National list MP Paul Foster-Bell will quit Parliament at this year's election.
Mr Foster-Bell said he had told party members in the Wellington Central electorate he would not be putting his name forward to contest the seat, and he would not be seeking a place on the list.
A former diplomat, Mr Foster-Bell first entered parliament in 2013.
He stood in Wellington Central for National in 2014, but lost against Labour's Grant Robertson.
Mr Foster-Bell said it had been an honour to be an MP, but it was the right time for him to pursue other opportunities.