The 27-year-old rake has re-signed with New Zealand Rugby (NZR) and the Highlanders for two more years, joining team mate Ben Smith in re-committing to the Dunedin-based team this year.
The Highlanders confirmed Coltman, who made his test debut during the All Blacks' 68-10 win against Italy in Rome last November, opted to extend his time with the team via social media on Tuesday.
"I absolutely love Dunedin, love the place, can't get enough of it," Coltman said in a video posted by the team.