Our In-Depth Amerisleep AS4 Mattress Review for 2023

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Amerisleep was founded in 2010 with a focus on making high-quality, American-made, and eco-friendly mattresses at an affordable price. Today, we’re checking out the Amerisleep AS4, the company’s second-softest model. This 12-inch all-foam bed is non-toxic and made with Bio-Pur®, a memory foam that’s partially made using renewable plant-based oils – perfect for those who care about the future of the planet.

While this bed is designed with side sleepers in mind, it also suits some back sleepers, and if you hit the gym a lot, listen up – it features technology that could possibly speed up muscle recovery. Intrigued? You’d better read on.

Amerisleep AS4 Mattress
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An all-foam, pressure-relieving bed made with side sleepers and eco-conscious shoppers in mind.
Click the button below to get the Amerisleep AS4 Mattress.

Who We Recommend The Amerisleep AS4 For:

  • Side sleepers – This mattress has plush memory foam that offers exceptional pressure relief at the hips and shoulders.

  • Active people – If you exercise a lot and frequently have sore muscles, then this bed could be the one for you. The cover features minerals that are reportedly able to convert body heat into infrared energy, which helps increase blood circulation so muscles can recover faster.

  • Eco-conscious shoppers – Bio-Pur® memory foam is partly-made with renewable plant-based oils, and these beds are manufactured using Variable Pressure Foaming (VPF), which is the most eco-friendly process available. Waste from this process is also 100 percent recycled internally.

Who We Don’t Recommend The Amerisleep AS4 For:

  • Stomach sleepers – This mattress is on the softer side, so we don’t recommend it for most stomach sleepers, who will require something firmer to keep those hips lifted and the spine in alignment. Exceptionally lightweight stomach sleepers may find it supportive enough, but we think it’s a no-go for most front sleepers.

  • Most heavyweight people – This slightly soft mattress could provide a good balance of support and pressure relief for heavy side sleepers between 230 and 300 pounds, but heavier sleepers above that weight range – as well as back and stomach sleepers – will likely find themselves bottoming out.

First Impressions: Firmness & Feel

Firmness Scale: 6/10

Please remember that firmness is a subjective characteristic and your shape will dictate how you experience a bed. A heavier person whose weight can more easily push through softer comfort and support layers may experience a bed as softer than a lightweight person. The way you are shaped could also play a role here. Consider your weight, shape, and size when evaluating firmness scores.

Mattress Firmness Level 6

We placed the Amerisleep AS4 at a 6 out of 10 on our mattress firmness scale, which ranges from 1 to 10, with 1 being the softest. The industry standard for medium-firm is 6.5 out of 10, making this bed slightly softer than average.

This could make it ideal for the majority of side sleepers, who often prefer a softer mattress to avoid pressure buildup at potentially sensitive areas like the hips and shoulders. However, a mattress that’s perfect for side sleeping can mean it's not good for stomach sleeping, and we found this to be the case with the Amerisleep AS4.

How Does It Feel?

Place your hand on the Amerisleep AS4, and you’ll experience its cool-to-the-touch cover, which should help regulate your body temperature while you sleep. If you push your hand further down into the comfort layer, you’ll find a balanced foam feel that’s simultaneously responsive and pressure-relieving. At 4 inches, the comfort layer is the second thickest of all Amerisleep mattresses, offering a rather plush and cozy feel.

What We Like About the Amerisleep AS4

  • Exceptional pressure relief – The 4-inch layer of memory foam and five-zoned transition foam work together to provide targeted support and pressure relief, which offers a soothing, gentle cradle for the joints.

  • Durability – This bed is constructed with durable materials, and Amerisleep is so confident of its longevity that they offer a longer-than-average 20-year warranty.

  • Responsive memory foam – Traditional memory foam can leave you feeling ‘stuck’ in the mattress, but Amerisleep’s Bio-Pur® memory foam has a good amount of bounce with a quick response time. This makes it much easier to move around on the bed.

Our Amerisleep AS4 Complaints

  • Not firm enough for many – While this bed could be a great choice for most side sleepers, we think stomach sleepers and many back sleepers will find it’s not firm enough.

  • Edge support could be better – Softer beds can often lack edge support, and while the edge support offered by the Amerisleep AS4 is okay, it might not be adequate for those who like to sleep close to the perimeter, as they may experience sagging at the edges.

Testing the Amerisleep AS4 Mattress: How it Performed

We assess each mattress for important factors like support, pressure relief, motion isolation, edge support, cooling, and responsiveness. We also look at how comfortable the bed is for side, back, and stomach sleeping. These tests help us narrow down who we think could be a good match for the product.

Sleeping Positions for Different Body Types

Twin, Twin XL, and Full sizes of the AS4 mattress can support up to 400 pounds, while Queen size and above can handle 400 pounds on each side, at 800 pounds total. However, we don’t recommend this bed for most heavyweight folk weighing over 230 pounds, as it’s likely too soft to provide the required support.

Weight Side Sleepers
Side Sleeping Icon
Back Sleepers
Back Sleeping Icon
Stomach Sleepers
Stomach Sleeping Icon
Lightweight Sleepers (-130 lbs)★★★★★★★☆☆
Average-Weight Sleepers (130-230 lbs)★★★★★☆☆☆☆
Heavyweight Sleepers (+230 lbs)★★☆☆☆☆☆☆☆

Side Sleepers

  • Lightweight Sleepers – Lightweight side sleepers should experience amazing pressure relief coupled with great support, which is the perfect recipe for a good night’s sleep.
  • Average Weight Sleepers – We think this mattress is a great match for average-weight side sleepers, who should sink deep enough into the comfort layer to experience fantastic pressure relief while also feeling supported.
  • Heavyweight Sleepers – Most heavyweight side sleepers should experience a lovely balance of pressure relief and support, with the five-zoned foam cradling them in all the right spots. However, those over 300 pounds will likely need a more supportive bed.

Back Sleepers

  • Lightweight Sleepers – Lightweight sleepers tend to experience mattresses as firmer than advertised, so we think lighter back sleepers will find great spinal support from this mattress, as well as fantastic pressure relief.
  • Average Weight Sleepers – Back sleepers weighing between 130 – 200 pounds should feel well-supported while experiencing great pressure relief. However, those over 200 pounds will likely find there’s not enough support in the lumbar area, which could lead to pain over time.
  • Heavyweight Sleepers – The Amerisleep AS4 isn’t a good choice for heavier back sleepers, who likely won’t receive the support they need in this position.

Stomach Sleepers

  • Lightweight Sleepers – Exceptionally lightweight stomach sleepers may find adequate support from this mattress, but we think most lighter folk will still find it too soft to provide the required spinal support.
  • Average Weight Sleepers – We wouldn’t recommend this mattress for average-weight stomach sleepers, who will likely find it too soft. This could cause you to sink too deeply into the bed, taking the spine out of alignment.
  • Heavyweight Sleepers – This mattress is far too soft for heavyweight stomach sleepers, who will need something more supportive to keep their hips raised and prevent back pain.

Pressure Relief & Pain

The Bio-Pur® memory foam and five-zoned HIVE® transition foam in this mattress work in harmony to contour the body and help relieve painful pressure points. We found the foams lived up to their pressure-relieving promises when sleeping on our side; side sleepers under 200 pounds and light to average-weight back sleepers will best experience this pressure relief while also feeling adequately supported by the foam.

Back Pain – Back sleepers under 200 pounds should find back pain soothed, but those weighing over that will likely find any pain exacerbated, as their hips will sag out of alignment on this slightly soft mattress.
Hip Pain – Side sleepers under 300 pounds should experience fantastic pressure relief at the hips, with the five-zoned foam helping to soothe any aches and pains. However, most stomach sleepers and heavier back sleepers will likely experience a buildup of pressure, as they’ll find themselves sinking too deeply.
Shoulder Pain – Again, side sleepers under 300 pounds are in luck with this mattress – those with sensitive shoulders should find a good amount of pain relief, thanks to the contouring provided by the foam layers.


This bed provides great support for most side sleepers and light to average-weight back sleepers, with zoned targeted support provided by the HIVE® layer.

Due to its soft foams, we found edge support to be slightly lacking, as expected. It’s not the worst we’ve experienced, but it’s not great either. Therefore, if you’re someone with limited mobility who needs a solid perimeter to help you get in and out of bed, this mattress may not be a good choice for you. Couples who like to use the whole surface area of the bed may also find themselves feeling like they’re about to roll out.

Motion Transfer

Despite its responsive foam, the Amerisleep AS4 has great motion isolation, which is good news for those who share their bed with restless partners or pets. The top layer of Bio-Pur® memory foam helps to absorb motion, isolating movement to one side of the mattress.

Temperature Regulation / Cooling

Hot sleepers or those who live in warm climates are best off shopping for a cooling mattress, to help avoid any uncomfortable night sweats.

The Amerisleep AS4 has two cooling features. First, there’s the Refresh Cover, which contains fibers that draw heat away from the skin. Second, there’s the Bio-Pur® memory foam, with an open-cell design that allows air to flow through and escape, preventing heat build-up. However, as it’s an all-foam mattress, it may still sleep hotter than a hybrid.

Performance for Couples

Couples sharing a bed usually have different requirements than solo sleepers when shopping for a new mattress. First, you have to make sure the firmness level suits you both – this mattress could be ideal for light to average-weight couples who sleep on their side or backs. The mattress has great motion isolation, which is helpful if one of you tosses and turns a lot, and it’s fairly responsive, making it a good choice for sex.

Its cooling technology could be adequate for those who overheat when sharing a bed, but we think it might sleep too hot for some. Edge support was okay but not the best, which is something to consider if you like to spread out across the bed.

Preference-based Features

Good Bounce

Considering this is an all-foam mattress, we think Amerisleep has done a good job with its responsive memory foam. The bed is fairly responsive, with a good amount of bounce.

Eco-Conscious Materials

Lots of foam beds feature materials made with non-renewable resources, but the Bio-Pur® memory foam used in this bed is partially made with renewable plant-based oils. The foam does still contain some crude oils, but it’s a step in the right direction.

Made in the USA

Every Amerisleep mattress is made in the USA.

Adjustable Base Compatible

You can place your Amerisleep AS4 on an adjustable base without damaging it, and Amerisleep sells its own adjustable bases (in Twin XL size upwards), starting at 1,800 dollars.

Construction: What’s Inside the Amerisleep AS4?

The Amerisleep AS4 is an all-foam, eco-friendly, and non-toxic bed with a 12-inch profile. It starts with a cool-to-the-touch Refresh Cover that’s ultra-breathable and made from a fiber that draws heat away from the body. The company claims that on average, the sleeping surface will stay 7 degrees cooler over an eight-hour sleep.

The cover is made with Celliant® fabric, which is constructed with minerals that are reportedly able to convert body heat into infrared energy. This increases blood circulation, helping to speed up muscle recovery.

  • The comfort layer is made from 4 inches of partially plant-based Bio-Pur® foam, a more eco-friendly memory foam. This layer has a large open-cell design, which allows more air to escape than traditional foam, helping to keep you cool. This foam is made to contour the body, offering pressure relief where you need it most. It’s also more responsive than traditional foam, with a fast bounceback that should allow you to change sleeping positions with more ease.
  • The transition layer features 1 inch of HIVE foam that’s zoned to offer targeted support in five areas. It’s firmer around the head, back, and legs for extra support, and it’s softer at the shoulders and hips for added pressure relief.
  • The base layer is made from 7 inches of high-density Bio-Core® foam, offering support and durability for the rest of the mattress.
Amerisleep AS4 Mattress Construction

Unboxing & Off-Gassing

Your mattress will be delivered to your doorstep compressed in a box. Take it to your bedroom, remove the mattress, place it on the bed, and then use the supplied cutting tool to remove the plastic packaging. The mattress will slowly begin to expand, and while it may take up to 24 hours to reach full size, you can sleep on it straight away.

As with most bed-in-a-box foam models, we experienced some off-gassing. This is an unpleasant yet harmless odor that’s caused by chemical by-products escaping from the foam after being compressed. Leave the bed in a ventilated room for a few days and the smell should be gone.


  • Eco-Friendly Certifications – The foams in this bed are CertiPUR-US® certified. CertiPUR-US® is a third-party program that ensures the foams meet rigorous health and safety standards. This means they don’t contain harmful substances like ozone depleters, PBDEs, heavy metals, formaldehyde, and phthalates. They should also have low volatile organic compound (VOC) emissions.

Coupons, Trials, Warranties, and Shipping

  • Shipping – There’s free bed-in-a-box FedEx shipping within the continental United States. For orders outside of this area, customers can arrange their own freight forwarding.
  • White Glove Delivery – White glove delivery is not offered with this bed.
  • Trial – You’ll have 100 nights to test out your Amerisleep AS4 to see if it’s the bed of your dreams.
  • Warranty – There’s a 20-year warranty on the Amerisleep AS4. For the first 10 years, you’ll receive a replacement if you experience any defects, including sagging greater than 1 inch. For the second half of the warranty, you’ll be offered a prorated replacement.
  • Return Policy – Returns are free as long as you’ve slept on your bed for at least 30 nights (to allow you to get used to it), and you’ll receive a full refund. If you want to return your bed within the first 30 nights, you’ll incur a 90-dollar early processing fee.

Sizes & Prices

SizeDimensions (inches)Price (w/o discount)
Twin38” x 74” x 12”$1,499
Twin XL38” x 80” x 12”$1,549
Full54” x 75” x 12”$1,699
Queen60” x 80” x 12”$1,749
King76” x 80” x 12”$2,049
Cali King72” x 84” x 12”$2,049
Split King76” x 80” x 12”$2,648
Amerisleep AS4 Mattress
Get the Amerisleep AS4 Mattress
An all-foam, pressure-relieving bed made with side sleepers and eco-conscious shoppers in mind.
Click the button below to get the Amerisleep AS4 Mattress.

Frequently Asked Questions

What is the AS3 vs. the AS4?

The Amerisleep AS4 is slightly softer than the AS3 model, with a thicker comfort layer that is more suitable for side sleepers. The AS3 is the company’s best-selling mattress and is also available as a hybrid.

Is Amerisleep safe to use?

Amerisleep beds are non-toxic and made with CertiPUR-US® foams, which means they meet rigorous health and safety standards.

Is Amerisleep made in America?

Yes, all Amerisleep beds are made in America.

Does Amerisleep have fiberglass?

All Amerisleep mattresses are produced without fiberglass, which is sometimes used in mattresses and can be harmful if released.

Want to learn more? Read our in-depth guide on fiberglass in mattresses.

Amerisleep AS4 vs Other Brands

Amerisleep AS4 vs Puffy

Amerisleep AS4 Mattress
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  • 12-inch profile
  • 6/10 firmness
  • Open-cell foam
Puffy original mattress product image
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  • 10-inch profile
  • 5.5/10 firmness
  • Gel-infused cooling foam

Who We Recommend the Amerisleep AS4 For

  • Eco-conscious shoppers
  • Those who like a responsive mattress
  • People who prefer foam with a gentle cradle rather than a deep hug

Who We Recommend the Puffy For

  • People who want a removable, washable cover
  • Hot sleepers
  • Those who prefer a lifetime warranty

Read our Puffy mattress review if you think the Puffy is right for you.

Amerisleep AS4 vs Cocoon Chill Memory Foam

Amerisleep AS4 Mattress
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  • 6/10 firmness
  • 12-inch profile
  • 20-year warranty
product image of cocoon chill
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  • 6/10 firmness
  • 10-inch profile
  • 10-year warranty

Who We Recommend the Amerisleep AS4 For

  • Hot sleepers
  • Couples looking for a responsive foam mattress for sex
  • Lightweight side sleepers

Who We Recommend the Cocoon Chill Memory Foam For

  • Average-weight combination sleepers
  • Those requiring great edge support
  • Shoppers on a smaller budget

Read our Cocoon Chill Memory Foam mattress review if you think the Cocoon Chill Memory Foam is right for you.

Amerisleep AS4 vs Other Amerisleep Models

Amerisleep AS4 vs Amerisleep AS3 Hybrid

Amerisleep AS4 Mattress
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  • Five-zoned support
  • 6/10 firmness
  • All-foam
Product image of AmeriSleep AS3 Hybrid
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  • Three-zoned support
  • 5.5/10 firmness
  • Hybrid

Who We Recommend the Amerisleep AS4 For

  • Those who prefer a balanced foam feel
  • Side sleepers looking for enhanced pressure relief
  • People who require more targeted support

Who We Recommend the Amerisleep AS3 Hybrid For

  • Hot sleepers
  • Shoppers seeking a traditional hybrid
  • People requiring exceptional edge support

Read our Amerisleep AS3 Hybrid mattress review if you think the Amerisleep AS3 Hybrid is right for you.

Amerisleep AS4 vs Amerisleep AS2

Amerisleep AS4 Mattress
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  • All-foam
  • 12-inch profile
  • 6/10 firmness
Product image of Amerisleep AS2 mattress
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  • All-foam
  • 12-inch profile
  • 6-7/10 firmness

Who We Recommend the Amerisleep AS4 For

  • Side sleepers
  • Lightweight sleepers
  • People who prefer a slightly plusher mattress

Who We Recommend the Amerisleep AS2 For

  • Stomach sleepers
  • Back sleepers
  • Budget shoppers

Read our Amerisleep AS2 mattress review if you think the Amerisleep A2 is right for you.

Overall Summary

The Amerisleep AS4 is an all-foam mattress that’s ideal for side sleepers, especially those seeking a mattress with eco-friendly qualities.

Side Sleeping Icon

Side Sleepers


The Amerisleep AS4 is great for side sleepers, as it does a fantastic job at providing exceptional pressure relief along with great spinal support. However, side sleepers weighing more than 300 pounds will likely find themselves sinking too deeply, which could cause pressure buildup. We gave it a 5, though, as it will still accommodate many plus-size sleepers.

Back Sleeping Icon

Back Sleepers


Back sleepers weighing up to 200 pounds should find themselves sleeping comfortably on this mattress, experiencing a good balance of pressure relief and spinal support. However, those over 200 pounds will likely find themselves bottoming out in the soft layers, which will take their spine out of alignment, causing aches and pains over time.

Stomach Sleeping Icon

Stomach Sleepers


The Amerisleep AS4 is softer than average, which doesn’t make it a good choice for most stomach sleepers, who will require a lot more support, which they’d get from a firmer mattress. Having said this, some exceptionally lightweight people may find the level of support is adequate enough to keep their hips raised.

Combination Sleeping Icon

Combination Sleepers


Light to average-weight combination sleepers who switch between their side and back should find this mattress pretty comfortable, as it supports both those positions and has enough bounce to stop you from feeling ‘stuck’ in the foam. This should allow you to change positions with ease.

Couples Icon



This slightly soft mattress may not be the best pick for couples with wildly different weights and sleeping preferences, and while its edge support is okay, it’s not the best we’ve experienced, which is why it earned a 3. However, it does feature cooling technology, responsiveness, and motion isolation, all of which many couples could appreciate.

Heavy Sleepers Icon

Heavy Sleepers


In general, this isn’t a great choice for heavyweight folk, as it’s far too soft. However, strict side sleepers weighing between 230 – 300 pounds should find it provides a good balance of pressure relief and support. Back sleepers, stomach sleepers, and side sleepers above 300 pounds would find better support on a mattress designed for heavier sleepers.

Light Weight Sleepers

Lightweight Sleepers


Lightweight back and side sleepers should find this mattress a real treat, with the five-zoned foam offering pressure relief and support in all the right areas. While exceptionally lightweight stomach sleepers may find it supportive enough, we think most would be better off on a firmer mattress, which will help keep the spine in healthy alignment.

Light Weight Sleepers

Average Weight Sleepers


Average-weight side sleepers should find themselves sleeping comfortably on this mattress, with its great pressure relief and spinal support. Most back sleepers should also find it a dream, but those over 200 pounds will likely require a firmer mattress. We don’t recommend the Amerisleep AS4 for stomach sleepers, who will need something firmer to keep the hips raised.

Overall Value


This mattress comes with a longer 20-year warranty to back up its durability, and the 100-night trial meets the industry standard. We also like that it’s a more eco-conscious design, and the company offers free shipping and returns for customers. Overall, we think this bed is a good value.

Our Verdict

If you’re a side sleeper or light to average-weight back sleeper who’s looking for a bed with cooling technology, planet-friendly features, and exceptional pressure relief, you may well have hit the jackpot with the Amerisleep AS4. It’s not the cheapest all-foam bed on the market, but its durable construction should have you sleeping comfortably for years, making it a sound investment toward better sleep.

If you’re a plus-size sleeper or someone who strictly sleeps on their stomach and like the sound of Amerisleep, you should check out one of their firmer models, like the AS1 or AS2.

Amerisleep AS4 Mattress
Get the Amerisleep AS4 Mattress
An all-foam, pressure-relieving bed made with side sleepers and eco-conscious shoppers in mind.
Click the button below to get the Amerisleep AS4 Mattress.
Lisa Bowman
Lisa Bowman

Lisa is a content writer for Sleep Advisor, which combines two of her greatest passions – writing and sleeping. She can also be found writing about fitness, sustainability and vegan food.

Her life revolves around her two rescue dogs (who she shares her bed with) and if she’s not running around after them, she’s likely doing yoga, buying new plants, or enjoying a sunset rum at the beach.

Writing for Sleep Advisor has made her realise she needs a new mattress, stat.

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