The launch of iPlayer, first announced last November, replaces the selection of BBC programmes previously available on BT Vision's TV Replay platform.
A phased implementation of iPlayer on BT Vision began last December and has now reached completion, offering all of the BBC's TV and radio shows on a "simple and intuitive BBC iPlayer-branded application".
Marc Watson, the chief executive of BT Retail, said: "The launch of BBC iPlayer on BT Vision adds to the enormous range of quality entertainment already available to our customers. We are really excited to be partnering with the BBC to bring BBC iPlayer to our customers."
BT's digital TV service added a modest 30,000 net new subscribers in the first quarter of 2011, bringing its total customer base to 575,000.