Wiggins posted the news on his Instagram account.
Wiggins was originally designated a restricted free agent, but the Chargers declined to tender the Fresno State product, making him an unrestricted free agent.
Wiggins, 28, played 129 snaps on offense in 2016, including one start against the Miami Dolphins. For his career, Wiggins has played in 29 games with nine starts in three NFL seasons.
With Wiggins in the fold, the Chargers now have 12 offensive linemen under contract as they build the 90-man roster for the opening of training camp at the end of July.