It will take him to the conclusion of Rugby World Cup 2007.
D'Arcy's commitment to Leinster and Irish rugby follows contractual agreements already put in place with all of Ireland's leading players.
Philip Browne, Chief Executive, IRFU says: We are delighted that Gordon D'Arcy has now added his name to the long list of fellow Irish international players, who have also pledged their immediate futures to Irish rugby.
It is the on-going determination of the IRFU to keep the leading players at home and manage their welfare, so that when they take to the field they are more likely to be in the best possible state. It is, therefore, most pleasing to have the co-operation and support of the players in the best interests of the game in Ireland.
Gordon D'Arcy says: This is one of the best eras we have had in Irish rugby and with our recent success in the Triple Crown and twice finishing runners up in the Six Nations championship, I feel it is an appropriate time to pledge my future to Leinster and Irish rugby and help build on our successes into World Cup 2007.