9 Signs Your Mattress Is Too Soft & You Need a Firmer Bed

If your mattress is too soft, you might sink into the surface, notice visible sagging, wake up with aches and strains, or have trouble getting comfortable at night.

A high-quality, ultra-comfy mattress is a critical component of getting a good night's rest. But the plushest option may not be the best choice—even if you like a cushy surface, there's such a thing as too soft.

Find out why mattress firmness matters, what firmness level is ideal for different sleeping styles and ailments, and telltale signs your mattress is too soft.

Why Mattress Firmness Matters

Your sleeping environment matters—from darkness and room temperature to bedding materials and noise. While your mattress is important, buying one simply based on its premium price tag or that boasts an ultra-soft, uber-plush feel may not be the wisest choice—at least, not for everyone.

Mattress firmness plays a big role in comfort and sleep quality. Beyond things like spinal alignment and pressure relief, it affects how quickly you drift off, how long you stay comfortably asleep, and the ability to get deep, restorative shut-eye.¹

The effects can go both ways too. Not getting enough sleep (say, because of an old or poorly designed mattress) impacts the ability of muscles, bones, and other bodily systems to repair and grow. It can even make you more sensitive to pain (including pain from sleeping on a too-soft mattress).^2,3

Medium-Firm Mattresses Are Ideal for Back Pain

For those with back issues—like achiness, strain, or stiffness—a medium-firm mattress might be the best option. Research shows that sleeping on a medium-firm surface (about six to seven out of 10 on a firmness scale) for just four weeks can reduce back pain by roughly 48% while boosting sleep quality by 55%.⁴

The One is a medium-firm, affordable foam mattress that was Consumer Reports’ top-rated all-foam mattress of 2025. 

9 Telltale Signs Your Mattress Is Too Soft

Is your mattress too soft? It might be if:

• You often wake up with lower-back pain
• You have a persistent hip or shoulder ache
• You often wake up with neck or upper-body strain
• You feel stuck when rolling over
• You have trouble getting in and out of bed
• You experience restless tossing and turning
• It fails the hand test
• There's visible sagging or body impressions
• You're a heavier sleeper experiencing excessive sinking

Keep reading for details.

1. You Wake Up with Lower-Back Pain

A soft mattress could result in chronic lower-back pain if you sleep on your side or stomach, as the overly plush surface could cause your hips and knees to sink down or your spine to bow unnaturally. When lying on your back, the lack of support might lead to overarching the area of your spine that curves naturally toward your tailbone.⁵

Meanwhile, a medium or medium-firm mattress can help keep everything aligned and in a neutral position so you don't wake up with stiffness or strain in your lower back.⁶

Our guide has more insight into the best and worst sleeping positions for lower-back pain.

2. You Have a Persistent Hip or Shoulder Ache

If you have unexplained, persistent hip or shoulder pain, it could be that your mattress is too soft. Without adequate support for these areas when sleeping on your side, they can sink down and leave you with achy joints in the morning (or all the time).^7,8

Sleeping with a pillow between your knees can help with hip strain, but it might not be enough to fully make up for a soft mattress with insufficient support.⁹

3. You Often Wake Up with Neck or Upper-Body Strain

If you find yourself waking up with neck pain, stiffness in your traps, or other strained muscles in your upper body, your mattress could be contributing to a misaligned spine. This might happen to stomach sleepers who unnaturally arch or twist their backs due to a lack of upper-body support or when lying on your side or face-up.^10,11

4. You Feel Stuck When Rolling Over

Not everyone stays in the same sleeping position throughout the night. But excess sinkage from a too-soft mattress can make it harder to roll over into a new position (especially without waking up).¹² A firmer surface may help with easier mobility while sleeping.

5. You Have Trouble Getting In and Out of Bed

Edge support is a reinforced perimeter on a mattress that helps minimize motion transfer while preventing you from sinking in when sitting on the edge. Not all mattresses have it, though.

No edge support, combined with a sagging center or general lack of firmness, can make it tricky to get in and out of bed without feeling like you're sinking in.¹²

6. You Experience Restless Tossing and Turning

Folks who feel like they can never get comfortable enough to sleep soundly might continuously toss and turn at night and wake up repeatedly.⁸ Research shows that a too-soft mattress can contribute to poor alignment, which can cause muscle tension and all-around discomfort, leading to more frequent wake-ups.⁴

7. Your Mattress Fails the Hand Test

The hand test can help you figure out if a mattress is too soft or firm. While lying flat on your back, attempt to slip one hand under your lumbar curve (that's the lower back, where the spine naturally curves).

If it slides underneath easily, the mattress might be too firm. But if you struggle to get your hand under your lower back, it could be too soft and lack proper support.¹³

8. There's Visible Sagging or Body Impressions

When you're out of bed and inspecting the condition of your mattress, is there visible sagging in the center? Do you see body impressions on either side? This can happen over time with normal wear, and rotating your mattress regularly can help prevent it. That said, dents any deeper than about a half-inch can signal the mattress has lost sufficient support.⁴

Learn more about how to fix a sagging mattress in our blog.

9. You're a Heavier Sleeper Experiencing Excessive Sinking

Heavier sleepers (those weighing about 230 pounds or more) generally need more support than a very plush mattress can provide.⁸ Though medium-firm models are ideal for most people, larger bodies might get more optimal sleep with a firmer mattress. The added firmness and structural reinforcement can prevent "bottoming out," when mattress materials are compressed by surface weight to the point that they no longer provide support or redistribute pressure.¹⁴

Also, keep in mind that some mattresses have weight capacities. It varies, but for instance, a queen or king innerspring model might have a weight limit of 500 pounds (or 250 per person if the bed is shared by a couple).

What Happens If You Ignore the Warning Signs of a Too-Soft Mattress?

Not having proper support while sleeping isn't really something you want to brush off. Over time, sleeping on a too-soft surface can lead to a number of problems—from chronic back pain and long-term posture issues to trouble falling asleep and reduced REM (rapid eye movement) sleep, to name just a few.⁴

Fixes for an Overly Soft Mattress

So, what should you do about it? To add support in the short term, consider getting a firm mattress topper (like something made of high-density foam) or reinforce the base with a foundation. As mentioned, rotating your mattress every so often can help prevent sagging and indents.

But when looking at the bigger picture and your long-term health, replacing your mattress with a medium or medium-firm model with balanced support and whole-body pressure relief is the way to go. You might be surprised how much better you feel day to day and in the long term simply from sleeping on the right mattress.

Your too-soft-for-comfort mattress might be eligible for a trade-out. With Casper's upgrade program, you can get 10% off a new mattress (with approved models) when replacing an existing Casper mattress you've had for at least a year. Plus you get a free Original Casper Pillow with the purchase!

Find Your Perfect Firmness with Casper

A high-quality mattress can be an investment—a worthwhile one, if you ask us, particularly if you're losing sleep or experiencing musculoskeletal issues. Besides that, getting a new mattress may seem like a logistical hassle. But Casper makes the process easy while giving you peace of mind about your purchase.

After browsing our offerings and comparing mattresses for firmness and features, you can choose a Casper mattress that aligns with your sleeping position, body size, and unique needs. Our compressed bed-in-a-box packaging is a breeze to set up on your own, but if you'd like to streamline the process, you can opt for in-home delivery and removal of your old mattress.

What's more, your purchase is risk-free, thanks to our 100-night trial. You can sleep on your new mattress for up to 100 nights, and if it's not working for you for any reason, you can contact us to arrange for a pickup and get a refund.

We also have bed pillows engineered to provide head and neck support, no matter your sleeping position. Beyond that, you'll find bed sheets, duvets, bed frames, and other essentials for your sleeping quarters. Shop the collections from Casper today.

Sources:

1. Nature and Science of Sleep. The Effect of Mattress Firmness on Sleep Architecture and PSG Characteristics. https://pmc.ncbi.nlm.nih.gov/articles/PMC12071755/
2. National Spine Health Foundation. Sleeping and the Spine. https://spinehealth.org/article/sleeping-and-the-spine/
3. Scientific Reports. The effect of long-term poor sleep quality on risk of back-related disability and the modifying role of physical activity. https://www.nature.com/articles/s41598-021-94845-7
4. Journal of Orthopaedics and Traumatology. What type of mattress should be chosen to avoid back pain and improve sleep quality? Review of the literature. https://pmc.ncbi.nlm.nih.gov/articles/PMC8655046/
5. Journal of Social & Health Sciences. Effects of mattress firmness and usage duration on low back pain: a hospital-based study from Lahore. https://www.logixsjournals.com/articles/53
6. Sleep Science and Practice. Effects of mattress support on sleeping position and low-back pain. https://sleep.biomedcentral.com/articles/10.1186/s41606-022-00073-x
7. The Lancet. Effect of firmness of mattress on chronic non-specific low-back pain: Randomised, double-blind, controlled, multicentre trial. https://www.researchgate.net/publication/8998133_Effect_of_firmness_of_mattress_on_chronic_non-specific_low-back_pain_Randomised_double-blind_controlled_multicentre_trial
8. BioMedical Engineering OnLine. Spine alignment in men during lateral sleep position: experimental study and modeling. https://biomedical-engineering-online.biomedcentral.com/articles/10.1186/1475-925X-10-103
9. Healthcare (Basel). Ergonomic Consideration in Pillow Height Determinants and Evaluation. https://pmc.ncbi.nlm.nih.gov/articles/PMC8544534/
10. Sleep Health. Effect of different mattress designs on promoting sleep quality, pain reduction, and spinal alignment in adults with or without back pain; systematic review of controlled trials. https://www.sciencedirect.com/science/article/abs/pii/S2352721815001400
11. Journal of Manipulative and Physiological Therapeutics. Effectiveness of a selected bedding system on quality of sleep, low back pain, shoulder pain, and spine stiffness. https://www.sciencedirect.com/science/article/abs/pii/S0161475402692243
12. Applied Sciences. Investigating the Impact of Long-Term Use on Mattress Firmness and Sleep Quality—Preliminary Results. https://www.mdpi.com/2076-3417/14/21/10016
13. National Pressure Ulcer Advisory Panel. Hand Check Method: Is it an Effective Method to Monitor for Bottoming Out? A National Pressure Ulcer Advisory Position Statement. https://cdn.ymaws.com/npuap.site-ym.com/resource/resmgr/position_statements/hand-check-position-statemen.pdf
14. Journal of Chiropractic Medicine. Effects of Mattress Material on Body Pressure Profiles in Different Sleeping Postures. https://www.sciencedirect.com/science/article/abs/pii/S1556370716300116
15. Applied Ergonomics. Biomechanical evaluation of four different mattresses. https://pubmed.ncbi.nlm.nih.gov/16169512/
16. Applied Ergonomics. Changes in sleep and wake in response to different sleeping surfaces: A pilot study. https://www.sciencedirect.com/science/article/abs/pii/S0003687011000858
17. Harvard Health Publishing. What type of mattress is best for people with low back pain?. https://www.health.harvard.edu/pain/what-type-of-mattress-is-best-for-people-with-low-back-pain
18. The Lancet. Medium firm mattresses reduced pain related disability more than firm mattresses in chronic, non-specific low back pain. https://ebm.bmj.com/content/9/4/119
19. Journal of Chiropractic Medicine. Subjective rating of perceived back pain, stiffness and sleep quality following introduction of medium-firm bedding systems. https://ww.sciencedirect.com/science/article/abs/pii/S0899346707601451
20. Applied Ergonomics. Effectw of prescribed sleep surfaces on back pain and sleep quality in patients diagnosed with low back and shoulder pain. https://pubmed.ncbi.nlm.nih.gov/20579971/