The state government is sitting on more than $234 million from unclaimed refunds, overpayments, share dividends, bonds, uncashed cheques and unclaimed money from the sale of a property.
The average amount of money waiting to be returned is $391.
Those who are owed money must provide supporting documents to support their claim.
Revenue NSW will then send their funds within 28 days.
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Finance minister Courtney Houssos said the state had returned $21 million to households this financial year.
“With $230 million still available in unclaimed money for people in NSW, I encourage everyone to get online, search the register, and get the money that’s owing to you,” Houssos said.
State Revenue chief commissioner Scott Johnston encouraged residents to search through the register.
“We want to make sure everyone knows about the unclaimed money register, so they can jump online, find out if any money is owed to them and undertake the process to get it back,” Johnston said.
“That way we can ensure more money is being returned to those it belongs to, rather than sitting with us for extended periods of time after enterprises and organisations pass it on.”
The top areas in regional NSW with unclaimed money are Newcastle and Lake Macquarie with $7.4 million and the Illawarra with $5.8 million.