The Inception actor landed the Rising Star Award ahead of fellow nominees Andrew Garfield, Emma Stone, Aaron Johnson and Gemma Arterton - but he was not at the ceremony to claim his prize.
Hardy admits he chose to miss the BAFTAs to go on holiday with fiancee Charlotte Riley and his son, Louis, from a previous relationship - because he never expected to land the prize.
He tells U.K. TV host Alan Carr, "I was about to go away to Georgia for six weeks and start a new film. I had a choice whether to go away before with my missus and my little boy or go to the BAFTAs.
"We watched it on TV and I was like, 'Oh no!' I never expected to win so thank you."
Carr presented Hardy with the award during an interview, which is set to air in the U.K. on Monday (21Feb11).