The difference between a twin and a twin XL mattress is in the length:
- A twin mattress is 39 inches wide by 75 inches long
- A twin XL mattress is 39 inches wide by 80 inches long
The extra length makes the twin XL mattress and bedding more comfortable for older teens and adults, especially if they are tall. That is why twin XL mattresses are commonly used in college dormitories.
The extra length of a twin XL mattress means that you should look for bedding with sufficient length to accommodate the larger size, especially for mattress pads and fitted bottom sheets. Some sources use the same dimensions for twin and twin XL flat sheets, blankets and comforters. While exact measurements of the mattress and the bedding components vary from one manufacturer to another, the average size comparisons are as follows:
Mattress Pads and Fitted Sheets
- A twin mattress pad is 39 inches wide by 75 inches long
- A twin XL mattress pad is 39 inches wide by 80 inches long
These measurements refer to the top dimensions of the mattress pad or fitted sheet after it has been stretched over the mattress. To get a mattress pad or fitted sheet that fits well, you must also know your mattress depth, or thickness, and select a pad or fitted sheet with an appropriate pocket depth:
- A standard -depth mattress is 7 to 9 inches thick, and it requires a standard pocket depth of 7 to 14 1/2 inches.
- A deep mattress is 10 to 15 inches thick, which requires a pocket depth of 10 to 15 inches.
- An extra-deep mattress is 16 to 22 inches deep, requiring a pocket depth of 16 to 22 inches.
Flat Sheets, Blankets and Comforters
Twin flat sheets are typically 66 inches wide by 96 inches long. Some manufacturers provide the same size for twin XL flat sheets, so the two sizes may be used interchangeably. Other manufacturers provide longer sheets, up to 102 inches long, for twin XL sizes.
Twin blanket sizes average 66 inches wide by 90 inches long. The same size is used for twin XL mattresses, so the two sizes are equivalent.
Twin comforters are usually 68 inches wide by 88 inches long. Twin XL comforters are 68 inches wide by 90 inches long, or they may be longer.