BT is streaming the Champions League and Europa League finals for free on YouTube
The games can also be watched on Freeview channel 59, BT.com and BTSport.com.
The Europa league final - between Liverpool and Sevilla - takes place on Wednesday May 18, while the Champions League final - between Real Madrid and Atletico Madrid - is set for Sunday May 28.
Gary Lineker, who usually presents BBC football, will be joining the BT team for their Champions League coverage from the San Siro stadium in Milan.
The move comes after disappointing viewing figures of Champions League and Europe League on BT. The company paid £900 million ($1.3 billion) for the rights to broadcast Champions League games from the 2015/16 season onwards for three years. The games were previously on ITV.
But the shift to pay-TV service BT Sport resulted in a significant drop in ratings - from 4.4 million on ITV to just 200,000 at point. A BT spokesman said last year that: "BT and is very happy with its ongoing coverage and excellent production of the UEFA Champions League."
Christoph Pleitgen, an executive at video platform Wochit, says in an emailed statement that BT "has gotten very little value for money to date."
He adds: "In light of this performance, today's announcement of its plans to stream on YouTube two finals from European football's premier club tournaments is not surprising in the least. YouTube is a perfect outlet for BT Sport to attempt to maximise its audience, while also attracting the highest paying sponsors."
John Petter, chief executive of BT Consumer, said BT was trying to bring a sense of community to the broadcast: "We plan to make these finals the most social sports broadcast ever, with lots of exciting content in the build-up and on the night across YouTube, Snapchat, Facebook, Instagram, Twitter and Vine."
He added that this method of coverage could become the norm for other sporting competitions:
BT Sport has pioneered the way when it comes to new technologies and digital platforms, whether that's live Ultra HD, our immersive BT Sport App or red button functionality on YouView. Today's announcements will take this further, and there's plenty more that we're looking at, whether that's more programming in live Ultra HD, new App developments or our recent Virtual Reality trials at the FA Cup semi-finals and NBA.
BT's decision to stream the matches online is the latest shift of sports online. In April, Twitter won the rights to stream NFL Thursday night games in the US on the microblogging platform.