The Co-operative has selected the Carers Trust as its charity of the year for 2013 and set a fundraising target of £5m.
Carers Trust works was formed in April this year when The Princess Royal Trust for Carers and Crossroads Care merged. In Scotland, it is known as the Princess Royal Trust for Carers in Scotland.
An estimated 100,000 Co-op staff are expected to get involved in the partnership, which will raise money to help provide breaks for carers, and provide information, advice and support for young adults with caring responsibilities.
The Co-op’s last charity of the year partnership with Mencap and its sister charity Enable Scotland raised £7.2m for young people with a learning disability and won a Third Sector Excellence Award this year for corporate partnership.
Thea Stein, chief executive of Carers Trust, said: "We are absolutely delighted, we believed that something extraordinary needed to happen to achieve a UK-wide profile for our cause and, this is it.
"Our partnership with the Co-operative will focus on the lives of young adult carers and the money raised will transform many of these young people’s lives. It will also take the hidden issue of unpaid carers to centre stage.
Peter Marks, group chief executive of the Co-op, said: "Caring is often a hidden issue and our partnership with Carers Trust aims to change that."