The ACT collected nearly half a billion dollars in rates last quarter, as it recorded a higher-than-expected surplus.
The territory's headline net operating balance was $369.7 million in the three months to September, about $40 million higher than expected, the latest consolidated financial report has revealed.
The unexpected windfall came as a result of lower expenses, because of the timing of payments for capital projects.
Analysis showed the territory government received 61 per cent more rates in the last quarter than it did in the same quarter five years ago, rising from $297 million to $480 million.
In contrast, stamp duty fell by 7 per cent in the same period to $70 million.
This is part of the ACT's shift away from stamp duty in favour of a land-based taxation system.
However the government received about $1.8 million more in general rates than forecast and about $4 million more in stamp duty.
The government copped widespread criticism after homeowners were hit with average rates rises of 7 per cent.
In August, financial reports revealed ACT Chief Minister and Treasurer Andrew Barr delivered a balanced budget for 2016-17, the first in five years.
The June quarter saw a deficit of $10.6 million, which was a big improvement on the $74 million deficit forecast at budget time in June.