There have now been 48,061 locally acquired cases and 255 deaths reported since the start of the Delta outbreak.
There are currently 1,266 COVID-19 patients in hospital in NSW, with 244 in intensive care units and 118 requiring ventilators.
The new lockdown in the state's north comes after local COVID-19 cases were uncovered.
Tweed Heads, Byron Bay and Kempsey to re-enter lockdown
NSW Health Minister Brad Hazzard said the case in Byron Bay was brought in by an essential worker who travelled to the area from Sydney for work.
He called for residents to come forward for testing in large numbers.
"So far, those areas have been kept relatively safe but we need the community to keep getting tested so that the public health team can be very, very certain of what we need to do at the expiration of those seven days," Mr Hazzard said.
There was also a positive case in Tamworth, but stay-at-home orders are still under consideration because the person was not active in the community.
NSW's vaccination goals remain on track, with 82.5 per cent of eligible people vaccinated with one dose and 53 per cent with two.
Friends bubble for under-18s
Meanwhile, there's some much-needed respite for parents with younger children, with a 'friends bubble' kicking in at noon Tuesday.
The government has announced anyone aged 18 years or younger in NSW will be able to create a bubble of three friends and visit each other's homes for play or study.
Mr Hazzard said the decision will have positive impact on the mental health of young people who have been in lockdown for months.
"Young people themselves, families generally, have been obviously finding it challenging that young people have not been able to have their friends over," Mr Hazzard told reporters.
Everyone in the bubble must live in the same local government area, and any adults in the household must be fully vaccinated.
The changes come just in time for the NSW school holidays but parents will not be able to interact with other adults in the household and can only drop the children off and pick them up.
The government says the new freedoms are a result of high vaccination rates.
Many parents in NSW have been juggling homeschooling, working from home and caring responsibilities at home while in lockdown.