The NSW Anti-Corruption Commission is receiving 50 to 70 referrals every week and the watchdog's chief warns it is unable to take on further investigations.
Despite an 11 per cent funding boost for the commission in the June budget, the agency says it has reached a full workload after years of prior cuts.
"At the moment, and I've made this point to the premier as well, the commission does not have spare capacity," ICAC Chief Commissioner John Hatzistergos told a budget estimates hearing on Wednesday.
"If the parliament was to pass a resolution asking the ICAC to take on an investigation, the only way we could do that is by taking people away from current projects."
The former District Court judge and attorney-general said his commission has seven preliminary investigations and four full investigations afoot.
Those include the inquiry that led Gladys Berejiklian to resign as premier in 2020 when she was compelled to admit she'd been in a relationship with her parliamentary secretary, Wagga Wagga MP Daryl Maguire.
ICAC is also investigating alleged corruption at two Sydney councils and the roads authority.
The commission fielded a record 3570 referrals in the year to June, an average of 9.8 a day.
This financial year is similarly high, sitting at 557 two months in.
Mr Hatzistergos said the $3.5 million funding boost in the June state budget would allow for 17 new full-time equivalent positions.
But the recruitment and vetting required for people working for ICAC meant it was still suffering from cuts in 2016.
"Letting people go is relatively easy. Putting people on takes time," Mr Hatzistergos said.
His predecessor had called for ICAC to be funded by the parliament, not the executive government.
The government instead agreed to separate funding for commissions such as ICAC and the Auditor-General through a separate unit of Treasury, which will develop a charter of independence.
Efficiency dividends - forcing agencies to find savings each year - will no longer apply.
Labor says it will legislate to guarantee independent funding for ICAC, if elected in March.
"A strong and independently funded ICAC is critical to restoring public faith and confidence in government," opposition special minister of state spokesman John Graham said on Thursday.