Mercer has received more than 25 Gemini Awards for his television work. He has also been a winner of the prestigious Sir Peter Ustinov Comedy Award, presented to him at the 2003 Banff Television Festival. In 1993, Newfoundland premier Clyde Wells honoured Mercer with the Newfoundland Arts Council's Artist of the Year award. In 2004, Mercer was presented with the National Arts Centre Award, a companion award of the Governor General's Performing Arts Awards. He donated his $15,000 cash prize to the LSPU hall, the theatre in Newfoundland where Mercer performed his early work.