An Australian Institute of Health and Welfare snapshot of the country's hospitals showed the ACT had the lowest proportion of urgent patients who were treated on time; just 50 per cent were seen within 30 minutes.

The report, released on Tuesday, also revealed only 61 per cent of overall patients who presented at emergency departments in the ACT were seen within two hours.

That was the second worst rate in the country, trailed only by the Northern Territory with 57 per cent, and below the national average of 75 per cent.

All patients who arrive at an emergency department are assigned a triage category, with fewer than 1 per cent needing immediate treatment and more than half of patients in 2013-14 assessed as urgent or non-urgent nationally.

Figures showed all resuscitation patients in the ACT were seen immediately but only 53 per cent of semi-urgent patients were seen within an hour.

About 83 per cent of the ACT's emergency patients were seen within 10 minutes, which was above the national rate of 82 per cent.

89 per cent of non-urgent patients were seen within the recommended time of two hours.

Canberra's emergency departments saw 126,000 patients in 2013-14.

The report found 35 per cent of those patients who went on to be admitted had their hospital visit completed within four hours, which was below the national average of 45 per cent.

Western Australia and Queensland had the best proportion of patients seen in four hours or less, both recording 53 per cent, while the Northern Territory had the lowest at 22 per cent.

NSW saw 78 per cent of patients within that time frame, above Victoria's proportion of 69 per cent of patients.

Last year AIHW figures showed the proportion of patients in the ACT whose emergency department visit was completed within four hours was just 59.4 per cent in 2013.

That was below the national average of 70.9 per cent and the worst in the country.

But it was an improvement on 2012, when 56.7 per cent of patients had an emergency department stay of four hours or less.

Tuesday's report also showed 4.7 per cent of the ACT's 12,000 public hospital patients seeking elective surgery waited more than a year, which was above the national average 2.4 per cent.

The ACT recorded the highest average annual increase in emergency presentations of any state or territory, with a 4.2 per cent jump since 2009-10.

That was higher than the national rate of 2.6 per cent.

The figures followed AIHW report from March which showed the number of admissions to ACT public hospitals had increased by nearly 10 per cent during the past five years.

The report found there were 92,019 admissions to the Canberra and Calvary Hospitals during 2013-14, with 18 per cent of recorded presentations involving NSW residents.

It came days after the ACT government revealed a new 140-bed public hospital to be built at the University of Canberra would cost more than $100 million.