Senderos seals Everton switch
The 24-year-old, who has been capped 35 times by his country, spent all of last season on loan at Italian side AC Milan after falling out of favour with coach Arsene Wenger.
A 2005 FA Cup winner, the imposing centre-back has made a total of 117 appearances for the north London club since joining from Swiss side FC Servette in June 2003.
He leaves second-placed Arsenal for David Moyes' Everton side currently 10th in the table, seven points off the relegation zone.
"Everyone at Arsenal Football Club wishes Philippe the best of luck during his time with Everton," a statement on the club website said.