Pouncey was in the final season of a two-year, $15 million contract. The extension will be worth $9 million next season.
General manager Tom Telesco said in a statement that Pouncey has become one of the unquestioned leaders of the team.
Pouncey earned his fourth Pro Bowl selection last season after starting all 18 games, including the playoffs. He was credited with allowing only a half sack, the best mark of his career. Pouncey signed with the Chargers after spending seven seasons with the Miami Dolphins, who drafted him with the 15th overall pick in 2011.
More AP NFL: https://apnews.com/NFL and https://twitter.com/AP-NFL