During his high school years, Frank Cady worked for the local newspaper The Lassen County Advocate. The family later moved to Wilsonville, Oregon. He studied drama and journalism at Stanford University. During his time, he met his future wife Shirley know and wrote for the Stanford Chaparral. After graduating, he moved to London, where he performed alongside several appearances at Westminster Theatre also at the BBC. In 1939, he returned to Stanford, where he lectured. Shortly thereafter, he moved to California, where he worked as an announcer and newscaster at several radio stations. During the Second World War he served in the United States Army Air Forces as a news reporter in England, France and Germany.
After his discharge from the military in 1946 Cady moved back to Los Angeles, where he stood on the stage and was occasionally seen in smaller supporting roles in films such as The Street of the successful, Father of the Bride and The Last Day. He has established itself as an actor, playing alongside larger roles in feature film with the figure of Doc Williams in the family series The Adventures of Ozzie & Harriet, who he played in 61 episodes from 1953 to 1964, his first major role, with his him breakthrough. However, his most famous role was that of the shop owner Sam Printers that he played in a total of three different television series. He played the popular character voiced by the public in 1963 in 165 episodes of the TV series Petticoat Junction, after 1965 in 141 episodes at Green Acres and 1968-1970 in the series The Beverly Hillbillies.
On June 8, 2012 Cady died at the age of 96 years. He was married to his wife, Shirley, from 1940 until her death in 2008. Both had two children together. When he died he left behind in addition to these, three grandchildren and three great-grandchildren.