Neil Brettell, commercial director of Allianz Personal said: "I am tremendously excited about working with Joshua G2 as we look for ways to grow our direct business in what is a very challenging and fast moving environment.
The other short listed agencies were Archibald Ingall Stretton, Draftfcb and Tullo Marshall Warren.
Allianz does not retain a below-the-line agency.
The German insurer has previously worked with the now-defunct WWAV Rapp Collins Leeds, and the Direct Agency, which handled the group's Premierline Direct and Pet Plan brands respectively.
The pitch was overseen by the Observatory.