An increasing number of public school teachers in NSW have quit their jobs in the past five years, with data showing those who gave up on the profession last year outpaced those who retired.
NSW Department of Education data detailing why teachers left the profession shows the number of permanent public school teachers who resigned has steadily increased each year since 2017.
During the same period, the number of teachers who retired fell from 2017 to 2020, before stabilising in 2021.
In 2021, the number of teachers who resigned exceeded those who retired, with 1159 quitting and 1142 retiring.
The data, seen by AAP, was provided to the NSW parliament during a recent inquiry into the state's teacher shortage.
Education and Early Learning Minister Sarah Mitchell accused the opposition of spreading mistruths about the education sector and misunderstanding the data.
"The basic fact is there are almost 10,000 more teachers in the system compared to 10 years ago," Ms Mitchell told AAP.
The workforce had grown by 15 per cent, compared with an enrolment increase of only 7.6 per cent, she said.
"Labor clearly believes increased funding and more teachers is a problem, so I look forward to their election commitment to slash teaching numbers and school funding," she said.
A spokesperson for the Department of Education said the numbers had been taken out of context and were therefore incorrect.
The size of the NSW teacher workforce - more than 92,000 - means a large number of teachers join and leave every year, the spokesperson said.
Some 5500 teachers were hired in 2021, a 45 per cent increase from the previous year.
Retention rates in 2021 could have been affected by COVID-19 restrictions and requirements.
NSW teachers have one of the best retention rates in the public service, second only to police.
However, President of the NSW Teachers Federation Angelo Gavrielatos told AAP resignations were being fuelled by burnout.
He said teachers were lumped with excessive amounts of administrative work, often logging 50 and 60-hour weeks.
"This is a crisis, and every projection indicates that it's going to get much, much worse," Mr Gavrielatos said.
"Teachers now have two jobs - one they signed up for, that's teaching, and the other one that's been imposed upon them, called administration."
Mr Gavrielatos said it was critical the government lifted wages and cut administrative work to retain teachers.
NSW teachers held a protest in Sydney on Wednesday, urging the government not to lock in a three-year award of 2.53 per cent a year.
With cost of living pressures and inflation about six per cent, the union has argued the award will cut teachers' pay.
Shadow Education Minister Prue Car said teachers were walking away at increasing rates because they were struggling with unmanageable workloads.
NSW Labor Leader Chris Minns says the data shows the government has failed to implement policies to incentivise teachers to stay in the classroom.
"This data puts in black and white the failure of the NSW Liberal government to effectively retain teachers," Mr Minns said on Friday.
"Teachers are leaving in droves due to this government's failure and it is our children's education which is suffering as a result."
Factbox:
Permanent public school teachers leaving the profession
Resignations vs retirements
2017
649 - 1836
2018
726 - 1565
2019
812 - 1320
2020
929 - 1088
2021
1159 - 1142