5 signs you need a split California king mattress not a split king

A couple smile while drinking coffee in split Cal king mattress
(Image credit: Getty Images)

Split king mattresses are great for couples who want to customize their side of the bed and don't want to feel their partner's movements during the night. However, a split California king mattress can offer the same benefits and may even be better for some couples. But what are the signs that you need a split Cal king instead of a standard split king?

A lot of our picks in this year's best mattress guide come in a split king size, but some also offer a split Cal king, too. While they can be harder to find than a standard split king, split Cali kings can be worth looking for if you have certain sleep needs.

Here, we've rounded up the five key signs that you and your partner would be better off with a split Cal king than a split king mattress. Plus, we've also found some of the best split Cal king bed deals in this month's mattress sales for you to shop now. 

What is a split king mattress?

A split king mattress has the same dimensions as a standard king mattress  — measuring 76 inches wide and 80 inches long  —  but instead of one big mattress, it is made up of two separate twin XL mattresses pushed together.

A Saatva Split King Mattress inside a luxe hotel room

(Image credit: Saatva)

Two separate mattresses mean there is more motion isolation for couples, which is ideal if your partner is a restless sleeper or works on a different sleep schedule to you. It's also a great set-up for couples with different body types and sleep positions, as you can customize the firmness levels on each side of the bed for individualized comfort.

What is a split California king mattress?

A split Cal king mattress is, like a standard Cal king mattress, 72 inches wide by 84 inches long. This means a split California king is narrower but longer than a split king mattress, with each mattress measuring 36 inches wide and 84 inches long. They can be harder to find than a standard split king, but they are becoming more popular and widely available.

5 signs you need a split California king mattress not a split king

1. One (or both) of you is taller than 6'2"

If you or your partner is over 6'2" and it feels like your feet are dangling over the bed while sleeping flat on your stomach or back, it could be that a split king is too short for you. A split Cal king, on the other hand, is more suitable for taller individuals as they are longer than split kings. 

2. You don't take up too much space

Two women laugh and talk while lying on a split king mattress

(Image credit: Getty Images)

Some sleepers have a large build or like to spread out when they sleep, meaning that a wider split king is a better option. However, if you and your partner have slim to average builds and sleep in a position that doesn't take up too much room, a narrow Cal king will work just fine. 

3. You have a narrow but long bedroom

A bearded man measures a wall with his partner holding the measuring tape

(Image credit: Getty Images)

If you want to know how to choose a mattress, the first thing to consider is what size mattress will suit and fit your room. There's no point trying to cram the biggest mattress size into a room that's too small. Split king mattresses work better in bedrooms that are narrow and long than standard split kings, allowing for extra room on the sides. 

4. You have no co-sleeping children...

Woman looks at her sleeping partner in bed

(Image credit: Getty/Maskot)

A lot of parents are opting to co-sleep with their young children, which requires a wider surface. While king mattresses are best for co-sleepers, split king mattress aren't ideal for co-sleeping families as they're only designed to accommodate couples. 

If split king mattresses aren't appropriate for co-sleeping families, then split Cal king beds definitely won't be. That's why split Cal kings are perfect for couples only. 

5. …but do co-sleep with pets

A couple lie in bed with their dog sleeping at the foot of the bed

(Image credit: Getty Images)

While split Cal king mattresses (and split kings) may not be suitable for families, they are great if you want to shared a bed with your pet. A split Cal king's longer frame means that there'll likely be more space at the foot of the bed for your four-legged friend to take a nap without taking up too much space between you and your partner. 

3 Split Cal king mattresses to shop right now

1. Split Cal King Nolah Natural Mattress: was $3,398 now $2,298 at Nolah

1. Split Cal King Nolah Natural Mattress: was $3,398 now $2,298 at Nolah
The Nolah Natural earns a place in this year's best organic mattress guide for its great back pain support, naturally cooling materials, and relatively affordable pricing for a natural latex mattress. The only downside is that there's no firmness options to choose from, so you won't be able to customize the firmness on your side of the bed. Right now, you can save $1,100 on a split Cal king when you use the code TOMSGUIDE50 at checkout. You'll also get a 120-night sleep trial, free shipping, and lifetime warranty.

2. Split Cal King Sleep Number i8 smart bed: was $5,799now $4,349 at Sleep Number  

2. Split Cal King Sleep Number i8 smart bed: was $5,799 now $4,349 at Sleep Number  
The i8 smart is considered one of the best smart beds on the market thanks to its adjustable firmness, breathable design, and app-controlled in-built technology that tracks your sleep gives you personalizes insights into your health. Right now, there's a 25% off sale that takes 1,450 off the split Cal king size.

3. Split Cal King Brooklyn Bedding Signature Hybrid Mattress:was $832 now $582.40 at Brooklyn Bedding

3. Split Cal King Brooklyn Bedding Signature Hybrid Mattress: was $832 now $582.40 at Brooklyn Bedding
The Signature Hybrid is a great choice if your looking for a Split King mattress as it comes in three different firmness levels, so you and your partner can customize your side of the bed. Our testers for the Brooklyn Bedding Signature Hybrid mattress review also praised the supportive and bouncy feel, but be aware that some may find it too warm. Extras include free shipping (returns cost $99), 120-night sleep trial, and a 10-year warranty. 

Frances Daniels
Senior Sleep Staff Writer

Frances Daniels is a PPA-accredited journalist and Sleep Staff Writer at Tom's Guide with an MA in Magazine Journalism from Cardiff University. Her role includes covering mattress and sleep news and writing sleep product reviews and buyer's guides, including our Best Hybrid Mattress 2025 guide. She is hugely interested in the relationship between good sleep and overall health, interviewing a wide array of mattress and sleep experts to create well-informed articles about important topics such as nutrition, sleep disorders (from sleep apnea to night terrors), lucid dreaming, sleep hygiene, and mattress care. She is also our specialist on mattress toppers — producing mattress topper reviews and taking care of our Best Mattress Toppers 2025 guide — and takes the lead on all content related to fiberglass-free mattresses for a clean, non-toxic sleep. Outside of Tom's Guide, she has written for Ideal Home, Homes & Gardens, and Marie Claire. 

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