Filming will begin on the eight-part third series later this year. The fourth series of a further eight one-hour episodes is due to be shot in 2006.
It's the first time that more than one series of a drama has been re-commissioned at the same time, but it could be the sign of things to come.
Jane Tranter, Controller, Drama Commissioning, BBC says: "Double commissioning is designed to allow independent production companies the creative freedom to think further forward with their development of long running drama for the BBC.New Tricks is made for the BBC by Wall to Wall television. It was created by Roy Mitchell and Nigel McCrery, and writers on the current series are Roy Mitchell, Nick Fisher, Karen Maclachlan, Howard Overman and Danny Miller.
"This is a clear commitment from us to continuing to secure the very best drama for our audience, and another way of making BBC commissioning more nimble."