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Best King Size Mattresses of 2021

Investing in a king size mattress is a big decision. This guide will help you be well-informed when you decide which is the best mattress for you!

By Tyler Moyer

A king-size mattress is a perfect solution for couples looking for ample space to get a good night’s sleep. They are spacious, kid- and pet-friendly, and widely available from most mattress brands. King size mattresses have certain advantages, namely the extra space. Of course with a larger mattress comes a larger price tag.

Thankfully, the emergence of online-only mattress brands have made King size mattresses available at lower prices. If you’ve already made the decision to invest in a king-size bed, the next question is obvious; What is the best king size mattress, and which one should you buy? In this review, we’re sharing our top 10 picks for king size mattresses so you can feel confident in your purchase. You’ll also find a shoppers’ guide for purchasing a king-size mattress, including what to look for, the size’s pros and cons, who they’re best for, and the different types available online.

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Top 10 Best King Size Mattresses of 2021

Nectar – Editor’s Pick

Nectar

Editor's Pick

Made from high-density foam, the Nectar is designed for long-term support and conformity. It’s a mid-level firm mattress that has great motion isolation, comfort, and much more at a more affordable price than similar quality beds in the market.

Score
4.7 / 5.0
Firmness

6

Trial period

365

Reason to buy

Best Bed-in-a-box on a budget

Young newlyweds who want to upgrade to a king-size mattress can often experience sticker shock at the price tag. The Nectar offers a budget-friendly option for singles, recent grads, and couples who want the experience of a king bed without draining their savings accounts.

Speaking of couples, our brilliant editor and sleep science coach has something to say about how well this king mattress performs for two: “This bed isolates motions super well, so if you or your partner is a light sleeper, your movements and midnight bathroom runs shouldn’t wake each other up.” That means plenty of space and peaceful sleep at a reasonable price. You can watch Loren’s full review of our editor’s pick, the Nectar king size mattress, below.

Read our full Nectar Mattress Review to learn more!

Editor’s Pick for Best King Size Mattress: Nectar Review

Saatva Classic – Best King Mattress for Combination Sleepers

Saatva Classic

Best for Combination Sleepers

The Saatva marries the look and the feel of a traditional innerspring mattress with new technology for a final product that’s both supportive and comfortable.

Saatva Classic Mattress
Score
4.7 / 5.0
Firmness

Offered at plush, luxury firm and firm

Trial period

180 nights

Reason to buy

High quality and custom firmness options

The Saatva mattress contains a low-gauge Bonnell coil support core that’s topped with a plush comfort system and a euro-top cushioning layer, which together provide more added comfort than you’ll find in most innerspring options.

Bonnell coils help keep the mattress relatively affordable, and they also keep it supportive. These coils can withstand high levels of compression without shifting. As such, the Saatva takes from the best of both worlds: it has the support, response, and durability of an innerspring mattress and the conforming pressure relief of CertiPUR-US foam or hybrid model. Getting it in a King size just maximizes the surface area of this luxury, and we think you will want as much as you can get!

Read our full Saatva Mattress Review to learn more! 

Helix Midnight – Best King Bed for Pressure Relief

Helix Midnight

Best for Pressure Relief

The Midnight is Helix’s best seller, which is no surprise to us. The king-size version just gives you more to love!

helix midnight mattress
Score
4.8 / 5.0
Firmness

6

Trial period

100 nights

Reason to buy

Made for side sleepers

If you’re looking for a mattress that helps relieve pressure along sensitive parts of the body, the Helix Midnight might just fit the bill: and at a reasonable price, too. As the best-selling mattress in the Helix line, the Helix Midnight is a medium-firm mattress that’s great for lightweight and average-weight side sleepers who want extra pressure relief and weight distribution.

A robust layer of individually wrapped coils makes up the support section of the mattress, balancing the body’s sensitive joints atop the layer and helping sleepers feel comforted without allowing for too much sinkage. The comfort layers of the mattress are made from Helix’s Memory Plus foam and responsive polyfoam, which work in tandem to help relieve pressure buildup.

Whether you purchase the Helix Midnight in a small Twin size or a broad, sprawling King, the bed offers a high-quality construction at a great value.

See our full Helix Midnight Mattress Review to learn more.

WinkBed – Best King Size Bed in a Box

WinkBed

Best Bed in a Box
WinkBeds is a family-owned operation that focuses on details to attract customers to their luxury mattresses, which are made to order in Wisconsin. The company believes so strongly in their mattress quality, that they attach a lifetime warranty to them.
The WinkBeds Original
Score
4.3 / 5.0
Firmness

Varies

Trial period

120 nights

Reason to buy

Four firmness options

The Winkbed mattress is our top pick for the best king size bed in a box. It measures a mighty 14” from base to cover and contains a gel-infused cooling layer along with pocket coils.

The Winkbed features a hybrid construction that has more of a traditional innerspring mattress feel, while still providing a good amount of cushion throughout its memory foam layers for pressure relief.

In addition, if you’re someone who tends to sleep hot, then the Winkbed could be an excellent choice. It’s breathable comfort layers and pocketed coil design allow for sufficient airflow that will keep you cool throughout the night. Overall, it’s a solid choice when it comes to bed-in-a-box mattresses.

See our full Winkbed Review to learn more! 

Casper Original – Best Memory Foam King Mattress

Casper Original

Best Memory Foam
The original mattress that made the brand famous, the Casper is known for its design that suits all sleep positions. Casper's Zoned Support feature is engineered to support the hips, shoulders and back to keep the spine aligned. At an affordable price point, too, this mattress is hard to beat.
Casper Original Mattress
Score
4.8 / 5.0
Firmness

6

Trial period

100 nights

Reason to buy

Affordable mattress made for all sleepers

The Casper Original mattress is an excellent option for memory foam lovers looking to upgrade to a king mattress. It is engineered to accommodate all sleeping positions and has zoned support so the entire body will be supported differently. The Casper is the original mattress in a box, and even though there have been dozen to follow suit, it is still one of our favorites.

Even though it is a memory foam mattress, it has recently been upgraded with cooling features so sleepers do not overheat at night. I will say, it is better for lightweight and average weight sleepers. If you are over 250 pounds, you may sleep better on the Casper Wave mattress. Coming in right around a 6/10 on the firmness scale, it is the perfect medium-firm that will not cause hips and shoulders to jam, but will keep the spine aligned and hips from sinking too much.

See our full Casper Mattress Review to learn more. 

Birch Living – Best Cooling King Mattress

Birch

Best Cooling King Mattress
The Birch mattress is made for those who want a premium, all-natural bed with an affordable price tag. A medium-firm hybrid mattress, the Birch uses Organic cotton, wool and natural latex to create a sleep surface for eco-conscious consumers.
birch mattress
Score
4.9 / 5.0
Firmness

6.5

Trial period

100 nights

Reason to buy

Affordable, all natural hybrid

The Birch mattress is a great fit for earth-loving couples or simply a King size aficionado searching for an eco-friendly mattress. The Birch is an organic mattress that doesn’t contain harmful chemicals or synthetics: perfect for parents with children who climb on top of their bed often.

Made by Helix Sleep,—a brand that manufactures mattress models like the Helix Midnight and Helix Sunset—the Birch mattress is an organic option that comes in a medium-firm firmness setting. That firmness level is great for back sleepers and some lightweight stomach sleepers.

Leesa – Best King Mattress for Aches and Pains

Leesa

Best King Mattress for Aches and Pains
The Leesa mattress adapts to all sleep positions and most body types. With its cooling foam and additional layers that both hug and support you, it's no wonder customers love sleeping on their Leesa.
leesa hero image
Score
4.9 / 5.0
Firmness

6

Trial period

100 days

Reason to buy

Great for most everyone! Excellent all-around mattress.

If you are looking to get a lot of bang for your buck in your new king mattress, the Leesa original is hard to beat. Most people upgrade to a king-size mattress when they are moving in with a partner, or have been living with a partner for a while and are simply in need of more space.

Leesa is a great choice for couples! The edge support when you sit down to tie your shoes may not seem like it is the best in the world, but it holds shape when you use the entire surface really nicely. The foam isolates motion well and allows each person to find their preferred position at night without the other person feeling every single movement. you may feel a tiny shake when your partner moves around, but it shouldn’t be too disturbing!  Speaking of couples and motion isolation, Leesa also made our list of the best mattresses for sex!

See our full Leesa mattress review to learn more. 

GhostBed Luxe – Best King Mattress for Hot Sleepers

GhostBed Luxe

Best for Hot Sleepers
Considered one of the best cooling memory foam mattresses on the market, the GhostBed Luxe is a great option for sleepers who love the feel of memory foam but tend to sleep hot.
ghostbed lux hero image
Score
4.7 / 5.0
Firmness

5.5

Trial period

101 nights

Reason to buy

Top-of-the-line cooling technology

All mattress models in the GhostBed line have their fair share of advanced cooling measures, but the GhostBed Luxe is one of the best cooling mattresses we’ve seen. All too often, hot sleepers have to resort to ultra-firm beds so that they don’t feel “trapped” in a mattress and thus feel hotter. But the GhostBed Luxe combines a soft feel and intentional temperature control to help hot sleepers spend less time sweating and more time sleeping. The cover feels cool to the touch, the breathable coils offer great airflow, and the bed uses gel memory foam to help mitigate the heat-trapping tendency of foam.

Because the GhostBed Luxe comes in at a 5 out of 10 on our firmness scale, it’s good for side sleepers and some back sleepers (predominantly those who are average-weight and lightweight). Stomach sleepers might want to choose a firmer mattress for a bit more support, but couples will appreciate the stellar motion isolation the GhostBed Luxe is able to offer. While it’s a bit more expensive than other mattresses that GhostBed offers, we think this mattress is worth it if you’re tired of waking up hot.

See our full GhostBed Luxe Mattress Review to learn more.

DreamCloud Premier – Best Pillow Top King Mattress

DreamCloud Premier

Best Pillow Top King Mattress
This luxury hybrid mattress comes with cradling technology and plush comfort that most sleepers love. If you're looking for a cushy yet supportive mattress with all the right features, the DreamCloud Premier could be the mattress for you.
Score
4.8 / 5.0
Firmness

6

Trial period

365 days

Reason to buy

A luxury mattress with a great return policy

With one look at the DreamCloud Premier mattress, it’s evident that the bed is built for a King: pun intended! From the luxurious gold coloring of the cover to the robust 15” height, the bed gives off an air of durability and prestige. Topping off the look of this mattress is the brand’s TrueLoft Euro Top pillow top, which combines memory foam and fabric for a cushioning feel on top of the mattress. The tufted pillow top will help shoppers achieve that ever-so-popular “hotel bed” feel.

Back and side sleepers should feel especially comfortable on the DreamCloud Premier mattress because of its medium-firm feel. While some stomach sleepers might not find the bed to be firm enough for their liking, those who tend to sleep hot should appreciate the bed’s thick layer of breathable coils. The Edge Shield Coil System will allow air to move freely from one side of the mattress to the other: even in a robust King size.

See our full DreamCloud Premier Mattress Review to learn more.

Brooklyn Bedding Aurora – Best For Side Sleepers

Brooklyn Bedding Aurora

Best for Side Sleepers
The Aurora hybrid is Brooklyn Bedding's most popular mattress. It comes in three firmness levels and features both innerspring coils and cooling copper-infused gel foam, meaning it suits those who sleep hot, as well as a wide range of sleep preferences.
Brooklyn Bedding Aurora Mattress
Score
4.8 / 5.0
Firmness

5

Trial period

120 days

Reason to buy

Cooling features and overall comfort

Side sleepers, rejoice! The Brooklyn Bedding Aurora mattress is a cooling mattress that’s just as easy on your joints as it is on your body temperature. Though it comes in three distinct firmness levels, we recommend that most side sleepers choose the soft version of the Aurora. Coming in at 5 out of 10 on our firmness scale, the soft Aurora will cradle sensitive joints like the hips and shoulders while helping to ensure proper spinal alignment.

Another factor we love about the Aurora? The responsiveness and durability of this mattress. Because it’s made with steel coils, we think the Aurora will hold up nicely for years. In our mattress lab, we also found it relatively easy to move around upon and change positions.

King Size Mattress Buying Guide

Here’s an overview of purchasing considerations and factors when buying a king size mattress:

  • Sleeping position—Different positions have different support requirements, so the best king mattress will depend on whether you’re a side, back, stomach, or combination sleeper. The best mattresses for back and stomach sleepers are usually firmer, while conforming mattresses tend to be the best beds for side sleepers.
  • Weight—Heavier sleepers not only tend to sleep hotter, but they experience more sinkage, meaning that a medium-firm mattress may feel soft to an overweight or tall individual. Similarly, lightweight or petite individuals who desire firm beds may find their match in mattresses that feel soft to most sleepers.
  • Temperature—Do you sleep cool or hot? All-foam mattresses tend to sleep hotter, although recent advancements have improved airflow and made mattresses more breathable. If temperature regulation is important, consider a hybrid or innerspring king size mattress or an all-foam variety with dedicated cooling properties. Check out our best cooling mattresses article for more information.
  • Material—The bulk of mattresses on the market are innerspring, foam, latex, or hybrid styles. Each material has its own benefits and drawbacks, and they vary in cost, durability, and more. 
  • Firmness—While there’s no standardized firmness scale across the industry, mattresses range from 1 to 10 in firmness, with 1 being extra soft and 10 being extra firm. Your weight and sleeping position will most impact the firmness that feels best to you and supports proper spinal alignment. Our mattress firmness guide is a great resource if you’d like to learn more.
  • Thickness—Most mattresses measure 10 inches in thickness, but luxury and thick options can measure 15 inches or more. 
  • Price—Mattresses vary dramatically in price based on the quality of materials used, the make, the manufacturer, and other costs, like delivery fees. Budget mattresses can cost just a couple hundred dollars, whereas luxury king size mattresses can cost $2,000 or more. 
  • Performance factors—Consideration of a king-size mattress’ performance will give you a well-rounded perspective on the product’s pros and cons. Consider properties like durability (how long it will last), motion isolation, conformity, temperature neutrality, off-gassing, edge support, noise, and more.
  • Policies—Third-party retailer and mattress company policies like shipping, warranties, returns, and trials can greatly impact customer satisfaction and experience, especially if you’ll be shopping for your king size mattress online. Make sure you’re comfortable with the level of protection for the investment you’re making and with the trial and return policies, just in case you’re not happy with your purchase. Also be aware that failing to use proper foundation, box spring, or bed frame can also void your warranty. 
  • Mattress weight—By nature of their size, king mattresses tend to be heavier and bulkier.
  • Durability—Durability is key for king size mattresses, which often support the weight of two individuals night in and night out. Research and read reviews about the mattress’ longevity, looking for answers to questions like, “Does it sag over time?” and “How’s the edge support?”

King vs. Queen Mattress

If you’re shopping for a king size mattress, you’ve probably also weighed the option of buying a queen instead. Queen mattresses are more affordable, and if you’re a single person with an average body type they likely provide enough space for you to be comfortable. That said, there are plenty of reasons why a king might be the right choice for you.

Most importantly, you’ll have more room on a king. A standard king mattress measure 76” x 80”, 16” wider than the queen’s 60” x 80” measurements. Whether it’s just you, you and a partner, or you and a pet, this extra space will come in handy if you like to spread out, move around a lot, or even get some space between you and your partner.

A queen does have it benefits, though. As I mentioned above, they are more affordable. They’re also lighter and therefore easier to move around, flip, or rotate. If you want your next mattress to be something that you spend many, many years on, then a king might be worth it for you. If this is more of a transition mattress, consider a queen.

For a more comprehensive breakdown of the great king vs. queen debate, take a look at our article on king vs. queen size mattresses, or head over to our wonderful mattress size guide.

Related: Best Queen Size Mattresses

Types of King Size Mattresses 

A bigger mattress can solve issues of disturbances like snoring, turning, tossing, and cover-stealing from a partner. If you’ve decided that a king bed is what you need, you’ll need to decide on the exact type of mattress you’re after. Here are the details and dimensions of the most common king size mattresses.

King

One size larger than a queen, a traditionally sized king provides sleepers with an additional 16 inches of width. A standard king measures 76 by 80 inches, which is the same as two twin XL mattresses pushed together. 

Eastern King

An eastern king is simply a synonym for a standard king, and it also measures 76 inches wide by 80 inches long.

California King

The only difference between a California king and a standard/eastern king is in the width and length. California kings measure 84 inches long by 72 inches wide, so they’re best for especially tall individuals and those who enjoy extra space.

Split King

A split king, otherwise known as a dual king mattress, comes in two pieces rather than one. Each piece is roughly the same size as a twin mattress. Creating a king bed out of two separate mattresses allows each partner to have their own space, which is often customized for firmness level or adjustable, while still sharing closeness with their partner.

Pros & Cons of King Mattresses

PROS

  • More space
  • Less tossing and turning
  • Proper sleeping positions
  • Kid- and dog-friendly

CONS

  • Bulkier
  • Can be heavy and hard to move
  • More expensive

Who Is a King Mattress Best For?

Individuals and couples considering a king are most often deciding if a king is worth the extra money, or if a queen would suffice. Understanding the core differences between them will help you make an informed choice. 

Most queen mattresses measure 60” x 80”, whereas a king mattress typically measures 76” x 80”. A queen requires a room, at a minimum, that measures 10’x12’, and a king requires a room that measures at least 10’x14’, not accounting for other bedroom furniture. In general, queens work well for single sleepers and for couples who don’t need much sleeping space. Kings are typically preferred for couples who want the maximum amount of personal sleeping space.

If the price is a concern, keep in mind that while a king does generally cost more than a queen, affordable options are available. Both a king and a queen are widely available in a variety of styles at many price points, so you can find a quality mattress in both sizes at a price point that works for you. 

As mentioned, room size becomes a major factor when couples realize that a king is more than a foot wider. Leaving two feet of space on three sides of your room is recommended by interior designers, but that’s the minimum. If you want to include a wardrobe, nightstands, and other pieces, you’ll need more room. 

At the end of the day, the choice between a king or a queen mattress is a matter of personal preference. If you sleep alone, queen size is a great choice and will save you room space. If you’ve been sleeping with a partner for several years in a queen and find that your sleep is compromised for whatever reason, upgrading to a king might pave a path to more restful sleep and better overall wellness for the two of you.

Mattress Materials 

With all of that in mind, you’ve probably decided whether or not to pull the trigger on a king size mattress. Congratulations! But don’t power down just yet. There are still many qualities, such as preferred materials, that you need to explore before deciding which king to purchase. To help you with that, we’ve put together small, informative blurbs on the pros and cons of the four main mattress materials: memory foam, innerspring, latex, and hybrid.

Memory Foam

Have you ever slept on a cloud? Probably not. But you can come pretty darn close to replicating the (imagined) experience with memory foam. Memory foam’s contouring ability is generally unmatched in the mattress world. The layers of foam react to your body and cradle all of the sensitive pressure points, like hips and shoulders.

While comfortable, foam beds can have some qualities that may turn you off. The very traits that make it so good at contouring also make it sleep warmer than the other mattress types. Those soft, dense foam layers can very easily trap heat. And that’s not the only thing they can trap; while some may feel comforted by the contouring foam some may feel enveloped by it. 

Still, many mattress companies are combating this problem of overheating with things like cooling gel foam, and if you feel that you’re sinking too deep into the foam, that’s nothing a firm mattress topper won’t solve. If you want to learn more, head on over to our best memory foam mattress guide.

Innerspring

Innerspring mattresses have two big things going for them: breathability and responsiveness. Constructed without thick layers of foam or latex, these beds have excellent air flow. Responsiveness refers to how easy a bed is to move around on, and if you’ve ever bounced around on a steel coil bed, then you know how springy they can be.

You won’t find memory-foam-levels of contouring in innerspring mattresses, though. In fact, they tend to be on the firmer side, since they lack the comfort foam layers that you find in hybrid beds. They can also make quite a bit of noise as they age, if that is a concern of yours.

If those drawbacks turned you off from innerspring, there’s one last thing you should keep in mind: they tend to be the most affordable mattresses on the market. If that intrigues you, check out our best innerspring mattress list.

Latex

Latex mattresses offer comfort, support, and peace of mind. What do we mean by that? Well, many latex mattresses are manufactured with the environment in mind. The best way to tell whether or not a mattress brand uses sustainable processes and materials is to take a look at their certifications. The Global Organic Latex Standard (GOLS) and OEKO-TEX Standard 100 are good indicators of a product that is earth-friendly.

For a more in-depth look at what makes a mattress sustainable or organic, take a look at our best latex mattress and best organic mattress articles.

Hybrid

At last, we arrive at hybrids. These mattresses are very interesting, because they combine elements from the three mattress types that we’ve already covered. Built with a support layer of springs and top layers of either memory or latex foam, the best hybrid mattresses offer the breathability and responsiveness of innerspring, along with the comfort and pressure relief of memory foam or latex. If this sounds like the mattress for you, be warned that they can be quite pricey.

Conclusion

If you’re on the hunt for a king-size mattress, you’re already well on your way to more comfort and better sleep. Most owners of king size mattresses would tell you that the extra expense is worth it. With extra space, you’re less likely to feel your partner’s movements throughout the night, and bedroom space, especially a master, simply looks better in a larger bedroom. Investing in a king mattress is an important step toward guaranteeing restful sleep, so we hope you’ll use this guide to the best king mattresses to get you there.

If you still need guidance in your mattress buying journey, check out our ultimate mattress buying guide.

Recap of the Top Rated King Size Mattresses

Mattress Award Nerd Score
Saatva Best for Combination Sleepers 4.7/5
Nectar Editor’s Pick 4.9/5
Helix Midnight Best For Pressure Relief 4.8/5
Winkbeds Best Bed in a Box King Mattress 4.5/5
Casper Best King Size Memory Foam Mattress 4.8/5
Birch  Best Cooling King Mattress 4.8/5
Leesa Best King Mattress for Aches and Pains 4.8/5
GhostBed Luxe Best for Hot Sleepers 4.7/5
DreamCloud Premier Best Pillow Top King Mattress 4.8/5
Brooklyn Aurora Best for Side Sleepers 4.5