Thompson was born in Paeroa, New Zealand, the son of Leslie Foster Thompson and Caroline Walker, and arrived in Australia aged two. He was educated in state schools before attending Newington College. In 1934 he married Constance Olive Mayhew and they had a daughter and a son.
Business career
After school, Thompson worked with Sun Newspapers Limited. He became a director of National Roads and Motorists Association Insurance Limited and Open Road Publishing Company Pty Limited.