On August 15, 2017, Davis signed a one-year contract extension with the Panthers through the 2018 season. On November 3, Davis was fined $48,620 for a helmet-to-helmet hit on Adam Humphries in Week 8 against the Tampa Bay Buccaneers. On December 18, 2017, Davis was suspended two games after an illegal helmet-to-helmet hit to Packers wide receiver Davante Adams which caused a concussion. The next day, his suspension was reduced to one game after an appeal. He finished the season with 76 combined tackles and 2.5 sacks, on his way to his third straight Pro Bowl. He was ranked 73rd by his peers on the NFL Top 100 Players of 2018.