The deal sees the venue renamed as BT Murrayfield Stadium and includes sponsorship of Scotland’s domestic league and cup competitions and the Scotland 7s side from the 2014/15 Series.
It also includes setting up new academies from Scottish Rugby for the development of young talent, with bosses promising to invest back into the game.
The deal follows an earlier tie-up involving sponsorship of Glasgow Warriors and Edinburgh Rugby’s shirts and a multi-year deal to sponsor Arms Park rugby ground, home of the Cardiff Blues, from next season.
Scottish Rugby’s Dominic McKay, said: “In branding our home the BT Murrayfield stadium it reiterates our joint view that the name of the home of Scottish rugby that has been synonymous with the game in our country since 1925 had to be retained.”
“BT is a massive global brand, which we’ve worked with before as sponsor of our domestic league and cup competitions between 1999 and 2006. We also have the pleasure of working with BT Sport, which began its relationship with us at the start of this season, as it sponsors both Glasgow Warriors and Edinburgh Rugby.
“To secure a deal of this nature for the first time in our history means a huge amount for Scottish Rugby, as it will deliver very positively for us for years to come to enable us to continue to invest in our game throughout Scotland.”
John Petter, chief executive, BT Consumer, said: “We’re delighted to be announcing this partnership today, furthering the relationship between BT Sport and Scottish Rugby’s pro-clubs, to support and grow the game in Scotland.”