New Zealand Post board chairwoman Jane Taylor has resigned two years into a three-year-term.
"I believe the company is in great shape, with a strong strategy to be the best delivery business for New Zealand. I'm very proud of what the company has achieved in the last few years," Taylor said in a statement issued by NZ Post.
NZ Post chief executive David Walsh thanked Taylor for her "substantial contribution to the strategy and direction".
"She's helped guide us to an extremely strong place, locking in the strategy that everyone is now working so hard to deliver on," he said in a statement.
"Jane has decided to resign from the NZ Post board, and I have accepted her resignation," Finance Minister Grant Robertson said.
"We'd like to thank Jane for her significant work in setting up NZ Post's strategy, and guiding the organisation through a significant period of change," he said.
Robertson later told reporters Taylor, who was appointed by the previous National government in 2016, had resigned over matters internal to the New Zealand Post board. He did not elaborate.
"Ms Taylor was appointed for a three-year term. Clearly it's earlier than that. But those really are matters internal to the Post board," he said.