Rotherham were keen on keeping the 22 year-old whose consistent displays in 31 loan appearances took the club to Wembley in the play-offs.
Tavernier made nine senior appearances for Newcastle including Europa League starts against Atromitos, Bruges and Bordeaux, but his only two Barclays Premier League matches came in two outings as a substitute the season before last.
He had loan spells at Gateshead, Carlisle, Sheffield Wednesday, MK Dons and Shrewsbury as well as Rotherham.