Fast Facts about Twin Box Springs (Your FAQs)

We’ve seen a lot of questions about box springs, so we wanted to answer them for you in one spot.  Keep reading for fast facts and Q&A about box springs for twin beds.

What is the point of a box spring?

There is more than one purpose for a box spring:

  • Provides support for the mattress
  • It works as a shock absorber for the mattress, reducing the impact
  • Lifts the mattress to a more comfortable height
  • Increases airflow, keeping the mattress cooler


Is it OK to sleep without a box spring?

No, you don’t specifically need a box spring, but you will need some sort of foundation unless the mattress is directly on the floor. Other options depend on the type of frame used and for most frames, box spring is the most common foundation.


Can I buy just a box spring?

Yes, the box spring is sold separately as a single unit anywhere mattresses are sold. You are not required to buy both a mattress and a box spring at the same time.


Can I buy just a box spring?

There are only two reasons to specifically need a box spring as a mattress foundation.

  1. Foldable metal frames require a box spring
  2. Some mattress warranties require a box spring be used or the warranty is void


What size is a twin XL box spring?

The twin XL box spring dimensions are 39” x 80”, adding five inches to the length of a regular twin box spring which is 75” long.


Can I put a twin XL mattress on a twin frame?

Even though it’s only 5 inches longer than a twin, a twin XL mattress will not fit on a twin-sized frame. You can either buy a twin XL frame or extensions for a twin frame to accommodate.


Can 2 twin XL box springs make a king?

Yes, two twin XL box springs pushed together will be the same size as a standard king box spring, 76” x 80”.


Is Twin XL box spring the same as double?

No, a twin XL box spring isn’t the same as a double, also known as a full. A twin XL measures 38” x 80” and a double/full measures 54” x 75”.