Sports Illustrated's Peter King broke the story at 4:45 PM EST on Feb. 25th. The text below is directly taken from his article which is linked to on the bottom of the page.
"Tom Brady took a huge step today to ensure he'll retire a Patriot, agreeing to a three-year contract extension that will keep him under center for New England through the 2017 season, when he will be 40 years old.
For the second time in his illustrious career, Brady is doing something players in this day and age simply do not do: As he did in 2005, Brady, a league source told SI.com, is signing a contract with New England that will pay him significantly less money than the market will bear, in large part to help the Patriots stay competitive for the next five seasons.
Amazingly, according to the source, the deal is for an eye-poppingly conservative $27 million, which is less than half his worth by any measure.
The extension will pay Brady a $3 million signing bonus immediately, in addition to salaries of $7 million in 2015, $8 million in 2016 and $9 million in 2017. Brady told Sports Illustrated five years ago he wanted to play until he was 40, at least, and this will accomplish that. He turns 40 on Aug. 3, 2017.
The upshot of the deal is to give the Patriots massive cap relief in a flat-cap era. He was due to count $43.6 million on the New England salary cap in 2013 and 2014. Now, his cap numbers will add up to $28.6 million in the next two years, a savings of $15 million in cap dollars at a time the Patriots have free agents they want to sign to help keep the team atop the AFC East, which they have dominated since Brady took over at quarterback in 2001."