A Mattress Thickness Guide: Find What You Need

A Mattress Thickness Guide: Find What You Need

How thick should a mattress be? Standard mattresses are between six and nine inches. Any mattress thicker than that is usually considered a luxury item. 

They don’t make mattresses like they used to – and that’s a good thing! Old-fashioned, poorly constructed mattresses filled with coils that poke through the encasings are (hopefully) a thing of the past. Today, mattresses are manufactured thoughtfully, prioritizing the customers’ comfort. 

For many people, a thick mattress represents high quality and comfort. The thicker, the better. Of course, this is not the case for everyone. Mattress thickness is a crucial factor that determines comfort.

To determine how thick of a mattress you need, you should consider at least three things: body distribution, mattress firmness, and pain issues. The position you sleep in is also a determinant.

This guide will discuss what thick mattresses are made of, the parameters for choosing mattress thickness, and why SONU’s mattress is the best option available.

What Are Thick Mattresses Made Of?

Before getting into what thick mattresses are made of, take a look at this handy mattress thickness chart:

Thickness Level


Very thick

15 - 20 inches


13 - 14 inches


10 - 12 inches


5 - 8 inches

Mattress topper

1 - 4 inches

The difference between each level is significant, which is why choosing the correct amount of thickness needed is important. Here’s what the thickest mattresses are typically made of.

Thick mattresses 13 inches or more are typically made of several transition and comfort layers. These layers are sometimes made of memory foam and latex. Some mattresses are hybrids that use a support layer made of intricate coil systems encased in another material.

SONU Sleep’s mattresses contain layers of memory foam that are topped off with Serene foam, a new material on the market. These mattresses feel unlike any other, delivering a cool, lavish sleep experience. 

SONU’s original, negative space mattresses are 14 inches thick. Unlike average mattresses, SONU’s come with a patented Comfort Channel and a set of support pillows. If you’re ready to sleep like royalty, try the SONU Sleep System.

What Are the Pros and Cons of Thick Mattresses?

Thick mattresses do not suit every sleeper. They will either improve your sleep or leave you unsatisfied. 

No one wants to be unsatisfied with their mattress choice. Below are the pros and cons of thick mattresses.


  • Provide the best support for heavy sleepers
  • Made with lush sleep surfaces
  • Provide the most support for co-sleepers
  • Last a long time


  • Cost more than a standard mattress
  • Weigh more than smaller mattresses and are hard to move
  • Not easy to get off of by people with limited mobility

In general, the thicker a mattress is, the longer it will last. So if you want a mattress you don’t need to replace for quite a while, a thick mattress is a good choice.

The thickness of your mattress will affect your sleep quality. Whether it improves or degrades it depends on your situation. Either way, once your sleep quality changes, your health will change like a domino effect. 

Choosing the right amount of mattress thickness can change your life for the better.

What Size Mattress Do You Need?

SONU carries Twin XL, Queen, King, Cali King, and Split King mattresses. Just how much mattress a person needs varies by height and weight. Smaller people may feel comfortable sleeping on a Twin XL or Queen bed, while taller, heavier people need a King bed or above to accommodate them.

The dimensions of each mattress type are as follows:

Mattress Size


Twin XL

38” W x 80” L x 14” D


60” W x 80” L x 14” D


76” W x 80” L x 14” D

Cali King

72” W x 84” L x 14” D

Split King

76” W x 80” L x 14” D

Weight and body type can help determine the dimensions that someone’s mattress needs to be. For example:

  • 6 to 9 inch mattresses are usually good enough for light-weight sleepers who weigh 130 pounds or less.
  • 10 to 12 inch mattresses are recommended for people who weigh between 130 to 230 pounds.
  • 12 to 14 inch mattresses are suitable for sleepers who weigh 230 pounds or more.

How Firm Do You Want Your Mattress?

The mattress firmness scale includes the following levels: extra-soft, soft, medium, medium-firm, firm, and extra firm. The scale rates mattresses from levels 1 to 10. The firmer the mattress, the less “give” it has.

Here are brief descriptions of each firmness level.

Extra Soft

This is the softest mattress level you can buy. It rates between levels one and two. The plushest mattress available, the extra soft mattress allows the body to sink into it. The comfort layer of extra soft mattresses tends to be very thick so that it can conform to the body and provide pressure relief.


Soft mattresses rate between the levels of three and four. They also contain thick comfort layers to provide pressure relief. Many back sleepers prefer soft mattresses because they do not overextend the lower back. 

Soft mattresses of about 12 inches are ideal for lightweight sleepers.


Rated at levels five and six, medium mattresses are popular for most sleeping positions. They may have plush cushioning but have support cores that help improve spine alignment. They’re ideal for the average sleeper or side sleepers who prefer plush sleeping surfaces. 


Medium-firm mattresses rate between six and seven. The average sleeper would be comfortable on a medium-firm mattress between 10 and 12 inches thick. Again, side sleepers tend to gravitate toward medium-firm mattresses because they have a soft sleeping surface but a strong support core.

If you’re looking for a plush, medium-firm mattress, try SONU’s Sleep System. All of SONU’s mattresses are 14 inches thick and consist of 26 layers of the most luxurious memory foam and Serene foam you’ll ever sleep on.


Firm mattresses rate between seven and eight. They’re ideal for back sleepers and sleepers who are 230 pounds or more, especially if they are 12 to 14 inches thick. The thickness and firmness of the firm mattress provide extra support and prevent sagging.

Extra Firm

Extra firm mattresses rate between nine and 10. They are recommended for back sleepers who prefer very rigid mattresses. For many people, this mattress level is too hard. However, like firm mattresses, extra firm mattresses are less likely to sag.

Do You Have Any Pain Issues?

If you are suffering from a pain issue, the severity of your issues and your mobility should be factored into your mattress depth decision. 

If you experience chronic pain, a mattress that is too thick might not have the right amount of pressure relief you need.

A thicker mattress will make beds taller, especially if you use a box spring. If the height of the bed is already high, a thinner mattress might be in order. 

Height is a factor if you have mobility issues – if it would be too difficult to get out of a tall bed, consider a mattress with fewer inches. If you have arthritis, joint pain, or back pain, your bed should be no higher than 25 inches to allow better mobility.

If back pain is a problem, mattresses between 10 and 12 inches are the best choice because they do not sink in as much while providing support for the spine.

What Position Do You Sleep In?

Your sleeping position can also help identify how thick your mattress needs to be. This is because certain positions require more cushioning or support than others. The thickness should be considered when shopping for position-specific mattresses.

Here are the recommended thickness measurements according to popular sleeping positions:

  • Mattresses that are 10 inches or more are ideal for stomach sleepers. These sleepers also require less support.
  • 6 to 9 inch mattresses are great for back sleepers, who need support that will keep their spines in alignment. The mattresses should also be flexible enough to fit the lower back curve.
  • 8 to 10 inch mattresses are alright for side sleepers. Mattresses of this depth provide adequate support for the shoulders and hips.

SONU’s mattresses were made with side sleepers in mind. Each 14 inch mattress has a unique, 10 inch deep Comfort Channel for sleepers to let their shoulders and arms sink into while they sleep. This takes the pressure off those parts of the body, preventing soreness common when sleeping in the side position.


Mattress thickness is important. To find the right mattress height, body composition, pain, mattress firmness requirements, you should consider your sleeping position. 

The thicker the mattress, the more luxurious it is considered to be. When it comes to mattress depth and luxury, SONU does not disappoint. 

The SONU Sleep System is made up of several layers of sumptuous foam and it is topped off with a layer of the latest cooling material on the market – serene foam. Side sleepers, people with shoulder, arm, or hip pain, and people who need heavy support will all enjoy the SONU Sleep experience.

Leave thin, non-supportive mattresses behind and purchase a SONU mattress today. You won’t regret it.


Can a mattress be too thick?

This depends on your preferences. However, if you have mobility issues, getting off of a thick mattress might be a bit of a challenge.

Are SONU’s mattresses really 14 inches in depth?

Yes! All of SONU’s mattresses, including the Twin XL, include 26 layers of memory foam topped off with Serene foam. 

How thick should my mattress be if I sleep with a partner?

If you sleep with a partner, you will need something that is thick and strong enough to support both of you. A medium-firm, thick mattress of 13 inches or more would be ideal.

Thick mattresses are expensive. How can I save money and increase mattress thickness?

Some people increase the thickness of their mattresses by adding mattress toppers, which typically range between 1 and 4 inches. 

If you would rather upgrade your mattress, SONU offers financing that requires $0 down, and you would only have to pay $84/month for up to three years with 0% APR financing



Mattress Sizes: Dimensions & Chart | Sleep.org

How To Choose Your Mattress Thickness | Santa Monica College

Differences in the body pressure-related sensory changes between the floor and mattress in a static supine position for physiotherapy research: a randomized controlled pilot trial | NIH

Question About Mattress Thickness: How Thick Should My Mattress Be? | Home DIT

Designed To Work Together
The SONU Sleep System

It is finally time to immerse into comfort, and sleep like never before.

The SONU Sheets

Soft, cooling and sustainable, with the Comfort Channel built in to fit your SONU.

The SONU Top Pillow Deluxe

The perfect amount of support and malleability to complement your SONU.

Trusted Reviews From Side Sleepers Nationwide
Shoppers and their reviews verified by Fera.ai
Thank YOU! Best mattress out there.
After being a gymnast for 15 years, I haven't felt this much relief from the pain in my shoulders and my hips while sleeping!! Thank you!
Steph C.
Highly recommended!
Creates the perfect space for your arm if you're a side sleeper. Changed the way I sleep forever.
Justin S.
So I actually own one of these. It's AMAZING. Yes it will take you a few weeks to get "used" to it... But that said, you will be AMAZED at how great your shoulders feel in the morning. Just unreal. Like sleep a full 8 hours without waking up type of sleep.
Jason R.
Buffalo, NY
I have very bad neck and back issues and this mattress is a dream! If you are a side sleeper you will love it and even if you like to sleep on you back you will love it! Very comfortable and totally worth the money!
Grace L.
i have suffered from shoulder pain while sleeping for several years, i had just about given up... then i saw this bed and decided one last try. i can't begin to explain what it feels like to sleep through an entire night... for the first time in 20 years the first weekend i had it. I'm so impressed with this bed... because what they are making is making a difference in people's lives.
Crystal G.
Lives up to the hype
This comfort channel they made is next level. I never imagined that I would be able to put my arm in the mattress. Takes all the pressure off my shoulder, which I so so need. YES
Kim J.
Highly recommended!
I’m a side sleeper and I used to wake up with a dead feeling arm from lying on it all night. Finally a mattress with a pocket for my arm. I tried all the pillows and even very expensive mattresses in the past, but nothing cured my circulation problems until I got the sonu sleep mattress. I love it!
Nic D.
Chicago, IL
...Sonu mattresses are in a league all by themselves. This is the most comfortable bed I have ever slept on. I have no more shoulder pain and numbness. I can now sleep through the night and not wake up in pain. If anyone is even thinking about getting a Sonu sleep system don’t think anymore. Pull that trigger. I 100% gaurentee you will not be disappointed.
Christopher B.
Made In The U.S.A.
Image of the red, white and blue U.S. flag
The SONU Sleep System was designed and developed in California, and is manufactured only in the United States - made with the highest quality materials and attention to detail for side sleepers everywhere.
* SONU Bedding and several SONU Supports are imported products. All other SONU products are made in the United States.

Finally let your arms rest where they're meant to...