NSW has recorded 18 new COVID-19 cases, taking the total to 130 since the Bondi cluster emerged earlier this month.
Fifteen of the new cases are directly linked to the Bondi cluster, which started on June 16 and now tallies 124.
Two cases are close contacts of a previously reported unlinked case, and the last may have been acquired at Westfield Bondi Junction.
Around six of the new cases were in isolation for the entire time they were infectious and more were isolated for some of their infectious period.
But "some, unfortunately, were active in the community", NSW Premier Gladys Berejiklian said on Monday.
Some 58,870 people were tested in the 24 hours to 8pm on Sunday, up from 52,048 the previous day.
Ms Berejiklian and Chief Health Officer Kerry Chant warned the public against taking a sigh of relief at the numbers, despite being considerably lower than the previous day's total of 30 locally acquired cases.
"We have to be prepared for the numbers to bounce around and we have to be prepared for the numbers to go up considerably," Ms Berejiklian said.
Dr Chant said the numbers were not expected to decline for at least another five days.
She said the real relief would come when all new cases are linked and already in isolation.