OPINION: If prime minister-elect Jacinda Ardern is about to put her stamp on her Cabinet it will have to come from some very surprising portfolio allocations.

Because the list of 21 ministers elected by the party's caucus on Friday is about as predictable as checking the party's existing line-up.

There were 16 posts inside Cabinet on offer, and five outside, after allowing for the seven to be shared between NZ First and the Greens.

Hannah Peters

Prime minister-elect Jacinda Ardern and finance minister in waiting Grant Robertson at her house the day after the election.

But the only name missing from the pre-election shadow cabinet is Te Tai Hauāuru MP Adrian Rurawhe, who will likely pick up the Maori Affairs select committee chair and be promoted to chief whip.

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Ardern has signalled her interest in continuing the traditional role of the prime minister, overseeing intelligence and security, and she has a strong interest in the children's portfolio and arts - although on the campaign trail she mooted the need for associates in some of those areas to lighten the load.

Grant Robertson as finance minister is a given and David Parker is likely to retain attorney general, as one of the few lawyers in the Labour line-up.

Nanaia Mahuta is in line for Maori development, relieving deputy leader Kelvin Davis who is likely to be given corrections but pick up other portfolios, perhaps tourism.

But many of the roles are still up in the air, pending decisions on Green and NZ First's portfolios - including whether Winston Peters will be confirmed as deputy prime minister and/or accepts the foreign affairs job. NZ First is also set to take on the heavy lifting in the economic and regional development areas as well as transport and infrastructure.

The Greens would seem to have the inside running on climate change and conservation, as well as at least one important social policy portfolio.

Chris Hipkins is the logical leader of the house, and has made the education role his own so will likely keep it. But NZ First's Tracey Martin would make a logical associate alongside her main responsibilities.

David Clark is the incumbent in the health area and there are no clear signs of him losing that.

But it seems there is no room for new talent, such as New Lynn MP and tax expert Deborah Russell, as Ardern continues John Key's approach of not promoting tyro MPs.

The 16 Labour Cabinet ministers are; Jacinda Ardern, David Clark, Clare Curran, Kelvin Davis, Chris Hipkins, Iain Lees-Galloway, Andrew Little, Nanaia Mahuta, Stuart Nash, Damien O'Connor, David Parker, Grant Robertson, Jenny Salesa, Carmel Sepuloni, Phil Twyford and Megan Woods.

The five ministers outside Cabinet from Labour are - Kris Faafoi, Peeni Henare, Willie Jackson, Aupito William Sio and Meka Whaitiri.

Four cabinet positions will go to NZ First as part of the coalition deal, exp[ected to be Peters, Ron Mark (favoured for defence minister), Martin and Shane Jones. The Greens will have three ministers outside of Cabinet, likely to go to leader James Shaw, Julie Anne Genter and Eugenie Sage. 

There will also be two under secretaries, one each for NZ First and the Greens.

 - Stuff