Cadbury has turned its annual pop-up post office, from which people can send a bar of chocolate anonymously to a loved one, into a virtual one in the face of the Covid-19 challenges.
The online service will run from 2 to 13 December, and this year will include donations to The Trussell Trust, a charity that works to stop UK hunger.
"The Cadbury Secret Santa postal service", which launched in 2018 and visited 10 locations around the UK, also ran last year. It has been delivered by Bearded Kitten.
The activation is part of Cadbury's wider "Secret Santa" campaign, created by VCCP. The work has been running on TV, out of home and digital channels since 9 November.
Paola Cassinelli, senior brand manager for Cadbury Christmas, said: "We can't wait to bring our Secret Santa campaign online and give everyone the chance to send chocolate secretly to someone they love.
"It's been a particularly tough year for many, which is why we felt it was more important than ever to bring back our activation and let people secretly give to those they know and love, and to those who might really appreciate a small treat this Christmas."
Cadbury will also be donating Advent calendars, selection boxes and biscuits to food banks.