Alongside his work as an author, he taught English at High Pavement Grammar School for many years.

He was also a fine watercolourist and contributed his own artwork to the covers of the 1994 novel Catalysts and the festschrift Stanley Middleton At Eighty.

In 2006, a reporter for The Sunday Times sent the first chapters of Holiday to a number of publishers and literary agents as a journalistic stunt.

Middleton was married to Margaret Welch from 1951 until his death; the couple had two daughters, Penny and Sarah.

Towards the end of his life, he suffered from cancer, and died in a nursing home on 25 July 2009, at age 89.