PREFU 2026: What to Expect When Treasury Opens the Books

Treasury will release the Pre-election Economic and Fiscal Update (PREFU) 2026 at 1pm NZT on 29 September 2026.

The PREFU is prepared by Treasury, not the Government. It is an independent stocktake of the books, and parties use it as the baseline for costing campaign promises, according to RNZ. The release date is listed by Treasury.

The starting point is the May Budget update. It forecast a return to surplus in 2028/29, a year earlier than previously forecast. A surplus means the Government collects more in tax than it spends. A deficit means it spends more than it collects and must borrow to fill the gap. The Government forecast a deficit of NZ$15.06 billion for the year to 30 June 2026, according to Reuters. Treasury forecasts reported in May pointed to a deeper deficit and weaker growth heading into the election.

The latest Crown accounts showed expenses down and tax revenue up. Economists at Westpac, ANZ and ASB expect the near-term fiscal position to be slightly stronger.

Westpac expects the PREFU to be broadly similar to Budget 2026, with a slightly more favourable near term. RNZ reported the PREFU could point to slightly less borrowing this year and a smaller deficit. Most economists expect no change to Treasury's Budget forecast of a return to surplus in 2028/29.

The picture for later years is less certain. ASB says higher interest rates, higher oil prices and lower population growth from lower immigration could lead Treasury to lower its economic and fiscal projections further out. ANZ warned the medium-term forecasts were at risk of a downgrade, saying the May Budget forecasts were optimistic and interest rates have risen since then.

Treasury's economic forecasts for PREFU 2026 were likely finalised in mid- to late August 2026, according to BusinessDesk. That locks in assumptions before late-September data and detailed campaign policy costings.

Finance Minister Nicola Willis suggested in a weekend campaign speech that people will like what they see at the PREFU. Labour said it will release detailed fiscal plans only after the PREFU is published.

Treasury has revised its forecasts before. In November 2024, it said it would likely cut its economic and fiscal forecasts because of a sustained slowdown in productivity. In September 2023, it expected a return to surplus by 2026/27, one year later than previously planned.

The broader context here is the split between near-term cash flow and the path back to surplus. A smaller deficit this year would let the Government argue its fiscal management is working. It would not by itself change the surplus date. That date turns on Treasury's calls on productivity, population growth from migration, oil prices and interest rates. The near-term borrowing and deficit lines will shape daily campaign messaging, while the medium-term assumptions will carry more weight for spending allowances, the debt track and whether promises stack up from this baseline.