The TV musician, who has an OBE, showed off his new facial hair while visiting Royal Mail postal workers in Bristol.
Gareth formed a singing group with the staff for last year's TV series The Choir: Sing While You Work, but we're surprised they knew who he was when he walked through the door!
Standing among the men and women, Gareth showed off his ginger beard in all its glory as they posed for a picture together.
The Royal Mail Choir then shared the snap on their official Facebook site, joking: "Our old teacher dropped by to tell us we are all crap and we have ruined his career.
"After we got him his OBE. Nice beard. COUGHRobinHoodCOUGH!"
Proving there are no harding feelings, Gareth has since tweeted a picture of a can of ginger beer, adding: "Ginger beer(d)."
Meanwhile, Gareth - who achieved a Christmas No1 with the Military Wives in 2011, has also vowed to keep Simon Cowell and the X Factor winner off this year's festive top spot too.
Gareth has formed a new choir, Voices, and teamed up with composer Paul Mealor - who composed the Military Wives' single 'Wherever You Are'. His motet 'Ubi Caritas et Amor' was also performed at Prince William and Kate Middleton's wedding.
"I've hand-picked a choir of talented young singers and we've recorded Mealor's arrangement of Now Sleeps The Crimson Petal, a Tennyson sonnet," he told The Sun.
"I think it's got a good chance to be the Christmas No1."
Listen to the Military Wives' No1 'Wherever You Are' below.
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