The extension includes a $12 million signing bonus with an average annual salary of $7.5 million, according to Olsen's agent, Drew Rosenhaus.
Olsen tweeted a photo of himself signing the contract:
Im blessed to announce Ive signed a 3yr extension! I'm honored to call this home pic.twitter.com/9KQBwNMLKk— Greg Olsen (@gregolsen88) March 5, 2015
He is entering the final year of a five-year deal with Carolina with a 2015 salary-cap figure of $7.8 million. The new deal runs through the 2018 season.
"We are very pleased and excited to have Greg on board for the next four years,'' general manager Dave Gettleman said in a statement. "He is a professional in every sense of the word. Greg's leadership and work ethic is a great example for our young guys.''
Olsen made his first Pro Bowl last season after setting team single-season records for receptions (84) and receiving yards (1,008) by a tight end. He was third among all tight ends in receptions, second in yards and tied for seventh with six touchdowns. The six touchdowns made him the only NFL tight end with five or more touchdowns in every season since 2008.
The Panthers acquired Olsen at the start of training camp in 2011 in a trade with Chicago, which received a 2012 third-round pick. Olsen was a first-round pick (31st overall) by the Bears in 2007.
Olsen tweeted his thanks to the Panthers for the extension:
Thanks Mr Richardson, Mr Gettleman, Coach Rivera & the entire organization. Thankful for my coaches and teammates. Couldnt be more thankful— Greg Olsen (@gregolsen88) March 5, 2015