Can I make my mattress firmer instead of buying a new one? Yes, you can. Here's how

This is how to firm up a soft mattress for a better night's sleep

pink and blue bedroom with striped wallpaper and large bedside lamp
(Image credit: Future PLC / Mary Wadsworth)

Q: I have a soft mattress and think it might be giving me lower back pain. Can you make a mattress firmer or do I need to replace it?

This was an email I received recently, and I'm pleased to say that it's surprisingly easy to make a mattress firmer. We've spoken to sleep specialists to uncover the best steps to take if you think your too-soft mattress is keeping you up at night.

The current Presidents' Day mattress sales are of course a brilliant opportunity to make savings if your mattress has simply seen better days. Because even the best mattresses don't last forever – as we found out when we asked experts how often you should replace your mattress.

Can I make my mattress firmer?

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(Image credit: Future PLC / Paul Raeside)

A quality mattress isn’t just the difference between a good night’s sleep and feeling a little groggy the next day. It’s the difference between enjoying good overall mental and physical health and potentially struggling with health and performance challenges in the longer term, as sleep specialist Thomas Høegh Reisenhus from TEMPUR (opens in new tab) points out. After all, we spend around 26 years of our lives sleeping.

Invest in a firm mattress topper

Buying one of the best mattress toppers (not to be confused with mattress protectors) is the easiest and most cost-effective way to add extra firmness to a softer mattress, says Theresa Schnorbach, Sleep scientist from Emma - The Sleep Company (opens in new tab). 'The right kind of topper can help to add another layer to help distribute weight more evenly and stop that "sinking in" feeling that you can often get with a softer mattress; ultimately helping to better support you as you sleep.'

You can buy mattress toppers that are designed to make a mattress firmer, and there are also options with a firm and soft side to suit the needs of different sleepers.

John Davies at Avocado Green Mattress (opens in new tab) comments that purchasing a firm topper is a popular solution for customers facing this problem. For a quick fix, there are inexpensive options, at Amazon (opens in new tab).

Avocado Organic Latex Mattress Topper | was $649.95 (opens in new tab)

Avocado Organic Latex Mattress Topper | was $649.95, now $584.10 at Avocado (opens in new tab)
Avocado are running 10% off sitewide, so you can save nearly $70 on the best organic mattress topper on the market.

sleep expert Theresa Schnorbach from Emma
Theresa Schnorbach

Theresa Schnorbach is a psychologist and sleep scientist, specializing in Clinical Psychology and Cognitive Neuropsychology. She has completed post-graduate training in Cognitive Behavioural Therapy for Insomnia (CBT-I) with the German Sleep Society (Deutsche Gesellschaft für Schlafforschung und Schlafmedizin (DGSM), endorsed by the European Research Society.

Choose a latex topper at least 3in thick

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(Image credit: Future PLC)

Jin Chon, Co-Founder of Coop (opens in new tab) agrees that you can firm up a soft mattress with a topper, and specifically recommends opting for a latex one. 'Latex is a great topper material since it tends to have more support,' she begins. 'Latex is a material that you would sleep "on" vs. memory foam which sinks.' 

Jin assures that either will still help, as it will spread the weight on the top of the mattress and prevent the pressure points from sinking in. 'A thicker mattress protector is better than a thin one,' she adds. 'Think 3 inches or thicker.'

Tempur-Adapt Topper | was $419 (opens in new tab)

Tempur-Adapt Topper | was $419, now $251.40 at Tempur-Pedic (opens in new tab)
Bringing Tempur-Pedic comfort at the fraction of the cost, our favorite mattress topper is 3" thick and now 40% off, saving you $167.60. 

jin chon co founder of coop
Jin Chon

Jin Chon is the co-founder of bedding company Coop, which sells pillows, bedding, pet beds. In October 2013, Coop released the first Coop pillow, and the company has been building a collection of best-selling sleep products ever since.

Check the foundations

It could be that your mattress is fine and that your bedframe is causing it to sag. If you have a box spring bed, sleep expert Hafiz Shariff at Owl + Lark (opens in new tab) suggests checking for signs of wear such as squeaking, sagging, or broken slats. If it's in good condition, try adjusting the bed frame to make sure it's level and supports the foundation evenly. 

Hafiz points out that a bedframe can become loose and move over time. If the foundation is worn out, you may want to consider replacing it with a newer, sturdier one that can provide better support. Think about how much to spend on a mattress to get the best possible support.

expert image
Hafiz Shariff

Hafiz Shariff is a sleep expert and founder of mattress and bedding company Owl + Lark. He has extensively researched human circadian rhythms and coined the term 'circadian fitness'.

Flip it over

'Over time, the materials in your mattress can compress and break down, making it less supportive,' comments Hafiz Shariff. 'Flipping or rotating your mattress can help redistribute the materials and restore some of the firmness. 

If you have a mattress that's designed to be flipped, be sure to slip it over and rotate it from head to foot every few months to help prevent uneven wear.

Place a plywood board under your mattress

Put a plywood board (available at Amazon) (opens in new tab), under your mattress to help make it firmer. It just provides a solid, flat surface for the mattress to rest on. 

Hafiz Shariff says to measure the thickness of your mattress and choose a plywood board that is thick enough to provide the support you need. Then, place the board between the mattress and the foundation, making sure it's evenly distributed and centered under the mattress.

bedroom with wooden bedside unit and blue wood panelling

(Image credit: Future PLC / Anna Stathaki)


What happens if your mattress is too soft?

Thomas Høegh Reisenhus, sleep specialist and sleep counselor at TEMPUR says your mattress should adapt to you, distribute your weight evenly, keep your spine straight, and absorb pressure to aid comfort and relieve pain. 

'A mattress that is too soft will cause your back or hips to slouch and your spine to fall out of alignment,' he explains. 'A mattress that is too firm will put too much pressure on your joints, potentially causing discomfort or pain.'

What are the signs your mattress needs replacing?

Sleep scientist Theresa Schnorbach says that if you try a firmer topper on top of your mattress but continue to experience discomfort due to improper spinal alignment while you sleep, it's time to replace your mattress for something that better suits your needs.

A mattress that is worn out or has lost its support will need replacing, particularly if you're experiencing pain or discomfort while sleeping, or waking up with aches and pains. Read up on how to buy a mattress and go in store for reassurance before investing.

Millie Hurst
Section Editor

Millie Hurst is Section Editor at Homes & Gardens, overseeing the Solved section, which provides readers with practical advice for their homes. She has been in the world of digital journalism for six years, having previously worked as Senior SEO Editor at News UK both in London and New York. She joined the Future team two years ago, working across a range of homes brands. Millie formerly worked as Senior Content Editor at Ideal Home, taking care of evergreen articles that help and inspire people to make the most of their homes and outdoor spaces. Millie has a degree in French and Italian and lives in North London.