The measurements for twin XL bed sheets are 39 by 80 inches. XL stands for extra long, and the bed sheets may be otherwise identified as TXL, extended twin or extra-long twin.
Measurements for a twin XL bed sheet is the same width as a standard twin mattress, but is 5 inches greater in length. XL twins are often found in college dorm rooms to accommodate young adults. When one is choosing a comforter, duvet cover, blanket or bed spread to pair with twin XL bed sheets, it should measure 68 by 90 inches or longer.