Is it better to have a medium or firm mattress? A personalized guide

September 23, 2025 •

4 min read

According to a systematic review published by the National Institutes of Health, a medium-firm mattress is often recommended to promote comfort and sleep quality, particularly for those with back pain. To answer the question, "Is it better to have a medium or firm mattress?" requires a deeper look into individual needs and preferences.

Quick Summary

The ideal mattress firmness is a highly personal decision, influenced primarily by your sleeping position, body weight, and existing health issues. While a medium-firm mattress offers a balance of cushioning and support that benefits many people, a truly firm mattress may be necessary for heavier individuals or stomach sleepers to ensure proper spinal alignment.

Key Points

Best for back pain: A medium-firm mattress is often more effective for back pain relief than an overly firm one, as it balances spinal support with comfortable contouring.
Consider your sleep position: Side sleepers generally need a medium mattress for cushioning, while stomach and back sleepers benefit from a firmer surface to maintain proper spinal alignment.
Body weight is a key factor: Heavier individuals typically need a firm mattress to prevent sinking, whereas lighter people often prefer a medium or softer surface for adequate pressure relief.
A generous trial is essential: To find the best fit, take advantage of mattress trial periods. Spend time lying down in your primary sleep position to test for comfort and pressure points.
Toppers can customize firmness: If your current mattress isn't quite right, a mattress topper can adjust the firmness without requiring a full replacement.
No one-size-fits-all solution: The best mattress is subjective. Your personal needs and preferences are more important than any universal rule.

Understanding the Mattress Firmness Scale

Before diving into the pros and cons of medium versus firm mattresses, it's important to understand the standard 1-10 firmness scale. On this scale, 1 is the softest and 10 is the firmest. A medium mattress typically falls in the 5-6 range, while a firm mattress is usually rated 7-8. The best firmness level for you is a subjective perception based on a combination of factors, not just a number on a label.

The Case for a Medium Mattress

A medium mattress offers a popular middle ground, providing a balanced feel that is neither too hard nor too soft. This versatility makes it an excellent choice for a wide range of sleepers.

Benefits of a medium mattress:

Superior pressure relief: For side sleepers, a medium mattress provides enough cushioning to cradle the hips and shoulders, distributing body weight evenly and preventing uncomfortable pressure points.
Excellent for combination sleepers: If you frequently change positions throughout the night, a medium mattress provides a good balance of comfort and support, adapting well to back, side, and stomach sleeping.
Reduces back pain: Research indicates that a medium-firm mattress is often most effective for reducing back pain, as it contours to the body while still offering robust spinal support.
Couples' compromise: For couples with different firmness preferences, a medium or medium-firm mattress can be the ideal compromise, satisfying both partners' needs.

Potential drawbacks of a medium mattress:

Less durable than firmer options due to more give.
May not provide enough support for heavier individuals, leading to excessive sinking.

The Advantages of a Firm Mattress

For those who need more robust support, a firm mattress can provide the stability necessary for a comfortable and healthy night's sleep. Many people believe a firm surface is the key to spinal health.

Benefits of a firm mattress:

Maintains spinal alignment: A firm mattress offers a flatter, more supportive surface that prevents the body from sinking too deeply. This is particularly beneficial for back and stomach sleepers, who need to keep their spine in a neutral position.
Better for heavier individuals: Sleepers over 230 pounds place more pressure on a mattress. A firm surface provides the necessary resistance to prevent sagging and ensure proper support.
Higher durability: Firm mattresses are generally more resilient and less prone to sagging over time, often boasting a longer lifespan.
Less motion transfer: A firmer sleep surface minimizes motion transfer, so you are less likely to be disturbed by a restless sleeping partner.

Potential drawbacks of a firm mattress:

Can create pressure points for side sleepers, leading to pain in the hips and shoulders.
Some people find the lack of contouring uncomfortable, leading to tossing and turning.

Matching Firmness to Your Sleep Style and Body Type

Choosing your ideal firmness is a personalized process. Your specific needs—your sleeping position, body weight, and any health concerns—should be your primary guide.

If you are a side sleeper:

You need a mattress that cushions your pressure points. A medium mattress is typically best, providing enough give to cradle your hips and shoulders while keeping your spine aligned.

If you are a back sleeper:

Your goal is a neutral spine. A medium-firm mattress is often the best fit, offering a perfect balance of comfort and support for the back's natural curve. You can check for a fit by lying on your back and sliding your hand under the small of your back. If it's too easy, it might be too firm; if you can't slide it in, it may be too soft.

If you are a stomach sleeper:

You need a firmer surface to prevent your midsection from sinking and arching your spine. A firm mattress provides the solid support necessary to keep your body level.

Considering your body weight:

Lighter individuals (under 130 lbs) may find a firm mattress too rigid. A medium or soft option will provide the necessary contouring and pressure relief.
Heavier individuals (over 230 lbs) need extra support to prevent excessive sinking and ensure proper spinal alignment. A firm or medium-firm mattress is typically the best choice.

Comparison: Medium vs. Firm Mattresses


Feature	Medium Mattress	Firm Mattress
Best For	Side and combination sleepers; back pain sufferers	Back and stomach sleepers; heavier individuals
Feel	Balanced, offers both cushioning and support; feels like sleeping "in" the mattress	Rigid, prioritizes support; feels like sleeping "on" the mattress
Pressure Relief	Excellent, contours to the body and relieves pressure points	Poor for side sleepers, can cause pressure points on hips and shoulders
Spinal Alignment	Good for most sleepers, promotes natural curvature	Excellent for stomach and back sleepers, prevents sinking
Durability	Good, though less durable than a firm mattress	Excellent, highly resistant to sagging over time
Motion Isolation	Good, though firmness is a larger factor for minimizing transfer	Very good, minimizes transfer from a partner's movement

When To Adjust Your Mattress

Even if you've chosen your mattress wisely, your needs can change. Weight fluctuations or new health conditions might make your current mattress feel too soft or too firm. Before investing in a new bed, consider a high-quality mattress topper. A softer topper can add plushness to a firm mattress, while a firmer topper can increase support.

Another option is to test your mattress and bed base. A new base or foundation can alter how the mattress feels, potentially increasing or decreasing its firmness.

Learn more about mattress firmness from the Sleep Foundation

The Final Verdict

Ultimately, there is no single answer to whether a medium or firm mattress is better. The right choice is the one that provides you with the most comfortable, supportive, and restorative sleep. Take the time to evaluate your unique sleep profile, and don't be afraid to try different options. With the right information, you can make an informed decision that will benefit your health for years to come.

Frequently Asked Questions

Yes, a mattress that is too firm can cause discomfort, especially for side sleepers. It may lead to pressure points on the hips and shoulders, disrupting sleep and potentially causing aches and pains.

If you notice that your hips or midsection are sinking too deeply into the mattress, causing your spine to curve unnaturally, it is likely too soft. This can lead to improper spinal alignment and back pain.

Combination sleepers, who change sleeping positions throughout the night, often find that a medium or medium-firm mattress provides the best balance of comfort and support for all their sleep needs.

Research suggests that medium-firm mattresses are generally best for people with back pain. This firmness level offers a balance of cushioning and support that promotes proper spinal alignment and relieves pressure.

Yes, body weight significantly impacts how a mattress feels. Lighter individuals (<130 lbs) may feel most comfortable on a softer surface, while heavier people (>230 lbs) need a firmer mattress for adequate support.

You can test a mattress in-store by lying on it in your typical sleeping positions for at least five to ten minutes. Pay attention to how your body feels and if any pressure points develop.

For couples with differing needs, a medium-firm mattress is a common compromise. Other solutions include a split-firmness mattress or placing two separate twin XL mattresses together to form a split king bed.

Generally, firm mattresses are more resistant to sagging and wear and tear, and therefore tend to last longer than softer or medium options.