The bill was put to a vote on Thursday evening, winning by 53 votes to 36.

"NSW is the only state to have no legislated this compassionate reform and it is time we ... moved forward with this safe, compassionate end of life option," the Sydney MP who spearheaded the bill, Alex Greenwich, said before the vote.

The Legislative Assembly now faces a potentially lengthy debate on more than 160 amendments to the bill that have been lodged by supporters and opponents.

That debate will continue into Thursday evening and into Friday, the last sitting day of the year.

Some of the amendments are from supporters who wish to address concerns raised in the debate.

Mr Greenwich said he was working collaboratively with many MPs who've put forward amendments.

But, he said, "there are some amendments that were literally lodged at midnight and others that are coming thick and fast".

"I don't believe that last-minute amendments on complex matters if is how we make good laws," he told parliament.

The 167 proposals include labelling VAD medication "poison" and changing the name of the bill to something more inflammatory.

Nevertheless, Mr Greenwich is optimistic the lower house debate can be finalised before parliament retires for the year on Friday.

"There is sufficient time to be able to resolve it and I think it's in the parliament's best interest to see if we can resolve it this year."

Mr Greenwich earlier thanked other MPs for three days of "very respectful, open and indeed emotional" debate.

Both Premier Dominic Perrottet and Opposition Leader Chris Minns opposed the bill, but allowed their MPs a conscience vote.

Health Minister Brad Hazzard was among the MPs to speak in favour of the bill on Friday.

He hadn't supported euthanasia for the first 29 years of his three-decade career in parliament, he said, but this bill was different.

Mr Hazzard became emotional as he recalled holding his mother's hand and asking her to squeeze it if she wanted palliative care, knowing that death might come more quickly if she did.

His mother squeezed his hand. She died the next day.

Mr Hazzard said that voluntary assisted dying did not "remove the importance of the value of palliative care."

"What it does do is give choice to those who are approaching the end of their life, to those who might suffer (what) none of us would want family members or friends or anyone to suffer, to enable that person to control their own passing."

He also said he couldn't withhold a right from NSW residents that Australians in all other states had.

Attorney-General Mark Speakman and Police Minister David Elliott spoke in opposition to the bill when debate resumed on Thursday.

If it passes the upper house, the bill will make NSW the last state in Australia to permit voluntary assisted dying.

The proposed legislation restricts euthanasia to terminally ill people who would die in no more than 12 months.

Two doctors will have to assess applicants, and the bill makes a criminal offence of attempting to induce a person to apply for voluntary assisted dying.

Australian Associated Press