The agency won the business after a three-way pitch process that was called by the dating company in July. Karmarama will also work on Eharmony’s advertising in Australia.
St Luke’s has previously worked on the UK business, overseeing the brand’s launch into the UK in 2007. However, recent UK campaigns were handled by the brand’s US agency DonatWald+Haque.
Karmarama’s appointment follows the hiring of Ottokar Rosenberger as eHarmony’s UK country manager in January. Since then, eHarmony has also appointed PHD as its media agency.
Recent advertising from eHarmony, which claims to have more than 1.5 million registered UK users, featured a selection of eHarmony members talking directly to camera about their motivations for using the service.
Rosenberger said: "We have had incredibly successful launches into the UK and Australia and we are now looking to grow our presence as the only significant compatibility based matchmaking service in both markets.