John Clark, 67, volunteers one day a week with the Hearing Dogs for Deaf People, following his retirement in 2012.
Mr Clark, from Blagrove Lane, chose the charity as it was one already close to his heart.
He said: “My mother, who was deaf, had a hearing dog named Lulu about 15 years ago. Lulu not only changed her life, but also had a huge impact on every member of close family and friends as well.”
With a background in IT, he was spotted by the fundraising department, and now spends one day a week specialising in the puppy sponsorship scheme.
Mr Clark added: “My favourite part of being a volunteer is feeling like part of ‘the team’.
“However, the underlying joy is knowing that I am contributing to making a difference to all those people, like my mum, whose lives improve when they are paired with their own hearing dog.”
Becky Moorcroft, fundraising executive at Hearing
Dogs for Deaf People, said: “John is brilliant. He is so helpful and he keeps the whole office in check.
“He is known for his wicked sense of humour, and he can be very cheeky at times, but he gets away with it by treating the team with doughnuts now and then!”
Coinciding with National Volunteers Week – which runs until Saturday – he will receive a special thanks from the chief executive, Michele Jennings, and treated to cakes from staff.