Local Government minister Shelley Hancock said eligibility criteria for pre-poll voting is more relaxed this year to ease election day crowds on December 4.

"One of the measures taken to ensure COVID-safe elections this year is the relaxing of eligibility criteria to vote during the pre-poll voting period," Ms Hancock said.

"This will mean voting will not occur on a single day but over an election period of 12 days, including election day, to help with social distancing at polling places."

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Early voting opened at Cessnock and Kurri Kurri on Monday, with the Branxton pre-poll to follow next week.

Returning officer Colleen Williams said people turned out in "unprecedented" numbers on Monday, with about 500 votes cast across the Cessnock and Kurri sites - approximately double the amount usually seen in a day.

Ms Williams said about 30 people have been employed across the three pre-poll sites, including extra people to help with cleaning.

Voters are also encouraged to bring their own pen.

The Cessnock pre-poll is located Shop 7, 195-205 Wollombi Road (the former Anytime Fitness premises) and the Kurri Kurri pre-poll is at the community centre (251 Lang Street).

Both sites are open from 9am to 5pm Monday to Saturday this week, and Monday to Friday next week.

The Branxton pre-poll will open at the community hall (35 Bowen Street) on Monday, November 29 and will run from 9am to 5pm until Friday, December 3.

Eligible residents can also register to vote online, or by post if they cannot make it to a polling booth on election day.

People can also vote by post if they are self-isolating because of COVID-19, are living in a retirement village or nursing home, are in hospital, or reasonably believe attending a polling place on election day will pose a risk to their health or safety, or the health or safety of others.