Spikes, who is a two-time Pro Bowl player, represented the Chargers for two seasons and started 16 games in each of his two years at the franchise.
"Takeo is a true professional and a class act," Chargers general manager Tom Telesco said in a statement.
"We're grateful for his many contributions to the Chargers organisation, both on and off the field, and wish him nothing but the best in the future."
Spikes himself was grateful for the opportunity he was given by the Chargers.
On Twitter, he said: "Thank you to the @chargers, Spanos family and fans for the opportunity to represent the organisation. I look forward to this upcoming season."
It is not yet known if there has been any interest from other franchises to sign Spikes for next season.