The City of London firms are linking up with Save the Children in a special appeal for the children of Kosovo.
The focus of the appeal will be Tuesday July 6 which has been designated 'K day' in the City.
The charity is appealing for donations of unwanted foreign coins built up through business travel abroad to fund its work in the Balkans.
Organisers hope the City firms will become actively involved in the event and allow fund-raisers access to all areas of their business, to maximise the money raised.
Save the Children is encouraging people to donate an hours or even a days salary to the appeal. It is also hoping firms will either meet or beat the donations made by their staff.