Record low bulk billing rates among ACT doctors has been cited along with an ageing population with increasingly complex conditions and the hospital's role as the region's main trauma centre for the region, as the key reasons behind the rising pressure on the ED.

The latest health performance report shows the demand on the emergency departments at both Canberra Hospital and Calvary Public Hospital in Bruce continued to rise to July this year, with presentations to the two EDs increasing from 125,737 in 2013-14 to 135,307 in 2015-16.

The Canberra Times has previously reported the out-of-pocket cost of seeing a doctor in the national capital had doubled over the past decade to more than $40, while bulk billing rates had risen only only 6.3 per cent over the same period.

The health department's annual report tabled in the ACT Legislative Assembly last week does not clarify whether the low bulk billing rates had increased the number of people going to the ED during daylight hours or at night.

An ACT Health spokeswoman said that while primary health care was led by the Commonwealth, the ACT had "comparatively low numbers of bulk-billing GPs and that "we would like to see this increase because this can have flow on effects for other health services, such as the ACT emergency departments".

"Low rates of bulk billing mean more people are having to pay to access a GP and Cost is a factor that can cause a person to delay or even avoid accessing a GP," she said.

"We know that when people delay care, they often will later need more higher cost services such as the ED."

Australian Salaried Medical Officers' Federation ACT branch secretary Stephen Crook said the low bulk billing rate, and the pressure of patients presenting at the ED instead of seeing a GP, was a common concern among doctors working at Canberra Hospital.

But he said it depended on "what you define as bulk billing" and he believed there were two factors driving the increasing pressure.

"If you talk about people not going to a GP surgery, that's one factor," he said.

"But the second factor is outpatient visits at the hospital and I understand some people have been reluctant to use their Medicare cards and ensure they have the appropriate referrals," he said.

"It's in everybody's interest that where possible the commonwealth is bulk billed for service, rather than those bills being a drain on state or territory's limited available resources."

Mr Crook said the environment in the hospital's ED, as a result of increasing pressure across the board, had become "very, very challenging", and that changes including the Medicare rebate freeze and funding cuts at the federal level, were also "compounding factors" putting more financial pressure on the ACT's health system.

Despite the low bulk-billing rate, she said the ACT Government had invested $12 million in incentives to support the GP workforce, supported two practices helping vulnerable communities and established two nurse-led walk-in centres, while three more were promised at the election.

While wide-ranging reforms are also underway to the ACT's health system, the spokeswoman said the $23 million expansion of the hospital's ED had increased capacity by 30 per cent, an expansion due to be completed by year's end.

Comment was sought from the AMA ACT before filing.