Lower corporate tax revenue weighed on the Crown accounts for the three months to the end of September, though the deficit was slightly better than forecast.
Treasury figures released on Wednesday show that the government's operating deficit was $175 million, $400 million better than the $600 million deficit forecast in May.
The operating balance before gains and losses was a deficit of $2 billion, $0.9 billion larger than the $1.1 billion deficit forecast.
Treasury says a $900 million drop in forecast corporate tax revenue was partly to blame, though this was offset to some extent by higher than forecast investment returns from the New Zealand Superannuation Fund and ACC.
The two funds reported returns of $1.4 billion and $0.7 billion respectively.
Gross debt was $48.5 billion - $1.4 billion higher than forecast due to an increase in International Monetary Fund (IMF) reserve liabilities.
