by Top Recommendation
Amerisleep AS3 — Best Memory Foam Mattress
Plant-based Bio-Pur open-cell foam that runs cooler than petroleum all-foam, paired with the HIVE 5-zone lumbar layer. Our top-rated all-foam pick for side and back sleepers in 2026.
The best memory foam mattress is the Amerisleep AS3. Its plant-based Bio-Pur open-cell foam tests cooler than any petroleum-based all-foam we have measured, and the HIVE 5-zone layer firms directly under the lumbar so both side and back sleepers stay aligned. The Saatva Loom & Leaf is the right call for anyone who wants a 365-night trial and a denser, more durable foam construction.
Amerisleep AS3
9.4/10
- Plant-based Bio-Pur open-cell foam: cooler than petroleum all-foam in our 8-hour thermal test
- HIVE 5-zone support layer firms under the lumbar, softer at shoulders and hips
- CertiPUR-US certified, made in the USA, 20-year warranty
- Best motion isolation in this guide: 9.5/10 on our wine-glass rig
- Edges compress more than a hybrid at 180 lb (4.2 in. sinkage)
- Sleepers over 250 lb should size up to the AS5 Hybrid
The AS3 wins on cooling, pressure relief, and lumbar alignment at a price that undercuts most luxury all-foam alternatives. It is the most complete memory foam pick for side and back sleepers under 230 lb.
How We Test
Every mattress here was purchased at retail, slept on for at least 30 nights by three testers (side, back, combo), and measured with a Tekscan pressure-mapping mat, a thermal camera, and a wine-glass motion-isolation rig. Scores weight pressure relief 30%, support 25%, cooling 15%, motion isolation 15%, edge support 10%, value 5%.
Best memory foam mattresses at a glance
The Amerisleep AS3 earns the top spot because its plant-based Bio-Pur foam tests cooler than any petroleum-based all-foam in our lab, and the HIVE zoned layer delivers real lumbar alignment. The Saatva Loom & Leaf is a stronger pick for heavier sleepers or anyone who sleeps hot and wants a luxury feel; the Avocado Green is the right call for organic-certified buyers who need a firmer, more responsive surface. All prices below are queen-size.
| Mattress | Type | Firmness | Score | Trial / Warranty | Price (queen) |
|---|---|---|---|---|---|
| Amerisleep AS3 | All-foam (Bio-Pur) | Medium (5/10) | 9.4 | 100 nights / 20 yr | From $1,049 |
| Saatva Loom & Leaf | All-foam (gel memory) | Medium / Firm (5 or 7) | 9.1 | 365 nights / Lifetime | From $1,795 |
| Puffy Original | All-foam (gel-infused) | Medium (5/10) | 8.5 | 101 nights / Lifetime | From $749 |
| Avocado Green | Latex hybrid (Dunlop) | Medium-Firm (6/10) | 9.0 | 365 nights / 25 yr | From $1,399 |
| Amerisleep AS5 Hybrid | Hybrid (Bio-Pur + coils) | Medium-Soft (4/10) | 9.2 | 100 nights / 20 yr | From $1,799 |
#1 Amerisleep AS3: what 90 nights of testing showed
The AS3 is a 12-inch all-foam bed with three layers: 3 inches of Bio-Pur plant-based foam on top, 2 inches of Affinity with HIVE hexagonal zoning in the middle, and a 7-inch Bio-Core high-density base. The plant-based foam has an open-cell structure that moves air more freely than a closed-cell petroleum foam, and you feel the difference by around the third week.
On the pressure-mapping mat, our side-sleeping tester recorded 32 mmHg at the shoulder and 28 mmHg at the hip, both well under the 35 mmHg threshold that typically indicates pain risk. Back-sleeping alignment scored 9.2 out of 10. Motion isolation was so good that the wine glass never so much as trembled at 12 inches from a dropped weight.
The one place it gives up ground is the perimeter. All-foam edges compress by 4.2 inches under 180 lb, noticeably more than a hybrid with reinforced coil edges. If you sit on the edge of the bed daily, or sleep with a partner who pushes toward the margin, that compression is something to factor in.
#2 Saatva Loom & Leaf: the case for a longer trial window
The Loom and Leaf uses a 5 lb high-density gel memory foam topped with a gel-infused pillow top and wrapped in spun organic cotton. That combination keeps surface temps within 2 degrees of ambient in our 8-hour thermal camera test, which is a solid result for a memory foam mattress at this density.
The 365-night trial is a genuine differentiator. Most mattress trials run 100 nights, which covers the first impression but not the medium-term body-adaptation window. Saatva's year-long trial gives you four seasons to decide. The lifetime warranty backs indentations over 1 inch, which compares well against the AS3's 20-year coverage for indentations over 1.5 inches.
The main trade-off is price. At $1,795 for a queen, it costs roughly $750 more than the AS3. That premium buys better edge support, a denser construction, and white-glove delivery, but for most people under 200 lb the AS3 still delivers better pressure-relief numbers in our testing.
How to choose a memory foam mattress
Firmness is the first decision. Side sleepers need a medium (4 to 6 out of 10) to avoid shoulder and hip pressure points. Back sleepers can go medium to medium-firm (5 to 7) to keep the spine in line. Stomach sleepers should avoid anything softer than a 6, since a soft foam lets the hips sink and compresses the lower spine.
Cooling is worth scrutinizing on memory foam. Traditional petroleum-based foam traps heat because its closed-cell structure does not let air move. Open-cell foams like Bio-Pur and gel-infused foams like the Saatva's comfort layer mitigate this, but neither will sleep as cool as a latex hybrid or a coil bed. If you run very hot, the Avocado Green is the honest top pick despite being a latex hybrid.
Motion isolation is where memory foam beats every other category. All four all-foam picks here scored 8.8 or higher in our wine-glass test. If you share a bed with a light sleeper, this is the most measurable advantage of memory foam over coil or latex.
Edge support is the category weakness. All-foam beds compress at the perimeter more than hybrids. For a king-sized couple using the full sleeping surface, that matters less. For someone who sits on the bed edge daily, reinforced coils make a real difference.
Common questions
Is memory foam good for back pain?
Memory foam can help with back pain, but only if the firmness matches your sleep position. A side sleeper on a firm foam will have worse hip and shoulder pain. A stomach sleeper on a soft foam will have worse lower-back compression. The Sleep Foundation's 2024 mattress guidance recommends medium-firm for most back-pain sufferers, which aligns with the AS3 (5/10) or the Loom and Leaf Firm (7/10) depending on your weight and position.
How long does memory foam last?
A high-density memory foam mattress (4 lb per cubic foot or higher) typically lasts 8 to 10 years before sagging past the 1.5-inch threshold most warranty policies use as a benchmark. The Saatva Loom and Leaf uses 5 lb foam, which puts it at the high end for durability. The AS3 uses a high-density Bio-Core base, which Amerisleep covers against sagging over 1.5 inches for the full 20-year warranty period.
Does memory foam off-gas?
All new foam mattresses off-gas volatile organic compounds when first unpacked. The smell typically dissipates within 24 to 72 hours in a ventilated room. In our testing, the AS3's plant-based foam cleared in 72 hours and the Puffy Original took slightly longer at around 96 hours. All CertiPUR-US certified foams in this list meet low-emission limits regardless of initial smell.
What is the difference between memory foam and latex?
Memory foam is slow-responding. It contours and holds your shape, which maximizes pressure relief and motion isolation. Latex is fast-responding. It pushes back immediately, sleeps cooler, and has more bounce. Neither is universally better. Side sleepers and couples generally favor memory foam. Active sleepers and hot sleepers generally prefer latex or a latex hybrid like the Avocado Green.
This guide is part of our Best Mattress by Type hub — compare all the top picks and narrow down your choice there.