There has been one community case of COVID-19 found in the 24 hours to 8pm on Friday, amid about 25,500 tests across the state.
Returning from holidays, Premier Gladys Berejiklian announced that Saturday would be the final day of lockdown for the northern part of the northern beaches as the cluster the was "in the main under control".
The same restrictions - including the mandatory wearing of masks and visitor and venue restrictions - will stay in place throughout Greater Sydney.
Ms Berejiklian said it was important for the state to keep reassessing its COVID-19 settings, especially as new strains of the virus have been found in overseas travellers returning to Australia.
She said it was vital people kept coming forward for testing in the coming weeks.
Chief Health Officer Dr Kerry Chant said there had been five new cases from overseas found in the 24 hours period.
"We are seeing the emergence worldwide of a number of strains," she said.
"We live in a global world, and all returning travellers are at increasing risk of having one of these mutations."
She said this was a normal part of the evolution of a virus, but said extra safeguards would be put in place to help manage the new strains of the virus.
She said no one would be released from isolation until at least 14 days after their symptom onset, for instance, and people will get tested at the end of their isolation period.
Dr Chant said NSW Health was following up with returned travellers who had the virus.
"We have identified one case that has been tested and does still show remnants of the virus," she said.
"We are taking a precautionary approach by announcing some of the venues that that person attended."
NSW Health last night announced several new venues in Burwood in Sydney's Inner West that have been visited this person including Artisaint Cafe, Bing Lee and Burwood Westfield.
Health minister Brad Hazzard said the increasing number of new variants of the virus appearing in hotel quarantine was a concern.
He said all staff in quarantine hotels would now have daily COVID-19 testing, which would mean there were about 10,500 extra tests in the state. Airline crew will also be tested daily.
NSW Health is treating 110 COVID-19 cases, none of whom are in intensive care. Most cases (99 per cent) are being treated in non-acute, out-of-hospital care, including returned travellers in the Special Health Accommodation.