National's Erica Stanford will pick up responsibility for the previously unallocated Royal Commission of Inquiry into Abuse in Care. She is already minister for Education and Immigration.
ACT leader David Seymour will become Associate Justice Minister with responsibility for the Treaty Principles Bill. He retains his other Minister for Regulation and Associate Minister for Finance, Health (Pharmac), and Education (Partnership schools) roles.
NZ First MP Mark Patterson adds Associate Regional Development to his Rural Communities and Associate Agriculture roles.
NZ First's Jenny Marcroft, who is Parliamentary undersecretary for Media and Communications, will now also be Parliamentary Secretary for Oceans and Fisheries.
Luxon said the reshuffle "further clarifies ministers' responsibilities in a small number of areas, supporting them in continuing to deliver on this government's ambitious work programme".
"Ministers have hit the ground running since they were sworn in nearly two months ago with strong progress made on the coalition government's 100-day plan," he said.
None of the new positions affect membership of Cabinet or the size of the executive.
