Olympics organisers and a Greek bank have agreed a $72m (£50m) sponsorship deal, one of the largest for the 2004 Games.
Alpha Bank outbid four other banks for the right to use the Athens 2004 logo and take part in other programmes.
Alpha will provide technical support for the Olympics.
Organisers also agreed to a $17m (£12m) deal with Athinaiki Breweries, which has the license for Heineken and Amstel in Greece.
Other major sponsors include Swatch and the state telecommunication company OTE.
Michael Payne, marketing director for the International Olympic Committee, called the new deals "phenomenal" and said they provide "clear evidence of the confidence that the business community has about the Athens 2004 Games."