William Lanteau (born William Lanctot) (November 12, 1922 – November 3, 1993) was an American character actor.

Among his best known roles are Charlie the mail carrier in On Golden Pond[1] and mayor Chester Wanamaker[2] in Newhart.

He appeared in the first season of Barnaby Jones in an episode titled "To Denise, with Love and Murder" (April 22, 1973).

He also appeared in the movies Li'l Abner (1959), The Honeymoon Machine (1961), Sex and the Single Girl (1964), Hotel (1967), From Noon till Three (1976), On Golden Pond (1981), Cold Steel (1987), and Shadow of a Doubt (1991).Other notable appearances on television included The Twilight Zone , Dr. Kildare, Perry Mason, The Man from U.N.C.L.E., The Waltons, CHiPs, Trapper John, M.D., Diff'rent Strokes, Hart to Hart, Cagney & Lacey, Cheers, Murder, She Wrote, The Wonder Years, Newhart, Amen, and Coach He died of complications from heart surgery on November 3, 1993, at age 70.

This article about an American television actor born in the 1920s is a stub.