The Government's books remain in the black and are tracking more than $320 million ahead of Treasury forecasts.
The operating balance before gains and losses for the 11 months to the end of May was a surplus of $2.3 billion.
That was $321m ahead of Treasury forecasts released at May's Budget and up from a surplus of $297m for the 10-month period.
A higher than predicted tax take helped drive the difference with core Crown tax revenue coming in at $64.7b - $364m more than anticipated.
The surplus has grown by almost $1.13b compared the same time a year ago.
Crown expenses were close to forecast at $67.2b and have risen 2.3 percent compared to 2015 figures while tax revenue has grown by 5.7 percent from the same period a year ago.