Finance Minister Grant Robertson is about to reveal the priorities for his first Budget.
His Budget Policy Statement will show the cost of the Government's spending promises and indicate how they'll be met.
At the same time, the Treasury will release its half-year economic and fiscal update (HYEFU).
HYEFU shows the latest projections for economic growth in coming years and the state of the Government's books.
The cost of the Government's 100-day plan will be included.
Details of the Families Package, a flagship policy and a key budget issue, will also be released.
Legislation to implement the Families Package is expected to be introduced to parliament on Thursday afternoon.
- Jacinda Ardern commits to 100-day plan, with one exception
- Jacinda Ardern commits to extending paid parental leave
The Budget Policy Statement and the HYEFU will be released around 1pm.