ACT's daily COVID-19 cases have reached a new record, with 85 new infections reported on Thursday.
The previous high was 58 daily cases which was recorded on Wednesday.
The large spike in infections comes as health authorities in Canberra move to change contact tracing measures and reintroduce restrictions for hospital visitors.
Visitors will be barred from seeing patients in ACT hospitals from Boxing Day, except for end-of-life care, birthing, or pediatric situations.
The current rules, a maximum of two visitors per patient per day, will remain in effect through Christmas.
While COVID-19 case numbers have gone dramatically up, hospitalisations remain stable.
There are three COVID patients being treated in Canberra hospitals, with none of those being in intensive care or on a ventilator.
Ahead of Christmas, testing clinics across Canberra have been overwhelmed with demand with people forced to wait for several hours.
All of the ACT's four main testing clinics were at capacity early on Thursday, with many Canberrans needing tests to travel interstate.
There were 7067 tests conducted in the ACT on Wednesday, the fourth-highest daily amount since the pandemic began.
Despite the testing surge, Health Minister Rachel Stephen-Smith said turnaround times for people to receive test results had not been impacted.
"People are doing a good job at coming forward," she said on Thursday.
Ms Stephen-Smith mentioned there was no hard data for the number of people getting tested just to travel interstate, but said anecdotal evidence pointed to a 50-50 split.
The health minister said despite the surge for testing, more sites would not be established due to staffing levels.
"We didn't have staff to stand up those extra locations, and we would get a more efficient use of staff if we put them into sites we've already got," Ms Stephen-Smith said.
As case numbers increase, ACT chief health officer Dr Kerryn Coleman said contact tracing measures would be changed.
Close contacts will now only be defined as a household contact of a positive case, or someone who has spent an extended period of time with a positive case.
Casual contacts will no longer need to fill out a declaration form for ACT health authorities, but will still need to get tested and isolate until a negative result is received.
"This bring us into line with how NSW and Victoria are assessing close contacts and it means we are all identifying those who become cases," Dr Coleman said.
"We won't be collecting as much information from cases... the focus is on high-impact sites where it's likely transmission has taken place."
Dr Coleman said she was concerned about large-scale events coming up in Canberra, including New Year's Eve fireworks and the annual car festival Summernats, due to coronavirus transmission risk.
However, she said there were COVID-safe measures in place to help prevent them becoming superspreader events and was assured by the efforts of organisers.