A national bank holiday should be created to encourage more people to volunteer in their communities, unions and charities say.
Girlguiding UK wants to encourage more volunteers
The TUC and a number of voluntary organisations claim the day would also be a chance to celebrate the unpaid work already done across the UK.
Campaigners want to see Community Day created at the end of October.
They say it should appeal to Gordon Brown, who has said he would like a national day to celebrate Britishness.
TUC General Secretary Brendan Barber said it was "a great opportunity" for Mr Brown as the new Prime Minister "to make a mark in history".
"This is an idea whose time has come," Mr Barber said,
"It will encourage more community involvement, celebrate our shared values as a nation, and help meet the holiday gap between Britain and the rest of Europe, but in a constructive way."
Dame Elisabeth Hoodless, executive director of volunteering and training charity CSV, said research showed that 11 million people in Britain would volunteer if asked.
"A community day is an excellent way to involve them to reduce crime, boost health, protect the environment and help young people to read and write," she added.
And Christopher Spence, chief executive of Volunteering England, said the bank holiday would be a chance to recognise the contributions made by people, unpaid, to their communities.