Differdange 03 was formed in 2003 as an amalgam of two clubs from the city of Differdange: FA Red Boys Differdange and AS Differdange.
FC Differdange 03 vznikl v roce 2003 sloučením dvou klubů z města Differdange: FA Red Boys Differdange (Football Association Red Boys Differdange) a AS Differdange (Association Sportive Differdange).