The 26 year-old has signed a two-year contract with the French club after his contract with Ulster Rugby was revoked last April.
Christian Lanta, Perpignan's sporting director, said: “Paddy Jackson, in the tradition of Irish 10s, knows how to bring his individual qualities to benefit the collective; a proven kicker, a talented play-maker, Paddy can bring his international experience to the team.”
He will be playing in the Top 14 next season.
Jackson and former Ulster Rugby team mate Stuart Olding, were both fired after a review conducted by the IRFU and Ulster following the Belfast rape trial verdict on 28 March.
