The latest Treasury figures show the ACT's total coronavirus stimulus package has been worth $369 million in new spending and forgone government revenue.

Grattan Institute analysis suggests it is the lowest rate of investment - as a proportion of economic output - of any state or territory.

Canberra Business Chamber chief executive Graham Catt said direct cash support was the missing piece of the puzzle for the ACT.

He noted many businesses had already been struggling to deal with the effects of bushfires and poor air quality in the months before the pandemic hit.

"In NSW and Queensland and some other jurisdictions, there are one-off cash grants available for small businesses," Mr Catt said. "The feedback we get from members, particularly as people start to think about the end of JobKeeper, is that it's that direct cash flow support that is missing.

"There's certainly been waivers of charges or fee deferrals and they've all helped businesses, but what we are hearing is the one thing that would really help the most is that direct cash flow support."

He said the fact some businesses across the NSW border were eligible for grants dealt a blow to the competitiveness of ACT businesses.

"Comparisons among jurisdictions for some small businesses aren't just theoretical, they're actually real and immediate," Mr Catt said.

Chief Minister Andrew Barr said the biggest factor in a lower proportion of economic assistance in the ACT was its level of government employment.

"A far greater proportion of the ACT economy and employment is public sector than any other state or territory," he said.

"As a practical example, the Commonwealth employs one in four Canberrans. They do not pay payroll tax. Therefore ACT payroll tax waivers and deferrals applied to a smaller proportion of the overall workforce. "

Opposition Leader Alistair Coe has accused the government of being "stingy".

"If it wasn't bad enough that the ACT was the last Australian jurisdiction to provide any level of economic support, it's made worse by the fact that the ACT Labor government has also been the stingiest," he said. "While struggling Canberra families and local employers pay the highest taxes and rents in the country, they are getting the least amount of government support in these extraordinarily tough times."

But Mr Barr said the initial phases of the ACT's package had been focused on getting cash out quickly and targeted to those in need.

"Our package was designed to ensure the ACT government was not providing cash assistance on one hand, but then taking it back through fees, charges and taxes," he said.

"We also had to ensure our economic stimulus measures were complementary to the Commonwealth assistance. JobKeeper and JobSeeker payments are supporting those that need it most in our community.

"The ACT government has been focused on minimising other financial burdens on individuals that may be on these payments through rate deferrals and lower ACT government fees and charges."

He said there would be more economic support in the months and years ahead.

Mr Barr also questioned the methodology used by the institute to reach its conclusion, which showed Tasmania's response to be more than 3 per cent of its economic output. The ACT and WA were the only jurisdictions whose response equated to less than 1 per cent of economic output.

Senior ANZ economist Cherelle Murphy said the smaller stimulus package in the ACT reflected the fact that the economy had not suffered as badly as other jurisdictions.

"Certainly, those with public service jobs in the Commonwealth and ACT that live in Canberra are more immune to the COVID-19 lockdowns than others, many being instrumental in getting fiscal stimulus into the economy," she said.

"But as in other states and territories, many of those working in Canberra hospitality, arts and recreation, education and training - especially part-timers - have not been so lucky."