The polls have now closed in Kiama after thousands of residents voted on their new representative to replace former MP Gareth Ward.
The disgraced state parliamentarian was forced to resign after being convicted of sex offences and then losing a fight to prevent his expulsion from parliament.
Officials have begun counting as of 6pm today, with results expected later tonight.
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According to the NSW Electoral Commission, more than 21,000 residents voted early at pre-polling booths and through postal voting.
The race is looking to be largely between Labor candidate Katelin McInerney and Liberal candidate Serena Copley, who had their last-minute pitches to voters.
"This is about representing the community with a strong local voice who understands their needs," Copley said.
While McInerney said her focus was on education and infrastructure.
"I can tell you what the top line for people are. It's getting Tripoli Way built, it's getting a public school happening in Coldwood," she said.
"It's making sure that we are not letting our schools get back to the state of disrepair."
Thirteen candidates are on the ballot, including Greens candidate Tonia Gray.
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Major parties and independent candidates were out on the campaign trail yesterday in a bid to secure votes.
Premier Chris Minns and Opposition Leader Mark Speakman both toured the South Coast alongside their party's candidates in a show of support.
Minns admitted he was "nervous" about the race.
Whoever wins will have less than 18 months to win the trust of voters until the next state election.
But early predictions say Labor, which held the seat since its creation in 1981 until losing it to Ward in 2011, is looking at a landslide win.
Today's by-election was triggered by Ward's abrupt resignation as Kiama MP on August 8, moments before his colleagues were set to vote on the first motion of expulsion in parliament in 107 years.
He had lost his legal bid to delay the state's parliamentarians from tabling the motion.
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The 44-year-old was convicted in July of four sex offences against two young men in 2013 and 2015.
Ward has held the Kiama since 2011, winning three elections under the Liberal banner before securing the 2023 poll as an independent.
He won the last election despite being charged with sex offences.
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