What Size Is A Split King Mattress

If you’re looking for a flexible sleep solution for couples, you might be asking, what size is a split king mattress? Understanding its dimensions is the first step to seeing if it fits your bedroom and your sleep needs. This guide will break down everything you need to know.

A split king is essentially two separate mattresses placed side-by-side. Each side is the size of a standard twin XL. This design offers individual comfort for each sleeper.

The total dimensions of a split king mattress are 76 inches wide by 80 inches long. It is created by combining two twin XL mattresses, each measuring 38 inches wide by 80 inches long. When placed together, they form the standard king width.

This setup is perfect for couples with different firmness preferences. One side can be soft while the other is firm. It also helps with motion isolation, so you’re less likely to be disturbed by your partner’s movements.

Detailed Dimensions and Layout

Let’s look at the numbers more closely. A standard king mattress is one solid piece measuring 76″ x 80″. A split king achieves the same footprint but with a seam down the middle.

Total Width: 76 inches (6 feet, 4 inches)
Total Length: 80 inches (6 feet, 8 inches)
Individual Side Width: 38 inches (3 feet, 2 inches each)
Individual Side Length: 80 inches

You’ll need a bed frame or two adjustable bases that can accomodate two twin XL mattresses. The gap between the two mattresses can be managed with a bed bridge or a king-sized mattress pad designed for split kings.

Comparing Split King to Other Mattress Sizes

It’s helpful to see how a split king stacks up against other common sizes. This comparison can clarify if it’s the right choice for you.

Split King vs. Standard King

The overall sleeping surface is identical. The key difference is the split. A standard king is one unified piece. A split king offers individual adjustability and customization, which a standard king cannot.

Split King vs. California King

A California king is longer and narrower (72″ x 84″). A split king is wider and shorter. There is also a split California king option, which is two twin XL mattresses in length but narrower in total width than a standard split king.

Split King vs. Queen

A queen mattress is smaller, measuring 60″ x 80″. A split king provides 16 extra inches of total width, offering significantly more space for two people. It’s a major upgrade in personal sleeping real estate.

Who is a Split King Best For?

This mattress setup isn’t for everyone, but it’s ideal for specific situations. Consider a split king if:

You and your partner have very different firmness, support, or material preferences (e.g., memory foam vs. latex).
One or both of you use an adjustable bed base to read, watch TV, or alleviate snoring or acid reflux.
Motion transfer is a major issue, and you wake up easily from your partner moving.
There is a significant size or weight difference between sleepers requiring different support levels.
You have a large master bedroom that can fit the wider footprint.

Potential Drawbacks to Consider

While beneficial, split kings have some downsides. Being aware of them helps you make an informed decision.

The Gap: A slight crevice can form between the two mattresses, which some couples find annoying.
Sheet Complexity: You need special sheets: either two twin XL fitted sheets or one split king sheet set with separate bottom sheets.
Cost: It can be more expensive than a standard king, as you’re buying two mattresses and possibly two adjustable bases.
Alignment: The mattresses can shift apart over time if not properly secured on the bed frame.

How to Shop for a Split King Mattress

Follow these steps to ensure you get the right setup for both sleepers.

Measure Your Room: Ensure you have space for a 76″ x 80″ bed, plus walking room on three sides.
Choose Your Base: Decide on a split adjustable base, two separate foundations, or a single split-compatible bed frame.
Test Separately: Each person should test mattress types (innerspring, hybrid, foam) for their side. Don’t assume you’ll like the same thing.
Check Return Policies: Understand the trial period and return process for each mattress, as they may be handled separately.
Order Accessories: Remember to order the correct sheets, a mattress bridge if desired, and a king-sized mattress protector or two twin XL protectors.

Bedding and Accessories for a Split King

Getting the right bedding is crucial. Standard king sheets will not fit properly because of the split. Here’s what you need:

Fitted Sheets: Two twin XL fitted sheets. This is often the easiest and most secure option.
Flat Sheet & Bedding Covers: One standard king flat sheet, duvet, or comforter can be used on top to unify the look.
Mattress Protector: Opt for a specially designed split king protector that covers both pieces or two individual twin XL protectors.
Bed Bridge: A foam or fabric insert that spans the gap between the mattresses, creating a more seamless feel.

Making the Bed Easier

Making a split king bed takes a little more effort. Tuck the top sheet and comforter tightly between the mattresses at the center to minimize the appearance of the gap. Using a bed skirt that goes over a single box spring or platform can also help create a unified appearance.

Cost Breakdown and Investment

The cost of a split king system varies widely. You are investing in two separate sleep systems.

Mattresses: Two twin XL mattresses. Cost ranges from $600 to $3000+ each, depending on brand and quality.
Adjustable Bases: If desired, two twin XL adjustable bases can cost $800 to $2500+ each.
Bed Frame/Foundation: A compatible frame if not using adjustable bases.
Bedding: Specialized sheets and protectors are an additional, recurring cost.

While an investment, many couples find the improvement in sleep quality to be worth the expense and the extra logistical steps.

FAQ Section

How wide is each side of a split king?

Each side of a split king is 38 inches wide, which is the standard width of a twin XL mattress.

Can you use a regular king sheet on a split king?

You can use a regular king flat sheet or comforter on top. However, you cannot use a regular king fitted sheet. It will not stay secure on the two separate mattress pieces. You need two twin XL fitted sheets.

Does a split king have a gap in the middle?

There can be a small gap between the two mattresses. You can minimize this with a tight-fitting sheet setup or use a bed bridge accessory to fill the space for a more seamless feel.

What is the difference between a split king and two twin XLs?

There is no physical difference. A split king is two twin XL mattresses. The term “split king” refers to their intended use together on a king-sized bed frame or adjustable bases to form a king-sized sleeping surface for couples.

Is a split king the same size as a king?

Yes, the total overall dimensions are the same: 76 inches by 80 inches. The only difference is the split down the middle.

Are split kings good for couples?

They are excellent for couples with different sleep preferences, those who use adjustable bases, or light sleepers bothered by motion transfer. They offer personalized comfort that a shared single mattress cannot.

Final Thoughts on Choosing a Split King

Knowing the answer to “what size is a split king mattress” is just the beginning. Its unique 76″ x 80″ size, formed by two twin XL units, offers a compelling solution for personalized sleep. The benefits of individual comfort and motion isolation are significant for many couples.

However, the considerations around cost, bedding, and managing the gap are real. Carefully weigh the pros and cons based on you and your partner’s specific needs. Measure your room, test mattresses independently, and plan your bedding strategy ahead of time. With the right preparation, a split king can be a fantastic investment into better, more personalized sleep for both people sharing the bed.