Patrick was the eldest of the three sons of Ludovic Heathcoat-Amory who died of wounds in 1918, and his wife Mary Stuart Bannatyne. He was born at Chevithorne Barton, Tiverton.

Like his brothers, he was educated at the Malthouse School, Langton Matravers and Eton. He Matriculated in 1930 and followed his father to Christ Church.  He was President of the Carlton Club and the University Conservative Association. From 1932-34 he served in the University Air Squadron. He graduated with a 2nd in PPE in 1934.

He was Called to the Bar and on 7 January 1937, he attended a secret meeting of the Palestine Royal Commission when evidence was taken from David Ben-Gurion in his position as Chairman of the Executive of the Jewish Agency.

The Conservative Party selected him as their candidate for the Bridgewater constituency in the September 1938 Election. As a local man, it was thought that he was assured of a sizeable agricultural vote as half of the electorate lived in rural areas. However, he lost to the well-known broadcaster, Vernon Bartlett, who opposed appeasement.

In 1934, he had joined the Royal Devon Yeomanry, a territorial regiment He was Gazetted Lieutenant in the Royal Artillery on 3 March 1939 and promoted to Captain on 23 August.

He was serving in North Africa, seconded to the 2 Indian Field Regiment when he was killed on 27 May 1942. Initially, he had been reported missing and it was thought that he had been taken prisoner.

He is commemorated on the Alamein Memorial, Column 31 and on the Malthouse School Memorial in St. Georges Parish Church, Langton Matravers and in the Royal Memorial Chapel, Sandhurst.