NSW Premier Gladys Berejiklian has warned the state to "brace ourselves" for locally acquired coronavirus cases as Brisbane enters a snap three-day lockdown.
Queensland's outbreak grew by eight local cases on Tuesday, five of which visited NSW's holiday hotspot Byron Bay on the weekend.
They are linked to two previously identified cases, a nurse and her sister, who were with the five cases in Byron for a hen's party.
"We hope that we do not have any cases arise in New South Wales but I would not be surprised if we did, so we must brace ourselves," Ms Berejiklian told reporters.
While other states have slammed their border shut to Queensland, Ms Berejiklian, who has previously pushed against the need to close state borders, once again said there was no need to do so at this stage.
However she said authorities will "have to respond" if a significant number of cases emerge in the state.
Anyone who has entered NSW from Queensland since March 20 must isolate for three days, however can leave the home for essential reasons that include shopping for food and supplies, exercise and essential work where it is not practicable to work from home, NSW Health said.
"And most importantly, if you've attended any of the venues NSW Health has identified, get tested, stay home and isolate for the full 14 days," the premier said.
Infected travellers visited the Byron Beach Hotel, the Mokha Cafe, The Farm at Ewingsdale the Suffolk Beachfront Holiday Park public toilets between March 26 and 28.
NSW has not recorded a local case of coronavirus since a security guard contracted the virus at the Sofitel quarantine facility in Sydney's CBD. The state had gone 55 days without a case prior to the leak.
Do you have a story tip? Email: firstname.lastname@example.org