Amerisleep AS4 Mattress Review

Amerisleep AS4 is an all-foam, three-layer mattress with some unique features. It has an advanced cover and a top layer of open cell foam to keep you cool, a transition layer that does an amazing job of supporting and cushioning, and a support base layer that won’t sag over time. It’s also one of the best mattresses for side sleepers and combination sleepers.

This highly rated mattress in a box is backed by a 100-night sleep trial, free returns, and a 20-year warranty. It is proudly made in the USA. Read on to learn more about the Amerisleep AS4.

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Is the Amerisleep AS4 the Right Mattress for You?

The Amerisleep AS4 is right for you if...

The Amerisleep AS4 isn’t right for you if...

You sleep on your side: If you are a side-sleeper, this bed is tailored for your needs. It is the right firmness and support to really address pain and help with good sleep.

You sleep on your stomach: The 4 out of 10 on the firmness scale is generally considered too soft for good spinal alignment for stomach sleepers.

You sleep hot: The AS4 is designed to breathe and to keep sleepers cool and comfortable at night and it does a great job in this category.

Want to sleep green: Although the AS4 has parts that are CertiPUR-Us certified against harmful chemicals and uses some plant-based sources, it is not a natural or organic mattress.

Want a sleep trial: You have a full 100 nights to sleep on the mattress and see if it is right for you. Most experts suggest a month or more to get used to a new bed.

Want to finance: Amerisleep does not offer financing at this point. Plan to pay with debit or credit card.

You want a warranty: The AS4 has a 20-year warranty which is twice what most manufacturers offer and twice the lifespan of the average online mattress.

You are a heavier sleeper: The AS4 is a big, thick, heavy mattress that in a queen size weighs 94 lbs. Since it comes as a bed-in-a-box you will need help to get it set up.

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The Amerisleep AS4 Mattress - An Overview

Amerisleep AS4 Mattress

  • Material: Layered memory foam
  • Firmness Level: Medium soft: 6/10
  • Customer Rating: 4.7/5
  • Trial Period: 100-night sleep trial
  • Warranty: 20-year limited warranty
  • Mattress Height: 12 inches
  • Sizes/Dimensions:
Twin 38” x 74”
Twin XL 38” x 80”
Full 54” x 75”
Queen 60” x 80”
King 76” x 80”
Split King 38” x 80” (x2)
Cal King 72” x 84”

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Amerisleep AS4 Mattress Features


Traditional memory foam mattresses have a density that is well known for trapping heat and sleeping hot. Your body temperature naturally lowers at night and sleeping hot can interrupt sleep.  Foam manufacturers have responded to this concern by changing the nature of memory foam to be more breathable or by adding gel to help keep it cooler. Amerisleep has constructed the top foam layer of their AS4 with a plant-based material and a more breathable structure that makes it very cool for sleeping.


How much your mattress bounces back is called its responsiveness. It is important because it determines how easily you can move around in the bed. Memory foam has a different kind of bounce from traditional innerspring mattresses, one that is slower and can be more difficult to maneuver.

Early kinds of memory foam were known for their heavy viscosity, the slow sticky way the mattress responded when you moved around on it. For many, this left them struggling to turn over during the night and some even described it as feeling like quicksand — an uncomfortable sinking feeling.   Mattress companies have continued to refine this particular quality in their memory foam mattresses and the Amerisleep AS4 is considered superior for responsiveness. The company advertises that their foam “bounces back fast, so you never feel stuck.” This quality also makes Amerisleep a top provider of the best mattresses for heavy people.

Motion Isolation

Memory foam has an outstanding quality when it comes to movement.  Unlike other mattresses where motion on one side of the bed can transfer throughout, memory foam isolates motion and keeps it localized. The quality of good motion isolation lets more than one -person sleep in a bed undisturbed by the movement of others. You can roll over, sit on the edge, or have the dog jump on and or off the bed, and it will not be felt on the other side.

Pressure Relief

The same property that can make memory foam hard to move around on also gives it the ability to more fully contour and mold around your body, giving you such great support and pressure relief. Mattresses like the Amerisleep AS4 are especially loved by side sleepers and combination sleepers because nothing supports shoulders and hips like good memory foam. It is also great for supporting the back and reducing lower back pain.

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Amerisleep AS4 Mattress Materials

Inside layers of AS4 Mattress

What’s Inside?

  1. High-performance cooling cover: This cover has a technology that takes your body heat and pulls it away from you, keeping you resting at a cool temperature.
  2. Bio-Pur foam: The top layer of foam in the Amerisleep AS4, sometimes called the comfort layer, is what you sleep on most directly. This layer has a Bio-Pur formula with an open cell structure for breathability. This keeps your body heat in circulation rather than letting it build up, and accounts for why the mattress sleeps cool. It also has outstanding bounce back or responsiveness, letting you move around with ease.
  3. Affinity layer: This thinner transition layer works to give support as needed and keep your spine aligned. It gives more support to areas like your head and back, and more cushion to areas like shoulders and hips, creating a comfortable balance with medium firmness.
  4. Bio-Core foam support layer: Made from eco-friendly plant-based materials instead of synthetics, this foam support layer is extra-durable. The support foam won’t sag or become uneven, and Amerisleep is so confident of that, they back it with a 20-year warranty—more than double the average life of a mattress.

Compatible Foundations

Amerisleep AS4 doesn’t come with a base, but it can be used with almost any type of frame or foundation.  A base off the floor helps keep your mattress away from drafts, keeps it cleaner, and minimizes wear, which extends the life of the mattress. The Amerisleep AS4 is compatible with:

  • Platform beds: Platform beds are typically low-profile bases that, like the bed, have clean lines and don’t take up much space. They work well for the AS4.
  • Box springs: Amerisleep AS4 can be used with a box spring if you like that look or your frame requires one.
  • Adjustable beds: Amerisleep AS4 is made of memory foam — the ultimate in bendable mattress materials. It is designed to move with an adjustable bed and is a great fit for this type of frame.
  • Traditional frames: Already have a frame you love? No worries, you can use it with the AS4. It may need a bunkie board, box spring, or other reinforcement if it is not built into the frame.
  • Daybeds: These are usually a form of platform bed and easily compatible with the Amerisleep AS4 mattress.

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Best Sleeping Positions for the Amerisleep AS4 Mattress

Amerisleep AS4 is a mattress that can accommodate all sleep positions, but the level of responsiveness of this mattress makes it great for combination sleepers who change throughout the night.

For Side Sleepers

Amerisleep AS4 was not designed exclusively for side sleepers, but many side sleepers believe it was. It really is a side sleepers’ dream with all the right support and responsiveness in a medium soft mattress. It contours from top to bottom supporting head, neck, shoulders, waist, hips, legs, and feet.

Read more about the best mattress for side sleepers.

For Back Sleepers

Amerisleep AS4 can work for some back sleepers with its combination of firmer base support and softer top layer. Medium to medium-firm mattresses are suggested if you sleep on your back, but a medium soft mattress can work with a lower loft pillow.

For Stomach Sleepers

To keep your spine aligned when sleeping on your stomach, it is important not to sink very deeply into the mattress. Thus, a firmer mattress is best for stomach sleepers. The Amerisleep AS4 would not be recommended for stomach sleepers.

More About Amerisleep

Amerisleep is a US company that supports a locally made product. They have developed a plant-based foam that is luxurious, supportive, and responsive. They make a line of mattresses with different firmness levels. Here is a little bit more about them.

Eco-Friendly Materials

Although the Amerisleep AS4 is not an organic mattress, Amerisleep is controlling for toxic chemicals and off-gassing and sourcing more high-quality, plant-based, and eco-friendly materials. Amerisleep has Bio-Pur, a material that is processed with zero-emissions and the eco-friendliest material of its kind.

Made in the USA

Amerisleep is made in the USA, which has a number of advantages. The US often has stricter standards for processing, for treatment of employees, and for labeling of materials. Made in the USA products support local jobs and the local economy where the mattresses are made, in this case in Indiana.

Free Shipping and Free Returns

Amerisleep has free shipping and a great return policy. There is no cost to you either way. That means that if you return the mattress within the 100-night trial, it will cost you nothing. They cover the shipping, there are no restocking fees, and no hidden fees of any kind. Amerisleep prides itself on transparency and you won’t incur any costs if you return your mattress.

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Other Mattresses Sold by Amerisleep

Amerisleep offers a full line of different mattresses for every type of sleeper in all levels of firmness. These Amerisleep models are coded AS1 through AS5 and get more expensive and have more loft as the number increases. Check out a little more of these Amerisleep mattress reviews below.

Amerisleep AS1

AS1 Mattress

The AS1 is the firmest of the Amerisleep mattress line. It is a great mattress if you want extra support and sleep on your back or stomach. The mattress is considered firm, yet still quite comfortable and has cooling properties. A slimmer mattress, it is 10 inches in height.

Great for:

  • Back and stomach sleepers
  • Hot sleepers
  • Edge support

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Amerisleep AS2

AS2 Mattress

The AS2 is the next in line with a firmer bed and a slightly higher price-point. It is considered a medium firm bed and is great for back and stomach sleepers, especially because of its great motion transfer performance. It sleeps cool and has a slightly higher profile at 12-inches.

Great for:

  • Back pain relief
  • Back and stomach sleepers
  • Targeted pressure relief

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Amerisleep AS3

AS3 Mattress

The AS3 mattress is the middle in the Amerisleep lineup and considered a solid medium on the firmness scale. It is their most popular memory foam bed and great for all sleep positions. It has a 12-inch profile.

Great for:

  • Couples
  • All sleep positions
  • Targeted pressure relief

Find out more in our Amerisleep AS3 mattress review.

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Amerisleep AS5

AS5 Mattress

The top of the line for Amerisleep, this 14-inch mattress is their softest mattress. It is extra plush and extra supportive. It is very breathable and helps relieve pain.

Great for:

  • Side sleepers
  • Better circulation
  • Hot sleepers

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Other Sleep Accessories Sold by Amerisleep

Lift by Amerisleep

Lift mattress topper

This mattress topper comes in a soft and firm option to help make your current mattress be better suited for your sleep needs.
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Amerisleep Foundation


This platform base with legs is designed to support the Amerisleep line of mattresses including the AS4. It is used in place of a box spring and has a low 8.5-inch profile. Easy assembly.
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Amerisleep Adjustable Bed

Adjustable bed

To customize your sleep even further, add an adjustable base. It has almost unlimited positions for great support and is designed to fit Amerisleep mattresses. Comes with remote, full-body massage, under bed lighting, and USB ports.

30% off Adjustable Bed and Adjustable Bed+ bundles

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Amerisleep Comfort Classic Pillow

Comfort classic pillow

This foam pillow has the Bio-Pur open cell foam that wicks heat and keeps you cool. It is CertiPUR-Us certified against harmful chemicals and comes with a 100-night sleep trial and free shipping and returns.
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Amerisleep Percale Cotton Bed Sheet Set

Percale cotton bed sheet set

Amerisleep offers 300 thread count 100% cotton sheet sets that are breathable and cool. They come in four options: light or dark grey, with or without stripes.
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Amerisleep Tencel Sheets

Tencel sheets

For a more luxurious feel, Amerisleep offers a Tencel sheet set made from this sustainable material. They are extra soft and cool for a more relaxed and deeper sleep experience.
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Amerisleep Percale Duvet Cover Set

Percale duvet cover set

This cover is made from 300 thread count 100% long-staple cotton that is cool and breathable. It comes in four options: light or dark grey, with or without stripes.
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Amerisleep Waterproof Mattress Protector

Waterproof mattress protector

This 100% waterproof mattress cover is poly laminated and the gold standard of mattress covers. It will extend the life of your mattress and protect against any kind of spills.
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Amerisleep AS4 Mattress FAQs

  1. Can I finance my Amerisleep AS4 mattress?

    You can certainly use a credit card or find personal financing, but currently Amerisleep does not offer financing.

  2. Is there a store where I can test out the Amerisleep AS4 mattress?

    Yes, there are a growing number of stores, but currently they are only located in four states: Arizona, Colorado, Oregon, and Texas. They have stores in multiple cities in many of these states, and you are welcome to come and see how their mattresses feel.

  3. How long will it take for my Amerisleep AS4 mattress to be delivered?

    The range for delivery is from 4 to 10 days. This includes the 3 to 5 days it takes to ship from the factory in Indiana, and the 1 to 5 days in transit. Where you live in the county makes a difference, as well as if it’s a high-volume time of year like during sales.

  4. How does the sleep trial work?

    Sleep trials are a great addition to the mattress buying experience because it gives you time to fully try your new mattress. It takes about 30 days to adjust to a new mattress and to know if it is right for you. Amerisleep offers a 100-night trial so you can sleep on your mattress for over three months and if you don’t like it, you can return it and they will pay for shipping.


Amerisleep is an innovative online and retail mattress company with a complete line of mattresses from firm to super soft. They pride themselves on meeting the needs of every sleeper and every body type. They further use eco-friendly materials and processes. Their mattresses are made in the USA, have a 100-night sleep trial, free returns if it isn’t the right fit, and are warrantied for 20 years (which is twice the industry average).

The Amerisleep AS4 profiled in this review is best suited for side sleepers with a medium soft feel. It offers great pressure relief, promotes better blood circulation, and reduces pain. It is breathable and has cooling properties to keep you comfortable all night.

  • Side sleepers and combination sleepers will appreciate the perfect mixture of soft plush comfort and medium firm support.

  • Couples will enjoy the motion isolation for undisturbed sleep.

  • Everyone will benefit from less pain and better circulation for a feel-good morning.

If you think the Amerisleep AS4 is the right mattress for you, you can purchase online. As an add on, consider one of the Amerisleep accessories like a great pair of eco-friendly Tencel sheets. They have easy ordering and great customer service support. There are no worries if you don’t like your mattress, just return it within the 100-day trial period. You have nothing to lose and a great night’s sleep to gain. Ready to give it a try?

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About the Author Sheryl Grassie

Sheryl is a professional writer and researcher with a long-time interest in sleep and how sleep affects health and weight. She writes on topics related to nutrition, diet and lifestyle, and of course good sleep.