Pertteli (Swedish: S:t Bertils) is a former municipality of Finland, located in the Southwest Finland region. It was consolidated with the town of Salo on January 1, 2009, and since then has formed part of Salo rather than existing as an independent municipality.
Before the merger, Pertteli bordered the municipalities of Kiikala, Kisko, Kuusjoki, Muurla and Salo. Its administrative status as a separate municipality ended with the 2009 consolidation.