The cost of holding two referendums and consulting on a change of flag has been estimated to be just under $26 million.
Cabinet has now agreed on the details of the flag referendum process with every political party invited to take part.
Along with the costing it has also been announced that Finance Minister Bill English will be the Minister responsible for the flag consultation process.
All political parties have been written to asking them to nominate an MP to be part of a cross party group on the flag change process.
The Government wants to hold two votes on whether to change the flag, the first next year will invite the public to choose a preferred new design.
The winner of that vote will then go into a run off with the current flag in 2016.