BT will start charging for BT Sport from this summer. From 1st August, BT TV customers will have to pay £3.50 a month for BT Sport channels, with an annual subscription costing £42.
If you watch through a Sky box, you'll have to pay an extra £1 each month starting in April, bringing the total cost to £22.99.
Those who watch through a Sky box but who have BT broadband will also see the cost of BT Sport rise. It will go up by £1.50 each month, bringing the total price to £7.50.
At the moment, BT Sport is free for BT TV customers who have BT Broadband.
The move comes as part of a price rise for broadband and landline calls. These will kick in from April.
BT claimed that its service would improve at the same time as the price rises.
"Customers will get a better package and improved services from us this year in exchange for paying a little more," said John Petter, chief executive of BT Consumer.
"Millions will have the chance to upgrade to faster broadband and almost a million will be able to upgrade to enjoy unlimited usage for no extra cost."
BT Sport has proved a real rival to Sky Sports since it burst onto the scene. While Sky still has the lion's share of the broadcast rights to Premier League football matches, BT has exclusive rights to the UEFA Champions League. It also launched Europe's first 4K sports channel in the form of BT Sport Ultra HD.