex topper

One of the cheapest alternatives when it comes to buying a new mattress is using accessories such a mattress topper to fix sagging. It can give you far more additional support that the mattress already lacks when it comes to small to medium-depth indentations. Toppers are a versatile solution that can help rejuvenate all types of mattress materials and fix numerous issues too.

Though it’s cheaper than buying a new mattress itself, you also have to take a closer look at its price. Toppers for a King-sized bed can cost as much as $150, and latex toppers can cost even more. There are cheaper ones like memory foam toppers, for example, that you can pick up for around $25. They can somewhat alleviate the sagging, but these will most likely not be as supportive and begin to fall into the sag within a year or so.

Generally, most mattress toppers are around 1-4 inches thick. So that’s an additional height for the mattress. It means that you might need a bigger bed sheet to prevent the mattress topper from moving around.

Many people buy a topper even when their mattress isn’t sagging. When they feel that the mattress is too firm, a soft topper can add comfort to their backs when they sleep at night. Alternatively, a soft mattress can be made firmer with a firm topper.

Other individuals tend to buy a mattress topper for its ability to regulate temperature on top of the fact that it can get rid of the sagging part on your mattress. Many of these mattress toppers nowadays are made of memory foam infused with gel or copper, among other cooling materials. These are very effective at keeping the sleeper cool at night, while also fixing a sagging mattress at the same time.

Using Pillows

Using pillows isn’t the ideal solution. It will not fix the issue. However, if you’re a side sleeper and notice sinking in the center of the mattress, try using a cheap microfiber, feather, or relatively low pillow. Place the pillow under your leg and sleep closer to the edge of the bed. That way you’ll be supported from falling off the edge, and you can avoid the sagging center a little. You can also place the pillow in the middle area where the sinkage is, but this may not go down too well with your partner.

Flipping The Mattress

mattress flipping
Flipping a mattress over

Another old school trick when it comes to dealing with your saggy mattress is to flip it. Most mattresses prior to the 2000s were flippable, but this isn’t always the case with modern mattresses. This method typically works on an innerspring mattress, simply because the construction is the same on both sides. Even innerspring mattresses nowadays may not be flippable, so check with the manufacturer to be sure.

If you have a foam mattress that’s sinking, flipping it may become even less of a possibility. It’s highly unlikely that a foam mattress would be flippable. That’s because the multiple layers of foam are arranged in such a way that mattress flipping will deem it unusable. However, some mattresses are marketed as 2-sided and so are flippable, but the chances are that it will be a different firmness level on the flip side, thus changing the comfort level.

Unfortunately, flipping a mattress to fix sagging isn’t as straightforward as it used to be.

Rotating The Mattress

One of the most common questions we get regarding old mattresses is “how to fix a sagging memory foam mattress?” In our opinion, it’s by rotating it. However, this solution isn’t restricted to memory foam mattresses.

If the mattress flipping method isn’t an option, what you can do is rotate the mattress 180 degrees. So, your weight will then be redistributed on parts that you haven’t used that much. For example, the most prone areas to sagging are around the upper body and midsection of the sleeper’s body, and the least affected are the legs and foot area. If you rotate the mattress 180 degrees, these indented areas will then be placed at the previously less affected foot area, and you’ll end up using this fresher section to support your upper body and midsection. Note, that this is also an effective method for dealing with back and hip pain relief.

The mattress rotating method is one of the better options and should be done every 6 months to prolong the mattress’s lifespan. It can be used to restore all types of mattresses, but realistically when the mattress begins to sag too much, even rotating it will not offer much support.

Adjusting The Slats On Your Bed

sagging-mattress bed slats
Adjusting the space between slats

If the tricks we’ve already mentioned don’t work, you will have to check your bed frame. There are instances when a slatted bed is causing the mattress to sag. Maybe the slats are spaced too far apart. If so, you can adjust the distance between each slat. The closer each slat, the more support that it can deliver to the mattress and the less it sinks in the long term.

Perhaps, you can even change the bed frame completely. This way, future mattresses that you buy will also have more support.

How To Fix a Sagging Mattress With Plywood

How to fix a sagging mattress with plywood
Two pieces of large plywood

If you don’t have the budget to buy a new bed frame or box spring, you can place a sheet of plywood and position it underneath the mattress. A large piece of plywood enough to cover the whole area of the mattress/bed surface is ideal, but you may not be able to get a piece that size as a whole sheet. Cutting the wood into two and placing it between the mattress and bed will be fine. The thickness shouldn’t matter too much, but ideally, it should be at least 0.5 inches thick. Now, this can give you additional support and may fix the sagging in your mattress. However, you might also feel the mattress feel a bit firmer.

Why plywood and not MDF or some other material? Well, plywood, especially marine plywood, is very tough and not susceptible to warping as much as other wood, especially when faced with moisture such as sweat and certain bacteria. It can withstand humidity and fungal attack better than other types of easily available wood.

Using plywood is a great option, especially if you already have some unused in the shed. Even so, buying enough from a hardware store to cover a Queen size bed shouldn’t cost too much.

When Do You Need to Buy a New Mattress?

These temporary solutions can get your mattress by for a short while. However, there are instances when no amount of flipping, rotating, and plywood can compensate for wear and tear. To give you an idea about when to buy a new mattress, here are some signs that call for a new one.

One, if you see springs poking out, then it is already time to change the mattress. This is a common problem among innerspring mattresses. It is common to see this when you have a child who would jump around the mattress whenever he or she is horsing around.

Next, if you start seeing noticeable deep indentations on the surface, it’s about time to say goodbye to the old mattress. If it’s 1.5″ deep, expect that it won’t get fixed by any of the remedies that we have mentioned. The warranty is also unlikely to honor such deep sagging. It is possible that you’ve failed to rotate the mattress every once in a while or you are heavier than what the mattress was designed for. In this case, the mattress no longer provides enough support to your spine and hips.

And lastly, if your mattress is over ten years old and you already feel body aches every time you wake up in the morning, it’s time for a replacement.


Getting a new mattress can cost a lot of money. There are instances when you can’t save your mattress anymore and need to buy a new one. However, with proper care and some ingenuity, extending its life and even making it more comfortable once it starts to sag is possible.

But of course, easy DIY steps can only do so much. If you find poking springs or indentations on your mattress, it might be a good idea that you find a new one. This way, you don’t end up sleeping with backaches by morning or in the middle of the night.