BT has acquired three million direct BT Sport customers, including those watching via satellite, BT TV, online or via the app.
Since launching in August 2013, the subscription sport service has gone from strength to strength, and viewing figures continue to rise.
In total, with BT's wholesale deals with other TV providers included, BT Sport is now available in five million UK households.
Subscribers are able to enjoy a host of top sporting action, including Barclays Premier League football, Aviva Premiership rugby union, NBA basketball, WTA tennis, UFC and Moto GP.
Gavin Patterson, Chief Executive at BT, said the sports platform "has proved very popular" since its launch last year.
"We are delighted the service is now in around five million homes," he stated.
"For BT Consumer it underpinned a record nine per cent growth in revenue in the fourth quarter and the lowest line losses in over five years," Mr Patterson stated.
BT recently announced that its own broadband customers will be able to enjoy free access to BT Sport for a second season.
Subscribers who have BT TV can watch the action on BT Sport 1, BT Sport 2 and ESPN on their television sets at no extra charge.
All other BT broadband customers have access to the channels over the internet or via the BT Sport app.
John Petter, BT Consumer Chief Executive, claimed that "fans have been the winner" with BT Sport.
"Millions of homes have enjoyed the very best sporting action for free. We said we would shake up the market and we have done just that," he stated.
"There has never been a better time to switch to BT broadband so I would encourage sports fans to sign up."