How to Fix a Sagging Mattress – 5 Proven Strategies

A sagging mattress is no joke.

Because sleeping on an uneven mattress can cause a range of heath complications such as joint pain, muscle aches, and excessive tiredness due to reduced sleep quality.

And if you continue to ignore the often minor initial discomfort – then you could end up with much more serious issues such as spinal disc problems, nerve pain, and chronic discomfort.

That’s why I’m going to show you how to fix a sagging mattress using 5 different tried and tested strategies.

Alternatively: if your mattress is beyond repair, replace it with one of the top 10 anti-sag mattresses so that you can get a comfortable night’s rest.

5 Ways to Fix a Sagging Mattress

The 5 best ways to fix a sagging mattress are to buy a new mattress, buy a new frame, add mattress support, use a mattress topper, or file a warranty claim to get a repair/replacement.

More details below:

1: File a Warranty Claim

If your mattress is still under non-prorated warranty then you might be able to get a new one without any great additional expense (shipping costs may be required).

However, the sagging must typically be quite significant in order to make a successful claim – usually needing to meet specific measurements in order to qualify as being defective.

Many of the mattress warranties that I’ve looked at stipulate that the mattress must indent by 0.75 to 1.5 inch or more but you’ll need to refer to the warranty for your mattress to find out the exact specifications in your case.

But in almost all cases, a warranty will not cover natural softening or dissatisfaction with the mattresses’ comfort – so you’ll not be successful if the precise depth changes are not met.

However, if your mattress is covered by the sleep trial, you should be able to return it.

Usually, you’ll have to take pictures of the sagging in a way that illustrates how the depth changes are met or exceeded to file a warranty claim.

Make sure that you read the wording to see if you’ve done anything that voids the warranty – such as using an incompatible foundation or the wrong type of support legs.

Finally, be sure to check if the mattress falls under a prorated or non-prorated warranty – some mattresses will often be split between the two. For example the first 5 years may be non-prorated, whilst the final 5 years of the 10 year warranty may be prorated.

The difference is that a non-prorated warranty will not typically cost you anything other than shipping and handling to have the defective parts replaced – whilst a prorated warranty will require you to pay a percentage of either the original cost of the mattress or the parts that need replacing.

2: Buy a New Mattress

No luck with the warranty?

Then the next option would be to look at buying a new mattress.

I would especially consider looking into getting a new mattress if your old one is more than 5 – 7 years old, has a permanent indent of 1 inch or more, and/or is very uncomfortable – rather than spending money on a new topper or pad.

To limit sagging in the future, consider buying mattress that won’t sag prematurely.

3: Buy a New Base

Is the sagging due to a problem with your bed frame rather than the mattress?

If the issue is something as simple as a broken slat or loose joint then the best option is to either fix the issue – or buy a brand new compatible base if it’s beyond repair.

One of the giveaways that the sagging is the result of an issue with the frame is if the bed is making a noise – in which case you should remove the mattress and take a closer look underneath.

If it is the frame – then be sure to once again check out the warranty to see if you can get a replacement without having to buy a new one.

4: Add Mattress Support

If you’re looking to fix your mattress without buying a new mattress or frame then there are a range of temporary solutions that can work by attacking the issue from ‘beneath’ using the following DIY strategies.


A very simple way to fix your saggy mattress is to shove a bunch of pillows under the spot where the mattress is dipping.

Memory foam and latex pillows typically have good shape retention and may do the job better than regular pillows.


Don’t have any spare pillows lying around?

Then if you’re a bit of a DIY enthusiast, cutting a sheet of plywood and fitting it over the slats could be a decent temporary fix.

If you do this however, just be aware that the wood can block airflow and trap moisture – which could cause you to sleep hot or even trigger mold growth.

Use a Box Spring

A better alternative to using plywood might be to switch to a box spring base.

If you’re already using a box spring, be sure to check that the sagging isn’t a result of a defect with the frame or the springs.

Try Other Supports

Other strategies for increasing the support beneath your mattress include adding a layer of medium to high density memory foam, or purchasing an air bladder to target smaller areas of sagging.

Flip or Rotate the Mattress

Finally, flipping or rotating your mattress may be enough to fix the problem because it will change how your weight is distributed across the mattress.

Just be aware that many memory foam and hybrid mattresses cannot be flipped because they use a one sided, layered structure.

5: Use a Mattress Topper

If you can’t fix the problem from the bottom – then you might be able to add a mattress topper or pad to the top of your mattress to cover up the sagging.

Mattress toppers basically add an additional layer to your mattress to provide extra cushioning and support. There are different types of filling available – such as memory foam, feather, or synthetic fibres.

You’ll want to go for the thickest mattress topper to help rejuvenate your saggy mattress – up to 7.5 cm should do the trick.

Common Sagging Mattress Questions

I’m now going to round off this article by answering some of the most common questions regarding mattress sagging.

This should help you realise how a busted up mattress can affect your sleep, how to prevent mattress sagging in the future, and more.

What is a Sagging Mattress?

A sagging mattress is one that has an uneven surface and doesn’t support the body evenly.

If you sleep alone, you’ll typically find that the mattress will dip on the middle of the bed, possibly more in areas where there’s increased pressure points – such as where your hips and shoulders connect with the material if you’re a prominent side sleeper.

If you sleep as a couple, then you may find that your mattress develops a ridge or ‘high spot’ in the middle of the mattress due to the infrequent use of the middle part of the bed.

This phenomenon tends to affect king and queen sized beds with significant padding and usually doesn’t go away with time.

What Causes a Sagging Mattress?

So, why do mattresses sag in the first place?

Well the first thing to realise is that all mattress types are susceptible to sagging – that includes foam, memory foam, latex, gel infused, hybrid, and traditional innerspring mattresses.

And one possible trigger is too much weight being placed on the mattress relative to its thickness.

So if you’re a heavier sleeper resting on a mattress that’s less than 10-12 inches thick then you may find that the mattress begins to sag sooner. Taller heights may be more beneficial for you.

Similarly, a lack of firmness can result in sagging.

For example, if your memory foam mattress is too soft for your weight and you find yourself touching the core support layers beneath then the mattress may indent faster.

And the type of core support itself can be a factor too.

With sprung cores, for example, sagging can arise as coil tension decreases over time and the padded upholstery layers begin to drop – resulting in a lumpy looking mattress that feels like lying on Duplo blocks.

A hybrid or innerspring mattress with a low coil gauge may be able to provide more support and help combat premature sagging.

And finally, using an unsuitable foundation or inferior quality frame can increase the rate at which the mattress indents and cause sagging.

How Does a Saggy Mattress Affect Your Sleep?

Mattress sagging can be more harmful than you might think.

One of the biggest problems in that of increased pressure on your spine and joints – potentially leading to back, neck, hip, and shoulder pain.

In other instances, a poor neck or head position as the result of a sagging mattress can result in awkward breathing – possibly causing you to wake up due to restricted airways or trigger snoring.

Also, when a memory foam or hybrid mattress sags, the cooling properties are typically lessened because the airflow is impeded by the compression of the material.

Finally, a worn mattress with a sprung core can result in more noise and less motion isolation.

In all cases, a sagging mattress can result in a worse night’s sleep and ruin your energy levels the next day.

How Do You Prevent Mattress Sagging?

Preventing a sagging mattress starts with choosing the right level of support and firmness for your body weight and sleeping position.

For example, firmer mattresses tend to be better for back and front sleepers because it will help to keep your hips in the correct alignment – whereas choosing a mattress that’s too soft and has insufficient support can actually cause back pain and exacerbate mattress sagging.

You’ll also want to ensure that the mattress is placed on a compatible base and that there are no uneven gaps below the mattress that could increase pressure points.

Rotating or even flipping your mattress every few months can also help to stop sagging because it will distribute the cumulative load that the mattress is exposed to over time more evenly.

And finally, using a mattress topper or pad can potentially increase the lifespan of your mattress.

What Are the Best Mattresses that Won’t Sag?

As I said earlier – all mattresses are liable to sag over time.

However, there are certain types of mattresses that may be more resiliant to sagging.

If you’re buying a memory foam mattress, then you’ll want to look for higher density foams – whilst latex can increase longevity even more.

Innerspring mattresses are actually the type that are most prone to sagging – so picking one with a lower coil gauge to avail of a thicker and more resilient spring construction could work well for you.

Alternatively, you might like to take advantage of a hybrid mattress with a sprung layer with a high coil count and low coil gauge – but with a comfortable top layer.

Click the button below to see some of the top mattresses that are less likely to sag.

Image Attribution and Licencing

Main image: ‘Grey and Blue Bedding on Bed in Spacious Bedroom Interior With Ladder and Plant’ by Katarzyna Bialasiewicz – used with permission under the terms of Canva’s One Design Use License Agreement.