Late Show with David Letterman, a talk show airing on CBS since 1993

David Letterman, a television talk show host

Late Night with David Letterman, a talk show airing on NBC from 1982 to 1993

The Lettermen, a musical group

Mail carrier

Letterman, a classification of high school or college athlete in the United States

William Henry Letterman, co-founder of the Phi Kappa Psi fraternity and brother of Jonathan

Jonathan Letterman, an American surgeon known as the "Father of Battlefield Medicine"

Letterman Army Hospital, a hospital operating from 1898 to 1995 on the Presidio of San Francisco

The Adventures of Letterman, a segment on the children's show The Electric Company

Letterman Digital Arts Center, the home of several Lucasfilm units, located on the site of the former Letterman Army Hospital