Mockridge studied at high school in Mount Kisco.
Mockridge began his career as a reporter for the weekly Mount Kisco Recorder in 1933. Three years later he took a position of a critic and city editor of the White Plains Daily Reporter. Then in 1940, Norton was appointed an editor of the New York World-Telegram, where he served until 1966. In 1942, he joined the United States Army and rose to first lieutenant.
In 1956, Mockridge became a city editor of the World-Telegram & Sun. He served as as a columnist of that newspaper from 1963 to 1966. In 1966, Norton held a position of a syndicated humor columnist for United Feature Syndicate and Scripps-Howard Newspapers, where he had worked for fourteen years. In addition, he hosted a daily radio show on WCBS in 1963-1964 and on the CBS Radio Network from 1964 to 1970.
Mockridge was a member of Silurian Society, New York Veterinary Police Association and Sigma Delta Chi Clubs: Players, Dutch Treat, River, Coffee House, Regency, Casino.
In 1978, Mockridge filed an age-discrimination suit against the Scripps-Howard Newspapers, charging that he had been pushed into premature retirement at age 63. The suit was settled out of court.
In 1946, Norton Mockridge married Margaret Gleason, with whom he divorced in 1961. They have three children, eight grandchildren and one great-grandchild. In 1963, he married Valborg Palmer.