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King size memory foam mattresses starting at
$1149
Available in 5 models
Why Choose a King Size Memory Foam Mattress?
Memory foam is known for its unrivaled pressure relief and a cloud-like feel. It conforms to your body's unique shape, cradling your curves and distributing weight evenly to minimize pressure points. Amerisleep's proprietary Bio-Pur® takes those qualities a step further by being more responsive and breathable than traditional memory foam. In a King size, this benefit is amplified, offering an expansive surface area for unparalleled comfort and relaxation, perfect for couples who want extra space.
Our King size memory foam mattresses are designed to provide:
- Unparalleled Spaciousness: Enjoy the freedom to move and change positions without feeling confined.
- Exceptional Pressure Relief: Soothe your joints and muscles with foam that adapts to your body.
- Superior Spinal Alignment: Promote a healthy sleep posture and reduce back pain.
- Minimal Motion Transfer: Enjoy undisturbed sleep, even with a restless partner.
- Cooler Sleep: Our open-cell, plant-based Bio-Pur® foam helps you sleep cooler than traditional memory foam.
- Ideal for Couples: The expansive King size provides ample space for two people to sleep comfortably without disturbing each other.
If you're looking for the ultimate in sleep luxury and want a mattress that makes a statement in your master bedroom, our King size memory foam collection is the perfect solution.
Customer Testimonial: "I always thought memory foam was too hot until I found Amerisleep. Their foam is breathable and super supportive.” — Christina Serrano (@chrissymarieblog)
Browse our King size memory foam mattresses starting at $1149.
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Firm King Size Memory Foam
$1649
$1149
with promo
Save
$500
- King: 76" x 80"
- Firm feel
- 2" of Bio-Pur®
- 8" of Bio-Core®
Supportive King Size Memory Foam
$1849
$1349
with promo
Save
$500
- King: 76" x 80"
- Medium-firm feel
- 2" of Bio-Pur®
- 3" of HIVE®
- 7" of Bio-Core®
- Chiropractor Recommended: for spinal alignment and back pain relief
Best-Selling King Size Memory Foam
$2049
$1549
with promo
Save
$500
- King: 76" x 80"
- Medium feel
- 3" of Bio-Pur®
- 2" of HIVE®
- 7" of Bio-Core®
Plush King Size Memory Foam
$2049
$1549
with promo
Save
$500
- King: 76" x 80"
- Plush feel
- 4" of Bio-Pur®
- 1" of HIVE®
- 7" of Bio-Core®
- Softness without sinkage
Softest King Size Memory Foam
$2649
$2149
with promo
Save
$500
- King: 76" x 80"
- Ultra-plush feel
- 3" of Bio-Pur®
- 2" of Active Flex
- 2" of HIVE®
- 7" of Bio-Core®
Best adjustable bed and mattress in a box combo
$4049
$2829
with promo
Save
$1220
- Adjust angles effortlessly
- Zero-gravity position
- Pair our frame with the mattress of your choice
- Made in USA
![Reviews - Average of 4.7 stars]()
15,000+ Reviews
Average of 4.7 stars1![Men's health - Sleep awards winner]()
Sleep Awards
Winner![Business insider - Best mattress for back pain]()
Best Mattress
for Back Pain![Allure - Best mattress to buy online]()
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Online![Forbes - Masterpieces of midnight melatonin replenishment]()
Masterpieces of Midnight Melatonin Replenishment
Why Memory Foam? The Benefits Explained
Memory foam's greatest strength lies in its ability to conform to your unique shape. This adaptive quality cradles your body, easing tension and distributing weight evenly, particularly around sensitive areas like your shoulders, hips, and back. This targeted pressure relief is a key reason why so many people find memory foam mattresses incredibly comfortable. In a King size, this benefit is amplified, offering an expansive surface area for unparalleled comfort and relaxation.
Low Motion Transfer: If you share your bed with a partner, you'll appreciate memory foam's ability to isolate motion. Unlike traditional innerspring mattresses, memory foam absorbs movement, preventing it from rippling across the bed. This means you're less likely to be disturbed when your partner tosses and turns, gets up in the night, or has a different sleep schedule. This is especially beneficial in a King size, where each person has ample space to move without disturbing the other.
What Makes Our Memory Foam Different
- Promotes Deeper sleep: Our breathable materials create a cooler surface so you can fall asleep faster and stay asleep longer.
- Delivers Targeted Support: HIVE® technology and pocketed coils offer dynamic support, healthy spinal alignment, and unique pressure relief.
- Provides Responsive Comfort: Bio-Pur® is more responsive and breathable than traditional memory foam so it contours and cools.
Ready for a great night's sleep?
Shop King Memory Foam MattressesIs a King Size Memory Foam Mattress Right for You?
Our King Size Memory Foam Collection is ideal for:
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Couples
Who prioritize personal space and minimal sleep disturbance. A King size offers ample room for both partners to sleep comfortably in any position.
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Restless Sleepers
Who toss and turn frequently. The expansive surface area of a King size allows for movement without disturbing a partner or feeling confined.
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Families
Who co-sleep with children or pets. A King size provides enough space for everyone to rest comfortably.
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Side & Combo Sleepers
Who benefit from the exceptional pressure relief and contouring of memory foam. The King size offers plenty of room to change positions throughout the night.
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Back Pain Sufferers
Those seeking a mattress that can properly align the spine and alleviate pressure points. The supportive nature of memory foam, combined with the King size's generous surface area, is excellent for back pain relief.
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Those with Joint Issues
Individuals looking for a mattress that offers gentle, conforming support to ease joint pain. A King size memory foam mattress provides a comfortable and supportive sleep surface with ample room to adjust positions.
A King size memory foam mattress offers the ultimate in luxurious space and comfort for a truly restorative sleep experience.
How Much Do King Size Memory Foam Mattresses Cost?
Quality memory foam beds can range from $800–$2500+, depending on factors like:
- Foam Density & Thickness: Thicker comfort layers and higher foam density often cost more but offer superior pressure relief and durability.
- Cooling Features: Advanced cooling technologies like plant-based foam, open-cell designs, and special covers can add to the cost.
- Zoned Support: Features like HIVE® technology, which provide targeted support, contribute to both cost and comfort.
- Warranty & Durability: Longer warranties often indicate higher-grade materials and construction, which can influence the price.
Amerisleep King size memory foam mattresses start at about $1149 with promotions—delivering top-tier comfort, eco-friendly construction, and robust warranties.
King Memory Foam Mattress Comparison Chart
| Feature | AS1 | AS2 | AS3 | AS4 | AS5 |
|---|---|---|---|---|---|
| Firmness | Firm | Medium-Firm | Medium | Plush | Ultra-Plush |
| Feel | Solid, Sturdy | Supportive with a touch of give | Balanced comfort and support | Soft, Cloud-Like | Our Softest, Most Luxurious |
| Profile | 10" | 12" | 12" | 12" | 14" |
| Ideal For | Stomach Sleepers | Back Sleepers, Heavier Individuals | All Sleepers | Side Sleepers | Side Sleepers, Joint Pain |
| Support | 8" Bio-Core® Base | 7" Bio-Core® Base | 7" Bio-Core® Base | 7" Bio-Core® Base | 7" Bio-Core® Base |
| Cooling | Bio-Pur® foam | Bio-Pur® foam | Bio-Pur® foam | Bio-Pur® foam | Bio-Pur® foam |
| Motion Isolation | Good | Good | Excellent | Excellent | Excellent |
| Edge Support | Good | Good | Excellent | Good | Good |
| Price (King) | $1149 | $1349 | $1549 | $1549 | $2149 |
| Shop Now | Shop the AS1 | Shop the AS2 | Shop the AS3 | Shop the AS4 | Shop the AS5 |
AS3: Our Best-Selling Memory Foam Mattress
The AS3 strikes the perfect balance of comfort and support, making it our most popular memory foam mattress. Its medium feel suits a wide range of sleepers. With 3 inches of our Bio-Pur® foam and zoned HIVE® technology, you get:
- Pressure relief that adapts as you change positions
- Enhanced airflow for cooler sleep
- Targeted support for optimal spinal alignment
- Minimal motion transfer, even with a partner
"The AS3 feels like sleeping on a cloud, but I’m never overheated. Perfect combo!” — Christina Serrano (@chrissymarieblog)
Choosing the Right Memory Foam Mattress
Watch as Dr. Jordan Burns, a practicing chiropractor, shares his expert tips on choosing a memory foam mattress for optimal comfort and support:
Key takeaways from Dr. Burns:
- Choosing the right mattress firmness is crucial for spinal alignment. Learn more about mattress firmness.
- Proper pillow support is essential for neck pain relief. Learn how to choose the right pillow for neck pain.
- Sleeping position can significantly impact back pain. Learn about the best sleeping positions for lower back pain .
Choosing the Right Size: Is a King Mattress Right for You?
Our King size mattresses offer an expansive sleep surface, measuring 76 inches wide by 80 inches long. They are the perfect choice for couples who desire maximum personal space or for those who simply enjoy the luxury of stretching out. To determine if a King size is right for your bedroom, consider the size of your room and your personal sleep preferences. A King size bed typically requires a larger master bedroom. For a detailed comparison of all mattress sizes, including dimensions and recommendations, visit our comprehensive Mattress Size and Dimensions Guide
Frequently Asked Questions
Are memory foam mattresses hot to sleep on?
Traditional memory foam can trap heat, but Amerisleep’s Bio-Pur® foam is open-cell and more breathable, reducing heat retention.
How long do memory foam mattresses last?
High-quality foam like ours often lasts 8–10+ years, thanks to robust density and supportive base layers. We back our mattresses with a 20-year warranty.
Which memory foam firmness is right for me?
It depends on your sleep position. Side sleepers often like medium to plush (AS3, AS4, AS5). Back sleepers may prefer medium-firm (AS2). Stomach sleepers might opt for AS1. Take our mattress quiz to find your perfect match!
Do memory foam mattresses smell (off-gassing)?
Our foams are low VOC and CertiPUR-US® certified. Any “new mattress smell” typically dissipates within days, if at all.
Can I use a regular box spring with a memory foam mattress?
A solid foundation or slatted base is usually recommended. A worn or old box spring might cause sagging. Learn more about whether a bad box spring can ruin a mattress.
How does memory foam help with back pain?
It cradles the spine, relieving pressure in the lumbar area, promoting better alignment—especially with zoned support (HIVE®).
Do I need a mattress protector?
While not mandatory, a protector helps keep the mattress clean and prolongs its lifespan.
Are your memory foam mattresses adjustable-base friendly?
Yes. All our foam models bend easily with adjustable bases—no damage, no compromise on support.
What should I do with my old mattress?
Many charities accept mattress donations. You can also check with your local waste management company for recycling options. We also offer old mattress removal services in select locations. Learn more about mattress donation options.
Do you have any showrooms where I can try out the mattresses?
Yes, we have a showroom located in Scottsdale, Arizona at the Optima Camelview. We encourage you to visit us and experience the comfort of our mattresses in person. Our knowledgeable sleep experts can answer any questions you have and help you find the perfect mattress for your needs.
What size sheets do I need for a King mattress?
You will need King size sheets for a King mattress. King sheets typically measure 78 inches wide by 80 inches long.
Is a King mattress big enough for two people?
Yes, a King mattress is the largest standard size and provides ample space for two people to sleep comfortably, even if they are restless sleepers or have different sleep preferences.
How much does a King size memory foam mattress weigh?
The weight of a King size memory foam mattress can vary depending on the specific model and materials used. On average, a King size memory foam mattress from Amerisleep weighs between 90 and 140 pounds.
What is the difference between a King and a California King?
A standard King size mattress is wider than a California King, while a California King is longer. A King measures 76 inches wide by 80 inches long, and a California King measures 72 inches wide by 84 inches long. See our Mattress Size and Dimensions Guide for more details.
Rest Easier on a Premium King Size Memory Foam Mattress
Experience the ultimate in comfort, support, and spaciousness with our King Size Memory Foam Collection. Whether you're a couple seeking ample room or an individual who loves to stretch out, we have a model perfect for you. Discover the difference of plant-based Bio-Pur® foam and say goodbye to restless nights.
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