The budget is expected to return an anaemic surplus of $1.5 million at the end of this financial year, revised down from the $36 million surplus predicted in the 2018 budget.

But the March consolidated financial report tabled in the Legislative Assembly on Tuesday revealed the territory's finances are in better than expected shape, with a deficit of $39 million this quarter instead of the predicted $186.3 million.

That's $147 million healthier than expected, largely due to an $82 million decrease in expenses.

About $44.3 million of those savings come back to the delayed commencement of light rail stage one, and uncertainty around stage two.

The Civic to Gungahlin leg of the corridor was finished four months behind schedule, meaning the government saved millions of dollars per month on Canberra Metro's availability payments.

Meanwhile the indecision over which route light rail will take to Woden has meant less has been spent on consultants than expected.

The territory also saved $15.1 million on interest related to the light rail delays, as well as lower than forecast interest on ICON Water Limited related borrowings.

But the budget has also been bolstered by a jump in payroll tax.

The territory government has reaped $419 million in the year to date on payroll tax, $24 million more than expected.

It also made $9.7 million more than expected through goods and services, including an increase in drivers licence and other regulatory service fees.

That increase was also driven by higher than expected water abstraction charges, due to drier conditions, and higher inpatient fees and facility fees driven by growth in health services.

However the territory's net debt has grown to $1.42 billion, an increase of $120.6 million since last June.

The general rates take was $15 million higher than expected, at $559 million, while stamp duty revenue was $16 million lower than expected at $183 million.

Land tax revenue was also slightly lower than expected at $104 million.

The 2019 budget will be handed down on June 4.