The midfielder signed a deal until 2030 with Benfica and joins for an initial €14 million, with five more to be paid in potential bonuses.
"The 31-year-old Portugal international is returning to his home city of Lisbon, where he began his professional career at Sporting," said Bayern in a statement.
Benfica said the midfielder had a €50 million release clause in his deal.
Bayern signed Palhinha from Fulham in 2024, and he won the Bundesliga with the German giants in 2025, before being loaned to Tottenham last season.
The midfielder had been linked to Premier League side Aston Villa earlier this summer.
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