What Is a Split California King Mattress?
A Split California King consists of two mattresses, each 36 inches wide × 84 inches long. When placed together, they create the same sleeping surface as a standard California King (72" × 84").
| Size | Width | Length | Notes |
|---|---|---|---|
| California King | 72" | 84" | Single mattress |
| Split California King | 72" (36" × 2) | 84" | Two separate mattresses |
| Split King (different) | 76" (38" × 2) | 80" | Two Twin XLs — NOT the same |
Important: A Split Cal King is NOT the same as a Split King. Split King uses two Twin XL mattresses (38" × 80" each). Split Cal King halves are narrower but longer (36" × 84" each). That 36" × 84" size doesn't match any standard mattress dimension, which is why finding accessories like sheets and toppers is challenging.
Why Split California King Mattresses Are Hard to Find
Split King is everywhere — you can walk into any mattress store and find options because it uses standard Twin XL mattresses.
Split California King? Most retailers don't stock it. Many salespeople don't even know it exists. The 36" × 84" dimensions are unique to this size and don't match any standard mattress.
From my removal work, here's what I see: We often pick up only ONE half of a split setup. Usually it's the heavier person's side that wore out first — body impressions and sagging on their half while the other still has years left. If both halves are the same mattress, couples should swap sides periodically for even wear, but most people don't do this.
Who Needs a Split California King?
Based on the Split Cal King mattresses I've removed over the years, owners typically fall into these categories:
Couples with adjustable bases who want independent movement — This is the most common scenario. Split adjustable bases let each person raise their head or feet independently. One partner can sit up reading while the other sleeps flat. You can't do this with a single-piece mattress — it would buckle.
Couples with different firmness preferences — One likes firm, the other likes soft. With a split setup, each person can choose their own firmness level.
Taller individuals who need the extra length — California King is 84 inches long — 4 inches longer than a standard King. If you're over 6 feet tall and your feet hang off a regular King, Cal King solves that. The split version adds adjustable base compatibility.
Where to Buy Online
Online is where you'll find the widest selection of Split California King mattresses. These retailers specialize in custom and odd sizes.
Brooklyn Bedding
5 Mattresses Available in 36×84 Split California King
Brooklyn Bedding manufactures their own mattresses in Phoenix, Arizona. They've been making mattresses since 1995 and own their factory — one of the few brands that actually manufactures in the US.
RVMattress.com
1 Mattress Available in 36×84 Split California King
RVMattress.com is run by Brooklyn Bedding and offers budget-friendly options in Split Cal King.
PlushBeds
1 Mattress Available in 36×84 Split California King
PlushBeds offers organic and natural latex mattresses in Split Cal King — one of the few options for eco-friendly materials in this size.
Mattress Insider
Mattress Insider specializes in custom-size mattresses and can make Split Cal King in various constructions — memory foam, latex, and custom configurations.
Amazon
Amazon carries some Split Cal King options, though selection is limited compared to other sizes. Search "Split California King mattress 36x84" to see current options.
Note: Verify exact dimensions (36" × 84" per half). Some listings labeled "Split Cal King" are actually Split King (Twin XL dimensions). Quality varies significantly.
Where to Buy In-Store
Finding a Split California King mattress in a physical store is challenging because most showrooms only stock standard sizes. Here are your options:
Brooklyn Bedding Showrooms
Brooklyn Bedding operates showrooms in Arizona, Utah, and Minnesota where you can try their mattresses in standard sizes. The feel is identical in Split Cal King — only dimensions change.
Find locations: brooklynbedding.com/pages/showrooms
SleePare Showrooms
SleePare is a multi-brand showroom in New York, Dallas, and Los Angeles that carries Brooklyn Bedding. You can test mattresses in person, then order your Split Cal King size.
Website: sleepare.com
Local Custom Mattress Shops
Some local mattress makers can produce 36" × 84" mattresses. Search for "custom mattress" + your city.
Split Cal King Accessories
Sheets
Finding 36" × 84" fitted sheets for each half is challenging. Options:
- Search "Split Cal King sheets" on Amazon — Some manufacturers make specific sets
- Brooklyn Bedding — Offers sheets in custom sizes
- Use Twin XL sheets — They're 38" × 80" (slightly wider, 4" shorter), so they won't fit perfectly but work in a pinch
Tip: California King flat sheets work for the top since Split Cal King combined is 72" × 84".
Mattress Bridges
If you're concerned about the gap between the two halves, mattress bridges (foam gap fillers) can help. However, they don't work well with adjustable bases since they'll shift when the bed articulates.
Mattress Toppers
Search for "Split California King mattress topper" or buy two 36" × 84" toppers. Some couples use a single Cal King topper across both halves to create a more unified feel — this works if you don't use the adjustable feature frequently.
Before You Buy: Important Considerations
Adjustable Base Compatibility
If you're buying for an adjustable base, confirm:
- Your base is Split California King (not Split King)
- The mattress works with adjustable bases (hybrids and all-foam typically do; innerspring may not flex well)
- The mattress height doesn't interfere with your base's movement
Matching Heights
If buying two different mattresses (different firmness per side), make sure they're the same height. Different heights create an uneven surface and look strange.
Swapping Sides
Since I often see one half wear out before the other (usually the heavier person's side), consider swapping sides every 6-12 months if you have identical mattresses on both sides.
What I Look For (Based on 1M+ Mattresses Removed)
After removing over a million mattresses — including Split Cal King setups — here's what separates mattresses that last from those that fall apart in 3-4 years:
Foam Density Matters
Low-density foam (under 1.5 PCF) breaks down quickly. High-density foam (2.0+ PCF) holds up for years. Ask about density or look for specs that mention "high-density support foam."
Coil Gauge Matters
In hybrid and innerspring mattresses, lower gauge numbers mean thicker, more durable coils. 15-gauge is solid. 18-gauge is flimsy. I regularly tear apart mattresses and see the difference firsthand.
Avoid Fiberglass Fire Barriers
Many budget mattresses use fiberglass as a fire barrier. If the tag says "do not remove cover," it likely contains fiberglass. Avoid these. Look for CertiPUR-US certification and brands that explicitly state they're fiberglass-free.
Split Setups Wear Unevenly
Real observation from my work: With split mattresses, I regularly pick up just ONE half — the heavier person's side wore out while the other half still had years left. Body impressions and sagging develop faster on one side. If you get identical mattresses, swap sides every 6-12 months to even out wear.
FAQ
What size is a Split California King mattress?
Two mattresses, each 36" wide × 84" long. Combined, they equal a standard California King (72" × 84").
Is Split Cal King the same as Split King?
No. Split King uses two Twin XL mattresses (38" × 80" each). Split Cal King halves are narrower but longer (36" × 84" each). They're not interchangeable.
Can I use two different mattresses in a Split Cal King setup?
Yes, as long as they're both 36" × 84" and the same height. Many couples choose different firmness levels for each side.
Why would I choose Split Cal King over Split King?
If you need the extra 4" of length (84" vs 80") — typically for sleepers over 6' tall. Or if you already have a Split Cal King adjustable base or bed frame.
Can I try a Split Cal King before buying?
Most online retailers offer 100-365 night trial periods. Brooklyn Bedding showrooms let you try standard sizes in person — the feel is identical, only dimensions change.
How long do Split Cal King mattresses last?
With quality materials, 7-10 years for nightly use. I often see one half wear out before the other — consider swapping sides periodically for even wear.
What to Do With Your Old Mattress
When you buy new Split Cal King mattresses online, you're left to figure out what to do with the old ones.
Need Your Old Mattress Removed?
Getting rid of an odd-size mattress can be tricky. I've put together a complete guide to your disposal and recycling options.
See Your Options →About This Guide
