Amerisleep and Casper are making some of the best foam mattresses available today, providing users with comfortable and peaceful sleeps each and every night. Many mattress shoppers hesitate between these two brands, but our Amerisleep vs. Casper guide should help you make the right decision. For the purposes of this comparison and buying guide, we focused on the most popular mattress models from each brand: the AS3 from Amerisleep and the latest version of the flagship Casper 12-inch. Highly versatile and universally comfortable, these are some of the best memory foam mattresses you can buy.
The Amerisleep and Casper mattresses have plenty in common in terms of their firmness rating, with both of these mattresses being rated at 5.5. They’re also the same thickness, with both being 12 inches, but do have some key differences in terms of their construction, and the Casper mattress is much cheaper overall.
5.5 firmness rating
Thickness of 12 inches
Features a three-layer design
7 inches of support foam, 2 inches of polyfoam, and 3 inches of memory foam
Comes with a 20-year warranty and 100-night trial
5.5 firmness rating
Thickness of 12 inches
Much more affordable
Features a four-layer design
7 inches of support foam, 1.5 inches of additional polyfoam, 1.5 inches of memory foam, and then a final layer of latex-like foam
As the table above shows, we can see a few key differences in terms of the construction of these two memory foam mattresses. The triple-layer memory and polyfoam combo, combined with a thick later of supporting polyfoam, seen on the Casper provides a different feel to the Amerisleep, which is made up of two layers of supporting polyfoam and then a final 3-inch-thick layer of memory foam. The covers are different too, with the Casper sporting a standard polyester cover, while the Amerisleep features a more advanced and breathable cover.
The comfort of a mattress is the thing that matters the most to the end user, but when talking about comfort for Amerisleep vs Casper, there are a lot of individual factors to think about. We have to take multiple aspects into consideration, including the firmness of each mattress, any traces of off-gassing or odor, how well they handle motion transfer, and more.
Firmness and support
Both the Amerisleep and Casper mattresses are rated as 5.5 or Medium in terms of firmness. This would suggest that they both feel quite similar to sleep on, and they are almost identical in terms of softness, but they do differ slightly. The thicker layer of memory foam seen on the Amerisleep mattress gives it more of a hugging, contouring quality than the Casper. So if you like that classic memory foam feel, you might prefer the Amerisleep over the Casper.
In terms of temperature neutrality, the Amerisleep makes use of a polyester, Spandex, and Celliant cover in order to offer more breathability and a stronger cooling effect than the standard polyester cover seen on the Casper. However, the Casper still sleeps quite cool thanks to its layer of latex-like foam, which gives less of a close-contouring effect for the sleeper.
The motion transfer on the Amerisleep is excellent. It’s one of the best memory foam mattresses around right now in terms of absorbing motion and ensuring that couples sleep peacefully without disturbing each other. Similarly, the Casper has gotten great user reports and reviews in regard to motion isolation, so there’s no real difference between the mattresses in this aspect.
Many memory foam mattresses aren’t particularly responsive, and this is the case with both the Casper and the Amerisleep. The thicker layer of memory foam used on the Amerisleep makes it a little slower to respond than the Casper overall.
Resilience and bounce
As seen above for Responsiveness, both the Amerisleep and Casper mattresses aren’t particularly bouncy. However, the latex-life foam and reduced amount of memory foam seen in the Casper makes it a little bouncier, which is something that couples may appreciate.
A lot of memory foam mattresses struggle to provide decent edge support, and we can see a clear example of this with the Casper. This mattress offers minimal support around the edges, and it’s easy to sink into it and feel like you’re about to slip off if you sit on the side. The Amerisleep, however, offers surprisingly decent edge support for a foam mattress.
Inflation time, off-gassing and smell
You’ll need to leave your new Casper or Amerisleep mattress around 24 hours to let it air out and inflate before use. In terms of off-gassing, users have reported some odors with the Casper that can be quite noticeable at first but fade in the first week. With the Amerisleep, minimal or zero off-gassing and odor can be expected.
Sleep position ratings
Light sleepers (less than 130 lbs)
Average sleepers (130 lbs to 230 lbs)
Heavy sleepers (greater than 230 lbs)
*Out of 10
This table gives us an indication of how comfortable you’ll find each mattress depending on your body type and sleeping style. We can see that average and heavier sleepers tend to favor the Amerisleep mattress, which is also better overall for stomach and back sleepers, as well as combo sleepers. The Casper, meanwhile, performs well for light sleepers and side sleepers, but struggles with stomach sleepers.
Sizes and pricing
Warranty and refund
20-year warranty full refund
All 48 contiguous states
10-year warranty full refund
Within the U.S. and Canada
Both Amerisleep and Casper mattresses come with a 100-night sleep trial. This is the standard for the industry and the minimum a buyer would expect when purchasing a high quality new mattress from a leading company.
Warranty and refund
In terms of warranty and refund, we can see a clear winner in this battle of Casper vs Amerisleep. The Casper mattress comes with a 10-year warranty, which is the industry standard, but you’ll have to pay the shipping fees if you need a refund on the mattress. The Amerisleep mattress, meanwhile, comes with a strong 20-year warranty, which is one of the longest you can hope to find on a new foam mattress.
While Amerisleep may have won the warranty battle, Casper takes the crown for delivery. Casper mattresses are currently available all over the United States and also north of the border in Canada. For now, Amerisleep mattresses can only be delivered in the 48 contiguous states.
We can see that both Amerisleep and Casper mattresses have their plus points and their drawbacks, and the mattress you choose will ultimately depend on your own needs, budget, and sleeping style. Neither mattress is objectively better than the other, but each one is better-suited for certain people.
In terms of pure comfort and versatility, the Amerisleep is the stronger mattress. It gets better ratings for most kinds of sleeper and also offers that classic memory foam feel that so many people crave. It excels in terms of edge support too, and it has minimal off-gassing and almost no odor in most cases.
The Casper, meanwhile, has the advantage of faster responsiveness and better bounce, making it a more popular choice with people who desire these aspects in their mattresses. It’s also a better option for light and side sleepers, though it does demonstrate slightly week edge support and a little off-gassing too.
The Amerisleep is the more expensive mattress of the two, so if you’re shopping for a high quality mattress on a budget and want something that offers good performance and comfort levels without breaking the bank, the Casper is the smarter choice. If you’re willing to pay the extra cash for a little additional comfort, the Amerisleep will most likely win out for you. Overall, for Casper vs Amerisleep, there’s no clear winner, and both mattresses are very comfortable and exceptionally well-made.