Mike Fiske, 57, didn't tell Jane, 58, for a whole week as he was convinced the email confirming his jackpot was a joke or spam message.
The oil firm geophysicist had entered the EuroMillions Lucky Dip online on 28 November and received a message the next day that revealed he'd won the dosh.
But the sceptical chap didn't believe the win until the following Friday, when he made a trip to the Camelot office and received confirmation in person.
He finally broke the news to Jane, his partner of 28 years, when he returned to their Norwich home.
He was quoted in The Sun discussing his initial doubts: "When I got the email I wanted to believe it but the cautious side of me kept thinking it must be a joke. When I finally realised I had won it felt euphoric.
"As I walked through the door, I said, 'I've got some good news, we've won £1million.' She was absolutely bowled over."
The couple - who have two adult children - plan to finish building a new house and travel the world.
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