The Amerisleep AS4 mattress is one of the softer mattresses from the series of memory foam beds by Amerisleep. It’s built with three layers of memory foam that are softer and more cooling than the AS1, AS2, and AS3 mattresses.

Amerisleep has five options in their line of memory foam mattresses that range from firm to soft and are designed to fit different sleeping positions.

The Amerisleep AS4 is the second-softest mattress they have. It is called “medium-soft” and is made specifically for side sleepers.

This review will cover everything people need to know about the Amerisleep AS4 mattress, including a full breakdown of the construction, firmness and feel, comfort, support, motion isolation, edge support, breathability, durability, and so much more.

To learn more about this bed, keep reading our in-depth Amerisleep AS4 mattress review.

AmeriSleep AS4 Mattress

The Amerisleep AS4 mattress is one of the softer mattresses from the series of memory foam beds by Amerisleep. It’s built with three layers of memory foam that are softer and more cooling than the AS1, AS2, and AS3 mattresses.

$1499 with promo $1699

A look at the Amerisleep AS4 mattress

The AS4 is Amerisleep’s medium-soft mattress billed as best for side sleepers. It comes in 7 sizes ranging from Twin to Split King. This foam mattress is made up of 3 core layers and a removable Celliant-blend fabric top cover. It has built-in cooling features including the addition of a transition layer. The mattress is manufactured in the US.


The three main layers together with the cover measure 12 inches total and consist of the following:

  • Base layer: The foundation of the mattress is a 7” support layer of high-density poly foam. This layer provides the compression support and shape of the mattress and balances out the body contouring and softness of the comfort layer. Amerisleep refers to their high-density foam as Bio-Core foam.
  • Mid layer: The center transition layer provides 1” of convoluted foam. This layer is zoned to provide extra support in the shoulder area and lower back region. Its channels ensure airflow and temperature regulation.
  • Top layer: The 4” top layer consists of Bio-Pur memory foam for pressure relief, body contouring, and temperature control. The company describes this as an open-celled, breathable memory foam, which adds another cooling feature.

Brief Overview

The Amerisleep AS4 offers cooling properties in two of its three layers. The top layer is proprietary plant-based memory foam, which sleeps much cooler than traditional synthetic foam. It undergoes a process called reticulation, where the cell walls of the foam are blown out while the foam shape remains intact, which makes the top layer much more breathable. The middle layer’s surface contains breathable channels that promote higher airflow.

Delivery & Off-Gassing:

Like all other Amerisleep mattresses, the AS4 is shipped for free. The mattress is made right here in the US, compressed, rolled up, and then fit into a compact box. Your AS4 should arrive within a week via FedEx. The white and blue box will be the dreamiest thing that has ever arrived at your door.

The first thing you will want to do is to get the mattress to its desired location. Then, remove it from the box, set it on its base, and cut away the plastic. The initial expansion will only take a few minutes, but you will need to allow 24-48 hours before your mattress has firmed up to its true feel. This means you may not want to sleep on it the first night, or at least don’t expect it to be at its 100% firmness level yet.

Most boxed mattresses will have a unique smell, but you can just consider this the ‘new’ mattress smell because any fumes that are present are non-toxic and harmless. Since the AS4 is made in the US and Amerisleep strives to use more environmentally friendly materials, you know there won’t be any noxious fumes. If you’re sensitive to new smells or don’t prefer it, simply open a window and let the mattress air out while it is expanding. This will be perfect timing for both to occur and you don’t have to stay in the same room, so you can avoid the smell.

Amerisleep AS4 Mattress – Comfort:

There is a reason the AS4 is one of the most popular choices of the Amerisleep brand. The medium-soft feel is the perfect blend of plush and support, so once you’re in bed, you’re in bed and surrounded by comfort. This mattress is ideal for a variety of sleepers, but especially side sleepers, couples with a softer comfort preference, and those who like a little extra softness to their mattress.

The AS4 perfectly relieves pressure points, but it’s the fast response time that is top-notch. The unique foams used by Amerisleep promise to recover their shape faster than traditional memory foams. Most memory foams take about 60 seconds to bounce back, but the Amerisleep foams take only 4 seconds. That means you can get comfier faster, the mattress conforms to you faster, and you feel less “stuck”.

Not to mention the Affinity layer makes you feel like you’re floating, so you’re truly never stuck. With the Bio-Core foundation layer, you’ll never float away and still get all the support you need thanks to this dense, firm layer. The added bonus with the AS4 is its medium-soft, so you get just a little extra softness for comfort. And there’s no such thing as too much comfort!

In addition, the cover contains Celliant, which is known to reduce pain, regulate body temperature, and promote healthy blood circulation.

Amerisleep recommends this mattress most highly for side and combo sleepers, with a medium-soft supportive feel.

Trial Period & Warranty:

As mentioned above, you get 100 nights to test the AS4 and a 20 year warranty. Both of these values are Amerisleep’s promise to giving you your best night’s sleep. Four months is more than enough time to decide if the AS4 is the best fit for you. We recommend however that you at least give yourself 30 days to try it before you return it. This allows enough time for the foams to settler and for you to get a true feel of the mattress. After that, if you’re still not satisfied, Amerisleep will help you make a fast and easy return.

Remember, the first 10 years of the warranty are completely covered, but after that it is prorated to coincide with the natural wear and tear of the mattress. Still, with 20 years being longer than most, you know you’re buying from a company that stands behind their product.

Amerisleep AS4 Mattress Review

Amerisleep AS4 mattress

The Amerisleep AS4 mattress is a medium-soft mattress offered by Amerisleep. This bed is great for side sleepers and those who tend to sleep hot.

AmeriSleep AS4 Mattress

The Amerisleep AS4 mattress is one of the softer mattresses from the series of memory foam beds by Amerisleep. It’s built with three layers of memory foam that are softer and more cooling than the AS1, AS2, and AS3 mattresses.

$1499 with promo $1699

It’s built with three layers of memory foam, including Amerisleep’s proprietary, cooling Bio-Pur® and HIVE® comfort layers. These layers are intended to create a soft and responsive feel so you can sink in the mattress enough to be comfortable, but no such much that you can’t move around.

The design of the AS4 also makes it great at relieving pressure, another important factor for side sleepers. Instead of letting you sink in too far and build up pressure in your hips and shoulders, the Amerisleep AS4 evenly distributes your body weight to avoid pain in the pressure points.

Top this all off with the high-performance Celliant® cover made with Thermo-reactive yarn and you truly have a great bed. This cover design safely turns your body heat into infrared energy to help wick away heat and keep you cool in your sleep.

AmeriSleep AS4 Mattress

The Amerisleep AS4 mattress is one of the softer mattresses from the series of memory foam beds by Amerisleep. It’s built with three layers of memory foam that are softer and more cooling than the AS1, AS2, and AS3 mattresses.

$1499 with promo $1699


Customer Reviews

See what actual customers have to say about the Amerisleep AS4 mattress.

  • “I love the firmness, yet it gives to mold to my body and it is not hot like others have complained about with other memory foam mattresses.” – Katy
  • “Hubby and I have used this mattress for over a year now and still wouldn’t exchange it for another. We have slept better and have less aches and pains since it arrived. It has kept me cooler than our last bed.” – Sleep Addict
  • “I used to wake up every morning with back pain so I was looking for a mattress that would eliminate my pain, but it had to be firm enough for my husband and not too firm for me. This is my first memory foam mattress and it’s perfect! You don’t feel like you’re sinking into the mattress but it also doesn’t feel too hard. I’m also much cooler at night. Great mattress…I’d recommend for anyone!”
  • AmeriSleep AS4 Mattress

    The Amerisleep AS4 mattress is one of the softer mattresses from the series of memory foam beds by Amerisleep. It’s built with three layers of memory foam that are softer and more cooling than the AS1, AS2, and AS3 mattresses.

    $1499 with promo $1699


Product Information

WEIGHT

94 lbs. for queen

THICKNESS

12″

FIRMNESS

Medium soft: 4/10

TYPE

Memory foam

AMERICAN MADE

Made in the USA

Compatible Foundations

Amerisleep recommends a flat surface for the AS4. You can use a flat or slatted frame, box spring with plywood, adjustable base or even set it on the floor.

AmeriSleep AS4 Mattress

The Amerisleep AS4 mattress is one of the softer mattresses from the series of memory foam beds by Amerisleep. It’s built with three layers of memory foam that are softer and more cooling than the AS1, AS2, and AS3 mattresses.

$1499 with promo $1699

What’s Inside the AS4 Mattress?

The layers inside the Amerisleep AS4 are described as they appear from top to bottom:

  • High-performance Celliant cover: Designed to convert your body heat into infrared.
  • Bio-Pur foam: Breathable cooling layer with an open-cell structure
  • Affinity layer: Ergonomic transition foam; provides pressure relief
  • Bio-Core foam support layer: Eco-friendly durability and support

Purchase Information

Purchase Experience

PolicyDetails
DeliveryCompressed and rolled in a box that is 19” x 19” x 42” for a queen
Trial Period100 days
Warranty20-year limited warranty
Return PolicyFull refund on returns within 100-day trial period
FinancingNot available

Sizes and Pricing

AmeriSleep AS4 Mattress

The Amerisleep AS4 mattress is one of the softer mattresses from the series of memory foam beds by Amerisleep. It’s built with three layers of memory foam that are softer and more cooling than the AS1, AS2, and AS3 mattresses.

$1499 with promo $1699

SizeDimensionsStandard Price*
Twin38″ x 74″$1,399
Twin XL38” x 80”$1,499
Full54” x 75”$1,549
Queen60” x 80”$1,699
King76” x 80”$1,899
Split King38″ x 80″ (x2)$2,698
Cal King72” x 84”$1,899
9.9 Total Score
AmeriSleep AS4 Mattress

The Amerisleep AS4 mattress is one of the softer mattresses from the series of memory foam beds by Amerisleep. It’s built with three layers of memory foam that are softer and more cooling than the AS1, AS2, and AS3 mattresses.

Delivery & Unboxing
9.6
COMFORT
9.8
MOTION TRANSFER
9.9
Sleeping Cool
9.9
Edge Support
9.3
Materials & Construction
9.6
PROS
  • Full-spectrum firmness levels to suit every sleeping type
  • Experience all the benefits of memory foam without sleeping too hot
  • Isolates motion plus decent edge support, which is good for couples
  • Materials are eco-friendly and certified by CertiPUR-US®
  • The foams are plant-based, not made of petroleum
  • Free shipping and free returns in the continental United States
  • Made in the USA
CONS
  • Customer concerns about the durability of the foam
  • May not hold up to long-term wear like you might expect for the price
  • Not for heavier sleepers who put more pressure on the foam
User Rating: 4.5 (2 votes)