Jackson missed the first 12 days of training camp in search of a new contract, as he was entering the final season of his rookie deal in 2011.
The California product eventually posted 58 receptions for 961 yards and four touchdowns over 15 games last season, adding 18 punt/kick returns for 121 yards.
"We will continue our efforts on getting a long-term deal done with him," said Birds general manager Howie Roseman shortly after the announcement.
Under NFL rules, Jackson is set to make the average salary of the top five players at the position, -- which has been reported as high as $9 million -- a hefty increase from his initial contract.
Jackson is the Eagles' all-time leader in punt return touchdowns with four, and in 2009 tied an NFL record with eight touchdowns of at least 50 yards.
He has compiled 230 catches for 4,096 yards and 21 scores over 60 games, with 1,226 punt return yards on 116 attempts.