The Niners and Kittle agreed to a five-year, $75 million contract on Thursday, league sources confirmed to ESPN.
The deal was first reported by Barstool Sports, which reports Kittle received $40 million guaranteed for injury and $30 million guaranteed at signing.
The deal, which had been expected for most of the offseason, easily surpasses the four-year, $42 million contract Austin Hooper signed with the Cleveland Browns in March and the average annual value is slightly more than the four-year, $57.25 million extension given to Chiefs tight end Travis Kelce later Thursday afternoon.
Kittle and Kelce are widely considered the NFL's top players at the position.
"It is a cool thing when you're talking about a big deal for somebody, especially in the uncertain times that it is now with the salary cap changing and whatever the revenue differences are going to be this year," coach Kyle Shanahan told KNBR radio in San Francisco on Thursday. "... It's not about just being the best tight end in the NFL, it's who he is after that. That to me makes me want to get this stuff done when you might not actually have to right now. And especially for a guy like that.
"He's earned it. He does everything the right way. It starts with how talented and good you play on Sunday. As I just said, he does that to me better than any tight end in the league. But then after that, the way the guy takes care of himself, the way he works year round to put his body in a position to stay healthy with the way he plays, it makes you believe in the guy. It makes you believe in not only what he has done but what he's going to do. When you have a guy like that, I think it makes it a lot easier for the owner to commit to him like that."
The Niners and Kittle went through a lengthy contract negotiation, which began after the Super Bowl and was complicated by the coronavirus pandemic. The potential for a revenue shortfall from playing games with no fans in the stands -- and an ensuing salary-cap drop -- created uncertainty about how to structure a potential deal.
Kittle reported to training camp and participated in all team activities without so much as a threat of a holdout. Because the sides remained amicable throughout the process, general manager John Lynch and Shanahan remained optimistic that a deal would get done as the Niners opened camp.
"We've been real excited about it," Shanahan told KNBR. "Something we've been working on for a while. Both sides wanted to get a deal done so usually it happens. But it's always a tough deal to work through all that. We finally got it done. Pretty nice, especially right before we're about to put on pads and get to practicing here in a couple days."
This summer, NFL players ranked Kittle as the seventh-best player in the league, regardless of position. He has racked up 2,945 receiving yards -- the most by any tight end in NFL history after three seasons, surpassing Mike Ditka and Rob Gronkowski. In 2018, Kittle set the record for most receiving yards in a season by a tight end when he finished with 1,377.
Over the past two seasons, Kittle ranks sixth in the NFL among all pass-catchers with 2,430 receiving yards, 11th with 173 receptions and second with 1,464 yards after the catch.
Beyond his receiving prowess, Kittle is widely regarded as one of the best blocking tight ends in the league. In two games without him in 2019, the 49ers averaged 2.63 yards per carry and 60.5 rushing yards with no touchdowns on the ground. In the 14 games he played, the Niners averaged 4.83 yards per carry and 156 rushing yards per game with 23 rushing touchdowns.
All of that earned Kittle a Pro Bowl nod in each of the past two seasons, a second-team All-Pro spot in 2018 and a first-team All-Pro spot in 2019.