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May 22, 2024

9 Best Split King Mattresses of 2023, Tested by Experts

We've been independently researching and testing products for over 120 years. If you buy through our links, we may earn a commission. Learn more about our review process. Because you both deserve a

We've been independently researching and testing products for over 120 years. If you buy through our links, we may earn a commission. Learn more about our review process.

Because you both deserve a good night's rest!

Mattress shopping with your partner isn't always the most exciting experience, especially if one of you moves around at night while the other lies in bed unable to fall asleep. While the best mattresses for couples are designed with that in mind, providing a balance of comfort and support along with much-needed motion isolation, you might still feel like choosing one mattress is too much of a compromise. As great as motion isolation is, nothing beats having your own mattress.

If that sounds like you, consider swapping your mattress for a Split King bed, which is two Twin XL mattresses joined together. This way, both you and your partner can have it all and you can still use your own sheets. On top of that, you can even pair it with a matching Split King adjustable bed for ultimate, personalized comfort. Plus, you won't have to worry about finding a position that's comfortable for both of you when watching TV.

What's the best Split King mattress for most people? Our top-tested Split King mattress is the Saatva Classic Mattress. It's great for a wide range of sleepers, has earned high praise from real users and comes with full-service setup at no additional cost. If you prefer a boxed mattress to set up on your own time or are looking to spend under $1,000, we recommend the Allswell Luxe Hybrid.

Remember: Not all mattress brands offer a Split King or Twin XL, since it's not as popular as a standard Queen or King. But at the Good Housekeeping Institute Textiles Lab, we evaluate all types of bedding and mattresses and have rounded up our top-tested mattresses available in Split King or Twin XL sizes.

From reviewing over 10,000 survey responses from everyday mattress owners to working with consumer testers to directly test hundreds of popular styles, our Lab analysts are experts at finding the best mattresses for every type of sleeper. Whether you're looking for a cooling mattress, the best hybrid mattress available, an easy-to-assemble boxed mattress you can easily buy online or even a mattress that's under $500, we've reviewed extensive data on it all to help you find your next bed.

Read on for more about how to choose the best mattress for you and our answers to popular questions about Split King beds.

Best Mattresses | Best Mattresses in a Box | Best Online Mattresses | Best Cheap Mattresses | Best Innerspring Mattresses | Best Memory Foam Mattresses | Best Hybrid Mattresses | Best Hybrid Mattresses in a Box | Best Cheap Mattresses | Best Mattresses Under $500 | Best Organic Mattresses | Best Latex Mattresses | Best Mattresses for Back Pain | Best Mattresses for Side Sleepers | Best Cooling Mattresses | Best Mattresses for Adjustable Beds | Best Soft Mattresses | Best Firm Mattresses

Most mattresses you'll find online come shipped in a box, but Saatva provides classic white glove delivery for its beds at no extra cost. While memory foam and hybrid beds have taken over the market, this mattress from Saatva provides everything you love about a traditional innerspring mattress from the top-notch edge support to the bouncy feel. If you're not sure if it's right for you, the brand offers a generous 365-day sleep trial — just note, you'll have to pay a $99 pickup fee if you decide to return it.

Who it's best for: Shoppers who want the bounce and breathability of a traditional innerspring mattress along with free white glove delivery and mattress removal.

Tester notes: Saatva has consistently earned high praise from our consumer panel, with many highlighting the comfort, support and positive impact on their sleep quality. The Classic Mattress is the brand's most popular style and features high-quality materials and construction plus excellent edge support, which users note has made it easier to get in and out of bed. Plus, the 11.5-inch version is compatible with an adjustable base. On top of that, the brand's customer service is top-notch and has been described as helpful and efficient both before and after the buying process.

READ OUR FULL REVIEW: Saatva Mattress Review: Our Pick for the Best Overall Bed

This affordable mattress is a fraction of the cost of our other picks yet still stands out for its glowing reviews and high ratings from our tester panel who found it undeniably comfortable. It's a hybrid model, which means it combines cushiony memory foam with durable coils for a comfortable yet supportive feel. Its crowd-pleasing medium firmness will appeal to a wide variety of sleepers. And for those who hate waiting around all day for a delivery team: this one arrives compressed in a box, so you can set it up at your convenience.

Who it's best for: Price-conscious shoppers who prefer to spend under $1,000 without sacrificing comfort. In our surveys, younger adults (especially new homeowners or apartment renters in their 20s) gave this mattress higher scores than older individuals, which is expected, as edge support and ease of setup were more important to older users.

Tester notes: In our surveys, users told us this mattress was more than worth the price and gave it great scores in multiple categories. Some even shared that it helped alleviate their back and neck pain and loved how they felt like they were sleeping on top of the hybrid bed instead of sinking into it. The caveat for this one is the edge support. The edges sunk down more than other mattresses we've reviewed, which can be a deal-breaker as it makes getting in and out of bed more difficult. Still, many raved about the high-quality feel, with one comparing it to a "plush hotel mattress."

Note: You'll need to purchase two Twin XL mattresses to achieve a Split King. The pricing listed here reflects the total cost of two Twin XL Allswell mattresses

READ OUR FULL REVIEW: Allswell Mattress Review: The Best Budget Bed You Can Buy

If you experience pain in your shoulders, hips or lower back, finding a mattress that will keep your spine in neutral alignment when sleeping is essential. Luckily, Nolah's mattresses are known for just that — providing a pressure-relieving feel with a medium level of firmness. The brand's Original 10" earned top praise from testers and panelists with joint pain, who swore it made a difference in alleviating their back and hip pain.

Who it's best for: Users with joint pain (e.g., back, hip, neck and shoulder pain) in search of a pressure-relieving bed that won't compromise on long-term comfort.

Tester notes: Several of our testers and panelists who've suffered from joint pain told us this bed made all the difference in easing their pain. One highlighted its comfortable feel, noting that the mattress "offers back support while still cradling pressure points," while another shared that the "foam bounces back to retain its support even when changing positions." Just keep in mind that if you've never slept on an all-foam mattress before, many testers told us it took a while to adjust to. One shared, "Although I was experiencing far less back, shoulder and neck pain from this mattress, it still took a few days for me to get used to."

Hybrid mattresses combine cushiony foam with coils to offer a balance of comfort and support, and this one from Bear is one of the best we've ever tested. It's designed with ergonomics in mind, utilizing zonal support where it matters the most. In fact, the bed features extra cushioning around targeted areas like the hips and back for personalized comfort while promoting spinal alignment. Compared to other models on our list, this one is on the newer side, but it's been more than impressive thus far.

Who it's best for: Side and back sleepers, those suffering from back pain and anyone that has struggled to find a truly comfortable mattress.

Tester notes: The ergonomic, zonal design proves effective, earning top scores for every category from comfort and support to sleep quality. Testers have dubbed it "nothing short of amazing," and praised the top-notch support. One shared, "It feels like my entire body is being supported, regardless of my position." Another tester even finds herself sleeping through her alarms for the first time in years from how comfortable she feels on the bed. Just note that Bear makes some claims about using "eco-friendly materials" and natural minerals that promote recovery that we couldn't verify in our research, but we still stand behind this mattress for its exceptional comfort.

Known for its pressure-relieving foam, Tempur-Pedic's mattresses are truly one-of-a-kind. Several testers and panelists shared that they haven't experienced anything quite as comfortable and contouring. While the brand's mattresses often come at a premium, this model uses the same proprietary foam and is compressed and shipped straight to your door at a lower cost. Plus, the pressure-relieving mattress cradles your hips and shoulders in order to promote a neutral, spinal alignment, making it perfect for side sleepers who experience hip pain.

Who it's best for: Side sleepers looking for just enough pressure relief for their hips and shoulders and those who want the unique feel of Tempur-Pedic's foam at a more affordable price point.

Tester notes: According to panelists, the luxurious feel of the Tempur-Cloud is rave-worthy, with several noting that it lives up to its name. Additionally, this model earned high marks for the overall comfort and support provided with standout motion isolation. In fact, some shared that they couldn't feel their partners move or get up entirely while lying on the bed, making it a great option for couples. The brand also notes that the bed may feel firm when you first lie down, which our testers confirmed, commenting that it quickly molds to properly contour your body for personalized support in a "gentle way."

Available discount: Save 30% off this mattress using the code CLOUD30 at checkout.

READ OUR FULL REVIEW: Tempur-Pedic's Tempur-Cloud Delivers Luxurious Memory Foam to Your Door

Responsible for changing how we shop for mattresses online, Casper is known for pioneering the original "mattress-in-a-box" in 2014. Its popularity hasn't waned either. The brand's original mattress is one of the most popular among our panelists and in the entire bedding industry. The bed comes compressed in a small box for you to set up on your own, which many of our survey respondents prefer to the traditional waiting-by-the-phone delivery method. This specific model is made entirely of foam with layers that feature a zoned design to help promote spinal alignment.

Who it's best for: Shoppers who prefer the cradling comfort of memory foam and are willing to spend a bit more on ergonomic support and don't want to wait around for someone to set up their new mattress.

Tester notes: Casper's mattresses earned high scores in our most recent surveys. Of the more than 130 Casper mattress owners, most owned this specific model and called attention to how easy it was to order and set up in addition to the approachable, not-too-tall and not-too-short 12-inch height. One user highlighted how well the bed "conforms to your body." Another said, "It helps with motion transfer much more than the old innerspring mattress I had." Many of our respondents were also brand loyalists, repurchasing the same bed after years of use or purchasing more for other rooms in their homes.

Note: You'll need to purchase two Twin XL mattresses to achieve a Split King. The pricing listed here reflects the total cost of two Twin XL Casper mattresses

Purple mattresses stand out compared to others on the market for their unique feel. Each style comes with the GelFlex Grid, a unique, grid-shaped elastic top layer that proves both airy and supportive. While this model, the brand's original mattress, doesn't feature any cooling technology, the inherent breathability of the bed is unparalleled. On top of that, the one-of-a-kind material has a squishy texture that feels both supportive and pressure-relieving.

Who it's best for: Hot sleepers and those with night sweats in search of a more breathable mattress, couples looking for a bed with good motion isolation, or people who are tired of the same old mattress feel and want to try something new.

Tester notes: It can be hard to understand exactly what the brand's mattresses feel like if you've never tried one, but one textiles analyst describes it as having "the springy texture of latex with the pressure-relieving and cradling feel of memory foam and the breathability of an innerspring mattress." In summary, it combines several different characteristics from a slew of mattress types. Our panelists and testers echoed this and highlighted how the bed feels noticeably cooler than other mattresses they've slept on. The caveat is that several reviewers reported that the delivery took much longer than they expected.

Proving that you don't need to sacrifice comfort when opting for a more "green" organic mattress, this one uses quality materials and thoughtful construction. Made using resilient and bouncy latex layered over coils, it contours to your body without sinking in like foam. On top of that, it's certified by the Global Organic Latex Standard (GOLS) and the Global Organic Textiles Standard (GOTS), so you know the entire manufacturing process adheres to strict guidelines. The brand also offers a generous year-long sleep trial.

Who it's best for: Eco-conscious consumers that prefer organic materials to memory foam or those who enjoy the springy, floating feel of latex.

Tester notes: This is Avocado's most popular mattress and for good reason. Many users told us that they love sleeping on this model and applauded the bed for its comfort and even body weight distribution. Several even commended it for how well it's lasted over the years, noting no presence of "dips" or indents. One user shared, "I like that it is supportive and I don't wake up in pain as I have with other mattresses." On top of that, our analysts commend the brand's commitment to sustainability and carbon neutrality without compromising on comfort or quality.

Note: You'll need to purchase two Twin XL mattresses to achieve a Split King. The pricing listed here reflects the total cost of two Twin XL Avocado mattresses

Ever buy a mattress and wish it was a tad bit softer or firmer? Sleep Number beds are famous for allowing you to pick your perfect firmness level regardless of your preferred sleep position or your body type. Each mattress uses adjustable air-filled chambers that work to keep you at your selected firmness all night and even automatically adapt if you switch positions. While the brand offers separate controls for each side of the bed, a Split King model stands out for its compatibility with a Split King adjustable bed base, so you and your partner can adjust your position without bothering each other.

Who it's best for: Shoppers who aren't sure what level of firmness they prefer and want the ability to change it as they please and couples who want to pair the mattress with an adjustable base.

Tester notes: In our surveys, Sleep Number owners rave about how controlling the firmness levels of their beds has altered the quality of their sleep. While this certainly comes at a high price point, our panelists swore the upgrade was worth the cost. Plus, the brand's mattresses are backed by the Good Housekeeping Seal so rest assured that this model has been heavily vetted by our Lab experts. One expert who owns this bed said, "I was really impressed with how it learned and reacted to my body. It didn't feel gimmicky, seemed really intelligent and actually worked."

Keep in mind that all Sleep Number mattresses need to be paired with a matching base, ranging from simple bed frames to adjustable bases, including those with optional feet warming.

With a century-long history of evaluating consumer products, the Good Housekeeping Institute Textiles Lab has reviewed its fair share of mattresses, including Split King options. As the online mattress industry has boomed since 2014, our analysts have stayed up-to-date with the latest innovations, constantly testing new styles to see if they're worth the hype. In recent years alone, we've surveyed over 10,000 mattress owners and worked with consumer testers to review hundreds of models firsthand. Additionally, our experts use their categorical knowledge to assess everything from materials and structure to brand reputation.

When it comes to reviewing feedback from our testers and survey panel, each user fills out thorough surveys about their experience. We survey our consumer testers several times, first after a few weeks for initial feedback and then after an extended period of months to years to gauge how the bed has fared over time. For our survey panel of Good Housekeeping readers, we send one questionnaire for in-depth feedback on the mattresses they already own.

All of our surveys address a range of aspects, including:

✔️ Ordering and delivery: We ask users to rate and comment on the ease of ordering, how quickly the mattress arrived and whether there were any issues throughout these steps.

✔️ Set up: Whether it's DIY or white glove delivery, users rate how easy the process was and whether the mattress took shape quickly.

✔️ Firmness level: Often, the firmness reported by the brand doesn't match the personal experience of many users. This is why we ask users to rate the firmness of their beds, which helps us understand how soft or firm the mattress feels in real life.

✔️ Edge support: Users share whether the bed sinks when they sit on the edges or if it holds the shape well under weight.

✔️ Comfort and support: Reviewers weigh in on whether they liked sleeping on the mattress immediately and again later in the review period. They also provide comfort and support ratings as well as detailed comments.

✔️ Temperature: We ask whether respondents stayed at a comfortable body temperature throughout the night on the bed, so we can note whether any cooling features were observed.

✔️ Sleep quality: Reviewers let us know if the mattress has had any effect on their sleep, including whether they wake up sore and whether they are satisfied with the mattress overall. They also compare the mattress with other models they've owned.

✔️ Additional feedback: Testers also share any specific likes, dislikes and further comments about their experiences.

Whether shopping online or in-store, mattresses are tough to decide on. After all, there's no single mattress that's best for everyone. Here's what to consider as you search for a new bed:

✔️ Firmness level: When looking through our survey data, the biggest concern for users was finding a mattress with the right firmness level. If you're unsure what firmness is best for you, here are some factors to consider in addition to any personal preferences:

✔️ Back pain: A pressure-relieving mattress, like an all-foam or hybrid style, can help provide relief for those suffering from any kind of joint pain. When we interviewed medical experts, many recommended a medium level of firmness for a balance of cushioning and support.

✔️ Temperature: Hot sleepers or anyone experiencing night sweats can benefit from a mattress with cooling properties. Some materials like memory foam are known for trapping heat, so if you're set on a foam or hybrid mattress, search for a hybrid style, which uses coils for ventilation, or a foam bed with cooling technology like phase change materials, copper particles or gel. In comparison, innerspring and latex beds tend to feel "cooler" thanks to their breathable design and materials.

✔️ Trial period: Even if you stop by a mattress store or showroom to lie on your new bed first, it's difficult to know whether a mattress is a good fit without actually sleeping on it for a few months. Because of this, most mattress companies offer an any-reason return period of at least 90 nights, so you can try your bed risk-free. But remember to check whether there are any hidden return fees and how the return process works before purchasing, just in case.✔️ Certifications: You'll likely see a few different emblems when shopping. Here are the most common certifications and what they mean:

Yes! While it's important to use a Split King mattress (two Twin XL mattresses), you also need to make sure the mattress is compatible with an adjustable bed base. Compatible mattresses are available at any firmness level or price point for the most common mattress materials.

Note that certain types, such as adjustable air, memory foam, latex and hybrid mattresses, can be more compatible due to the flexibility and durability of their materials. Many innerspring mattresses can also be a good fit, as long as they have individually pocketed coils.

Also take into account the depth of the mattress, as some bases cannot be used with taller beds (e.g., those above 14 inches in thickness). To make sure you'll be able to use a mattress with an adjustable base, it's best to contact the manufacturer.

READ MORE: The Best Mattresses for Adjustable Beds, According to Experts

Yes and no. Oftentimes, mattresses only come in one firmness. Even if a brand offers multiple firmness levels, not all split king mattresses allow you to select different firmness levels for each side. In this case, you may have to buy two Twin XL mattresses at two different firmness levels instead of a Split King to ensure each person has their preferred firmness.

We recommend sticking to the same mattress model at different firmness levels if you're going the Twin XL route. If you opt for two completely different mattresses, pay close attention to the thickness. They should be the same, otherwise, your bed may look a bit uneven.

Split King beds are equivalent to two Twin XL mattresses, so look for a Split King sheet set, which includes two Twin XL fitted sheets, one King-size flat sheet and two King-size pillowcases. If sheets don't come in a Split King size, check to see if they're available in Twin XL, which works in a pinch, especially if you plan to forgo the flat sheet, or look for a brand that lets build your own set by purchasing each component separately.

Grace Wu is a textiles product review analyst at the Good Housekeeping Institute and has evaluated tons of products using specialized laboratory equipment and feedback from hundreds of consumer testers. She's tested and written several stories on the best adjustable beds and mattresses, including the best split king adjustable beds and the best mattresses for adjustable beds. Prior to joining Good Housekeeping, Grace earned a Masters of Engineering in Materials Science & Engineering and a Bachelor of Science in Fiber Science from Cornell University.

Grace Wu (she/her) is a product reviews analyst at the Good Housekeeping Institute's Textiles, Paper and Apparel Lab, where she evaluates fabric-based products using specialized equipment and consumer tester data. Prior to starting at Good Housekeeping in 2022, she earned a master of engineering in materials science and engineering and a bachelor of science in fiber science from Cornell University. While earning her degrees, Grace worked in research laboratories for smart textiles and nanotechnology and held internships at Open Style Lab and Rent the Runway.

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