The channels already show games from Germany’s Bundesliga, France’s Ligue1, Italy’s Serie A and the Scottish Professional Football League.
The Portuguese rights include exclusively live home and away matches played by the league’s ‘Big Three’ teams, current league champions Benfica, Porto FC and Sporting Lisbon.
BT Sport will also have the UK and Ireland rights to show the eagerly-awaited ‘O Classico’ matches between Benfica and Porto.
Grant Best, Senior Channel Executive Producer, said: “We are also delighted to announce today that we’ll be able to offer exclusively live matches from another of the best European leagues, the Primeira Liga.
“Benfica had a hugely successful season last year, dominating domestic competitions, as well as reaching the final of the Europa League. But there are three powerhouses of Portuguese football and Sporting Lisbon and Porto will be looking to catch up this season.
“BT Sport viewers will be able to enjoy the very best matches, including the great O Classico rivalry, and watch some of the stars of the World Cup, including Columbian striker Jackson Martinez, who was top scorer for Porto last season, and the inspirational Sporting Lisbon captain and goalkeeper Rui Patricio.”
BT has also announced the signing of Manchester United and England player Paul Scholes as a pundit on a four year deal.
The ex-midfielder will work on BT’s Barclays Premier League coverage from the start of this season and its UEFA Champions League and UEFA Europa League coverage from the start of the 2015-16 season.