Join In received the funding after making an application to the Big Lottery Fund’s Spirit of 2012 Trust, which will get between £30m and £40m from the sale of the Olympic Village.
Join In will use part of the £1.5m to stage a "go local" event in July, aimed at encouraging London 2012 volunteers, such as Games Makers and London Ambassadors, to be more active in their local communities.
The event, which is supported by Team London, the Mayor of London’s volunteering initiative, will take place on 19 July in the Queen Elizabeth Olympic Park in east London. It will feature musical acts and will offer practical advice on volunteering.
The rest of the £1.5m will be used to support three further Join In projects throughout 2013. The charity will run a nationwide campaign to encourage sports clubs and community groups to offer volunteering opportunities through its website.
It will also run a programme to inspire people to volunteer in their local clubs and communities and a campaign to change people’s perceptions of volunteering.
Research carried out recently by Join In found that 84 per cent of sports clubs felt they needed more volunteers to help them function, and 87 per cent thought a lack of volunteers prevented them from increasing membership levels.
Sir Charles Allen, chair of Join In, said the event was a chance for the charity to encourage local volunteering. "Clubs are telling us that they are in something of a catch-22 situation," he said. "Many of them experienced a boost in participation and interest, but they simply don’t have the resources to cope with it.
"The Games Makers and other volunteers were rightly lauded last summer, but many of them have yet to continue what they started. The event is a chance to get them back together and ask them to play an active and significant role in the legacy of the Olympic Games."
Nick Hurd, the Minister for Civil Society, said: "We want to harness the spirit of the 2012 games and ensure that they are the catalyst for a great volunteering legacy in this country."
Tickets for the event in July will go on sale at the end of May, with priority given to Games Makers, London Ambassadors, Ceremony Volunteers and City Ambassadors.