In 1942 he acted on the West End stage in The Doctor's Dilemma and in 1942 he made an uncredited film appearance in Fanny by Gaslight.

The show was unusual for the time in that it was largely improvised—with the tape subsequently edited for broadcast by Frank Muir and Denis Norden, who also sometimes took part.

These comic monologues are the fictional memoirs of an actor and producer working in British theatre and film from the 1940s to the 1980s; the stories being partially based on his own career.

[citation needed] On television, Jones was best known for his lead role as Mr Fenner in the comedy series The Rag Trade (BBC TV 1961–63, LWT 1977–78), but he also had acting roles in the British comedy series Beggar My Neighbour, The Goodies, the courtroom drama Rumpole of the Bailey, Holby City, Whoops Apocalypse, The Bill, Midsomer Murders, Minder and two episodes of The Avengers.

He also starred in the filmed comedy series From a Bird's Eye View (1970), a vehicle for Millicent Martin, in an attempt to break into the American market.

From 1969 to 1971, Jones starred opposite Sheila Hancock in a sitcom (for ITV, by Yorkshire Television) called Mr Digby Darling, lasting for three series (and 19 episodes).

An occasional scriptwriter, Jones co-wrote and starred in the sitcom Mr. Big (1977), with Ian Lavender, Prunella Scales and Carol Hawkins.

[9] Jones featured in a number of films, including Private's Progress (1956), School for Scoundrels (1960, reprising his Dudley Grosvenor character as a used-car salesman with Dennis Price), Just like a Woman (1967) alongside Wendy Craig, The Return of the Pink Panther (1975) and Chariots of Fire (1981).