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AS4

Starting at $1449  $1249
Available in 7 sizes
AS4
MEDIUM SOFT FEEL Profile height: 12-inch

Risk-free, 100-night trial

20-year warranty

Free shipping & returns

Made in USA

AS4

Why you'll love it
Benefits
Bonuses

Experience cloud-like comfort with the medium-soft AS4. Designed with a deeper top layer of pressure-relieving foam, our AS4 offers extra cushion for side and combo sleepers.

  • Experience cooling comfort with our plant-based Bio-Pur® memory foam
  • Maximize airflow and targeted support with our exclusive HIVE® technology
  • Prevent sagging and uncomfortable sinkage with our durable base foam
  • Free, no contact fast shipping
  • 100-night, risk-free sleep trial
  • Easy and free returns
  • 20-year warranty
  • Mattress made in the USA
  • Twin (38" x 74") $1449
  • Twin XL (38" x 80") $1499
  • Full (54" x 75") $1649
  • King (76" x 80") $2099
  • Queen (60" x 80") $1799
  • California King (72" x 84") $2099
  • Split King (38" x 80" - 2) $2998
Amerisleep foundation
Amerisleep Platform Bed

Perfectly support your mattress

+ $275
$1799 $1599 with promo
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Better sleep through better design

Sleep Cooler

Sleep Cooler

Comfort You Will Love

Comfort You Will Love

Tested to Last

Designed to Enhance Sleep

More Support, Deeper Sleep

Alleviates Pressure Points

Eco-Friendly Production

Eco-Friendly Production

Stays cool all night

Our plant-based Bio-Pur® material keeps you cool all night. It features an open-cell design that allows more air to escape than traditional foam.

Moon icon

Open-cell design wicks away warm air

Wind icon

More breathable than traditional foam

Experience Bio-Pur®:
Eco-Friendly, Cooler Memory Foam

Bio-Pur® is the perfect answer to a better bed. Available in every Amerisleep mattress, we engineered Bio-Pur® to deliver cooling comfort, responsive support, and healthier sleep.

Memory foam lovers say Bio-Pur® is a huge upgrade, while critics admit it solves all the problems of traditional memory foam. Plus, since our beginnings in 2009, we've proudly manufactured Bio-Pur® in the USA.

Bio-Pur® vs Traditional Memory Foam

Breathable & Cooling

Bio-Pur®'s large, open-cell structure has a few distinct advantages:

  • Allows air to flow freely
  • Prevents heat build-up
  • Perfect for hot sleepers

Responsive & Supportive

Unlike traditional memory foam, Bio-Pur® has a rapid response time that:

  • Relieves painful pressure points
  • Prevents heat build-up
  • Bounces back in just seconds

Eco-Friendly Materials

Featuring renewable plant-based oils, Bio-Pur® helps us:

  • Minimize use of non-renewable resources
  • Prevents heat build-up
  • Produce products that are better for you and the planet

A Healthier Sleep

The surface you sleep on is important. That’s why Bio-Pur® is:

  • CertiPUR-US® certified & low in VOCs
  • Resistant to dust mites, mold, and mildew & made without harsh chemicals

Traditional memory foams miss the mark when it comes to cooling and responsiveness. Amerisleep’s proprietary Bio-Pur® memory foam is an eco-friendly alternative that blends contouring comfort with buoyant support and superior breathability to help you get your best night’s sleep yet.

Our plant-based Bio-Pur® is significantly more breathable and responsive than traditional memory foam. It snaps back to its original shape in seconds, so it’ll never cause you to uncomfortably sink, and it’s significantly more porous and airy, so you won’t have to worry about night sweats. Even better? Bio-Pur® contains a fraction of the petrochemicals used in other memory foams, so it’s less likely to off-gas and is completely free of harmful substances.

That’s why in over 15,000 reviews, our mattresses rate 4.7 out of 5 stars and why 98% of customers would recommend us to a friend.

See why our customers love Bio-Pur®

All
Breathable
Comfortable
Responsive
Supportive
  • All
  • Breathable
  • Comfortable
  • Responsive
  • Supportive

Relieves pain & pressure points

Our Bio-Pur® comfort layer contours to your body and relieves pain-causing pressure points. But it also bounces back fast, so you never feel “stuck” if you move around at night.

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Soothing pressure point relief

Pressure point icon

More responsive than traditional foam

Crafted for lasting comfort

We make our mattresses here in America with the highest quality craftsmanship. They’re built to last and backed by a two-decade warranty.

Warranty icon

Industry-leading 20-year warranty

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Won’t sag or develop soft spots

Made with side sleepers in mind

Our medium-soft mattress offers plush comfort with targeted support that helps you sleep your best.

Amerisleep AS4 mattress cover Amerisleep AS4 mattress layers
Ultra-Breathable Comfort

Our soft and ultra-breathable covers help prevent overheating, so you can sleep your best each night.

Stays Cool & Never Feels “Stuck”

Bio-Pur®’s open-cell design keeps you cooler than traditional foam. It also contours to your body to relieve pressure points and bounces back fast, so you won’t feel “stuck”.

Targeted Pressure-Relief System

Our HIVE® transition layer provides targeted support and pressure relief so you can sleep in perfect alignment. It gives your head, back, and legs more support, and your shoulders and hips more cushion.

Durable Support for Decades

The Bio-Core® base layer gives you durable support that lasts for decades. It won’t sag or develop soft spots over time. (And we prove it with our 20-year warranty.)

Sleep in perfect alignment

Our HIVE® transition layer gives your body targeted support to ease tension and help you sleep in perfect alignment. It provides added support under your head, back, and legs. And it gives your shoulders and hips extra cushion. We’ve also designed HIVE® to reduce pain-causing pressure points.

Enjoy deeper sleep and more daily energy. Try the AS4 for 100 nights.
100 Night Trial
Risk-free, 100-night trial
with free shipping & returns

Specifications

 
Available sizes
(inches)
  • Twin 38" W x 74" L x 12" H
  • Twin XL 38" W x 80" L x 12" H
  • Full 54" W x 75" L x 12" H
  • Queen 60" W x 80" L x 12" H
  • King 76" W x 80" L x 12" H
  • Cal King 72" W x 84" L x 12" H
  • Split King 38" W x 80" L x 12" H (x2)
 
Free Shipping

Amerisleep Mattresses come with free shipping within the continental US. We ship our mattresses direct to your home and compressed in an eco-friendly box using FedEx. And in most cases, they arrive in two weeks or less.

Please note: All our products ship separately, so if you’ve ordered a foundation, base, sheets, or any other sleep accessories to go with your new mattress, they may arrive sooner or later than your Amerisleep mattress. But don’t worry, shipping is always free.

 
20-Year Warranty

Amerisleep mattresses are backed by an industry-leading 20-year warranty. For the first 10 years, we will replace your mattress if you encounter any defects, including sagging greater than 0.75”. And for the second 10 years, we will offer you a prorated replacement.

 
Compatibility

Our mattresses are compatible with a variety of bed frames and bases.

Mattress Foundations
Our memory foam and hybrid mattresses are best supported on solid or slatted mattress foundations. Slatted bases should have slats no more than 3 inches apart — we even sell our Amerisleep Mattress Foundation designed to pair perfectly with our mattresses.

Platform Beds
Platform beds have a solid or slatted base, so they can provide proper support for our mattresses. If you have a platform bed with large gaps between slats, we suggest buying extra slats or a bunkie board to create a sturdier surface for your mattress and meet warranty guidelines.

Adjustable Bed Frames
Our memory foam mattresses work well with adjustable bed frames. They’re adaptable and flexible, so they can move with the base without becoming damaged or worn. We even sell two adjustable bed frames to pair with our beds: the Amerisleep Adjustable Bed and the Amerisleep Adjustable Bed+.

While our mattresses can work with most bed frames and foundations, it’s not compatible with absolutely every type of mattress support — namely box springs.

Box Springs
Box springs are best paired with innerspring mattresses, and since innerspring beds were the most common for many years, a lot of us have box springs at home. Box springs contain coils within and as a result, are bouncy. Beds with foam layers can experience premature wear, tear, and unexpected damage when paired with one of these because they do not offer the even, sturdy support foam beds need.

Upgrade your mattress with our complete sleep system

Amerisleep pillow
Go ahead and relax

Shop our lineup of pillows engineered for better head and neck support.

Browse Pillows
Amerisleep bedding
Wrap yourself in luxury

Explore our suite of bedding options designed for exceptional softness and comfort.

Browse Bedding

See what our satisfied sleepers have to say

All reviews are unaltered and verified by a 3rd party.

*Reviews

All featured customer reviews are unaltered and verified by a third-party. The comments made by customers are not intended as advertisements, and should be understood as the perspective of each individual based on their experience. These reviews should not be construed to mean that these experiences are universal or that results will always be the same.

Frequently Asked Questions

 
Is the cushioning Amerisleep AS4 still supportive?

Yes, our AS4 mattress is supportive from its top layer of Bio-Pur® foam to its middle and base foams:

  • The comfort layer of Bio-Pur® responds to your every movement to limit sinkage, keeping your spine from bowing so far into the mattress that you misalign your back.
  • The middle layer is Affinity foam with HIVE® technology, which features five support zones so that it’s soft where you want it and firm where you need it. The head, back, and feet areas have a less flexible feel to create more support.
  • The base layer is Bio-Core® foam, a material that’s so durable and sag-resistant that it’s the main reason why we can offer a 20-year warranty.
 
Who are medium-soft mattresses good for?

Medium-soft mattresses are excellent for side sleepers who want a soft mattress that isn’t too soft. They can sink into the mattress just enough to appreciate its cradling cushion but won’t sink so far that they develop back pain.

A medium soft mattress is also a good choice for people under 130 pounds. Smaller sleepers often don’t place enough pressure on their mattress’s surface to experience full-body cushion and pain relief on firmer mattresses.

 
Is the AS4 cooling enough for sleepers with night sweats?

Yes, the AS4 mattress promotes a cool sleeping surface with its temperature-regulating cover and its airy top foam layer. The entire mattress is covered with a soft, breathable fabric to ensure air flows through the bed and wicks away accumulated heat. The top layer of Bio-Pur® foam has an open-cell structure to promote heat dispersion.

 
What bed frames/mattress foundations can I pair with the AS4?

Our AS4 mattress can be paired with almost any solid or slatted base. You can use a wooden mattress foundation, a panel bed frame, a platform bed, and an adjustable bed base. If you use a slatted surface, make certain the slats are at least 0.75 inches thick and no more than 3 inches apart.

Do not place the AS4 or any of our mattresses directly on top of a box spring. A box spring cannot provide a consistently even surface and will leave gaps that allow a mattress to sag prematurely.

 
What does the AS4’s CertiPUR-US® certification mean?

A CertiPUR-US® certification means that a third-party organization has overseen our foam production process and deemed the mattress’s materials safe. A CertiPUR-US®-approved mattress is produced without:

  • Formaldehyde
  • Mercury, lead, and other heavy metals
  • Ozone depleters
  • PBDEs, TDCPP or TCEP flame retardants

A CertiPUR-US® certified mattress also has low amounts of volatile organic compounds (VOCs). Fewer VOCs means the mattress is less likely to off-gas, which is the process behind a funky and lingering “new mattress smell.”

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