It will also safeguard the employment of 187 BT people who are being retrained to work for BT Sport customer support.
The communications giant said it was taking over ESPN's channels in the UK and Ireland in a buyout which will allow it to show 30 games from the Scottish Premier League (SPL) a year plus 10 Rangers games.
ESPN signed a joint £80 million deal along with Sky TV for the rights to Scottish football last year, with ESPN's contribution thought to be around £4m a season.
However, the broadcaster suffered a change of heart and is understood to have been keen to get out of football after losing the rights to show matches from the English Premier League.
BT, which has diversified away from its traditional model as a phone landline provider over the past decade, has committed to broadcast games until at least 2017.
As well as the Clydesdale Bank Scottish Premier League, the deal will enable BT Sport customers to see live coverage of the FA Cup for the 2013/14 season, the UEFA Europa League and German Bundesliga through to the end of the 2014/15 season.
BT Sport will also show 38 live Barclays Premier League matches on TV, including 18 of the top pick games previously only shown on Sky.
BT Sport's football coverage will be fronted by Jake Humphrey. In addition, BT has signed a deal with the Women's Tennis Association (WTA) to show up to 800 hours of live tennis, including the TEB BNP WTA Championships.
Jake will be joined by Clare Balding, who will host a sports magazine show, and former rugby player and TV commentator Lawrence Dallaglio.
The new BT Sport contact centre, officially opened by Dallaglio, is based in Accrington, Lancashire, creating 75 more jobs in the area.
More than 300 further new sales jobs will be created for BT Sport at BT’s contact centres in Canterbury, Doncaster, Truro, Warrington, Newcastle, Glasgow and Dundee.
The initial launch phase will also create a further 400 short term sales opportunities for the first six months.
Gavin Patterson, chief executive of BT Retail, said: “BT Sport is an important new chapter for us and it also promises to give a boost to the UK economy by creating hundreds of new job opportunities across the UK.
“BT Sport is about giving people more choice about what they watch, where they watch it and how much they pay.”
The BT Sport channels will be based at the iCITY development at the Queen Elizabeth Park in Stratford, London.