Twin XL

Longer in length than a regular Twin-sized mattress, the Twin XL provides comfort and support that's ideal for dorm rooms, a split-King setup, or tall people.

Serta Mattress


Serta Arctic Hybrid Mattress
Serta Arctic Hybrid Mattress

$2,299.00 $2,999.00

Serta Arctic Mattress
Serta Arctic Mattress

$2,299.00 $2,999.00

Serta iSeries Hybrid


Why You Should Buy a Twin XL Mattress

Twin XL mattresses are commonly chosen by those who desire extra legroom compared to a standard twin bed. With the same width as a twin, a twin XL mattress provides an additional 5 inches in length, measuring approximately 38" wide by 79.5" long, give or take a ½ an inch. This extended length makes it a suitable option for taller individuals or those who prefer more sleeping space to stretch out. Twin XL beds are frequently found in college dorm rooms as they offer a comfortable solution for students without taking up too much of the room space. They are also used in split king setups. Serta offers a variety of twin XL mattresses, including memory foam, mattress in a box, hybrid and innerspring options, ensuring that you can find the perfect Serta twin XL mattress to match your comfortability and needs.

Twin XL Frequently Asked Questions:

What size is a twin XL mattress?

Approx. Size: 38” x 79.5” / 3,021 sq in / 21 sq ft

Twin XL sizes are approximately 38” wide by 79.5” long, give or take a ½ an inch, which equates to approximately 3,021 sq inches and 21 sq feet.

What's the size difference between twin xl and twin sizes?

A twin is the same width but approximately 5 inches shorter than a twin XL.

Can two twin XL mattresses be used to create the same size as a queen or king mattress?

Yes, two twin XL mattresses placed side by side will create the same size as a king mattress. Also, two twin XLs make a split king.

What is a split king?

A split king bed is composed of two twin XL mattresses placed side by side on a single bed frame. While it has the same dimensions as a regular king, measuring 76 inches wide by 79.5 inches (give or take a ½ inch) long, the key difference is that it consists of two completely separate mattresses instead of one. This allows for customization and comfort preferences for each sleeper on their side of the bed.

Can a twin XL mattress fit on a twin-sized bed frame?

No, due to the slight difference in length, a twin XL mattress is not compatible with a standard twin bed frame as it will be too long.

Is twin XL the same size as a full bed?

No. A full size mattress is 15 inches wider and a twin XL is longer by 5 inches.

Can I expedite my order?

We do not have an expedited delivery option at this time. Our site will provide the best delivery estimate at checkout.

Do you ship internationally?

Directly on our website, we only ship within the United States, to the lower 48 states. At this time we do not offer shipping to Alaska or Hawaii.

Do you offer financing?

Financing is available directly through our website. We have partnered with Affirm to offer financing or pay-over-time options for our customers. At checkout, you will be given the option to pay through Affirm. If approved, you will be given loan options for 3, 6, or 12 months. All interest is provided up front, there are no hidden fees, and only a soft credit check is done through Affirm's system for approval. After you've confirmed your choice, you will be redirected back to our website to complete checkout.

Affirm only requests a soft credit check for approval, so the credit inquiry won’t affect your credit score. Once you've selected your financing term, you will be redirected back to the website to complete your purchase.

For returns and cancellations, refunds will be processed through Affirm and posted to your Affirm account. Refunds will be processed within 3-10 business days. Keep in mind the interest charge will not be refunded.

Please note that financing through Affirm is not available in West Virginia and Iowa.

What is the difference between ordering from and another retailer?

When you place an order through, you are backed by the 120-Day In-Home Trial. We know ordering a mattress online can be intimidating, so we want to take the risk out of it for you with the in-home trial that allows the perfect amount of time to test the mattress and accessories in your home and make sure it's right for you. If you decide it is not the right fit, we make returns easy and free.

Serta products are sold at many different retailers through the United States. Our goal is to be able to serve our sleepers where they feel the most confident purchasing their Serta products. Many retailers will have products on display for sleepers to test out before making your decision, and may offer different pricing or promotional advantages for buying directly through a retailer. Retailers may also have different models than what you see directly on the website.

Regardless of where you purchase, you can be confident you are getting a quality Serta product.

Do you make custom sizes?

We are unable to provide custom sizes at this time. For now, we carry industry standard sizes of twin, twin XL, full, queen, king, and California king.

Why buy Serta online?

120-Day In-Home Trial

Experience the mattress in your home for up to 120 days. If you’re not completely satisfied, you can exchange or return it for a refund.

Read more


You should be able to rely on the quality of your rest night after night. That’s why every Serta® mattress is backed by Serta’s 10-year limited warranty.

Read more

Free Shipping & Returns

All mattresses and foundations ship free and feature free returns when you order directly from

Read more


All Serta mattresses are designed and assembled in the USA, leveraging our 85 years of manufacturing expertise.

Read more

certipur-us® certified

Rest easy knowing Serta uses only CertiPUR-US® Certified Polyurethane Foam.

Read more
Family, woman on the left, young son in the middle and man on the right laying on a mattress asleep

Try in stores

Want to test our products before you buy? Our Sleep Ambassadors will offer you a personalized, no-pressure in-store experience. Don't live near a Serta shop? Learn where else you can find us!

Join our email list

Sign up for new arrivals, special offers and tips for better sleep.

There was an error. Please try again.

Privacy Notice