NSW Health confirmed the case, a man in his 50s, this morning after unconfirmed reports an infected person from Queensland travelled to the popular beach town.
Contact tracing is now underway.
"As a precaution everybody who is in the following local government areas should immediately isolate and have a COVID-19 test if they have even the mildest of symptoms: Byron Shire, Richmond Valley, Tweed, Lismore, Kyogle and Ballina," NSW Health said.
Earlier today, when asked about the potential development, Queensland Premier Annastacia Palaszczuk said: "We're starting to hear some issues around that."
She said her team was waiting to "get more information" from their NSW counterparts.
The traveller may have also spent time in Lismore, a NSW town 45 kilometres west of Byron, while they were infectious.
More to come