The government has recorded a unexpected budget surplus in the eight months to the end of February.
The operating balance before gains and losses showed a surplus of $398 million for that period, when it had been forecasting a deficit.
The current surplus compares with a deficit of $269 million at the same time last year.
Core Crown tax revenue has increased by 5.3 percent while core Crown expenses have grown by 3 percent over that time.
Net debt was lower than forecast at $62.4 billion.