Watson has led BT TV since 2009 and is said to have been “central” to the firm’s successful move into sports broadcasting.
The service has “more than” 950,000 subscribers, making it the UK’s third biggest pay-TV platform behind Sky and Virgin Media.
In a statement, Watson said “I have had a fantastic time at BT, enjoying many years in an amazingly fast and dynamic marketplace. I’m sad to leave but now is the right time for me to take on a fresh challenge.
“I am proud of what we have achieved in BT TV. We have built a top quality TV service from scratch and BT Sport is thriving thanks to the great live sport we’ve secured. I am sure the business will go from strength to strength and I wish everyone at BT well.”
John Petter, BT Consumer Chief Executive praised Watson saying “I would like to thank Marc for helping us bring BT TV to a large audience and for helping us to launch BT Sport with the very best live sporting action including top tier football, rugby, tennis and MotoGP rights. He leaves with our best wishes for the future”.
BT says the search for a new Managing Director of BT TV & Sport “is well underway” with both external and internal candidates being considered.