NSW public servants are reporting acts of serious wrongdoing at record levels, with a 30 per cent jump in disclosures made to authorities such as councils and government departments compared to the previous year.

Corruption was the major allegation levelled in 83 per cent of the 422 public interest disclosures made to government authorities in 2018-19, according to the NSW Ombudsman's annual report into the oversight of whistleblower legislation, tabled before state parliament on Thursday.

Most public interest disclosures to government authorities concern corruption. Credit:Michele Mossop

The report states there were more than 1500 public interest disclosures by both public officials and organisations in the past year, with just over 1000 of these made to the Independent Commission Against Corruption (ICAC).

Three-quarters of these were reports made by the head of a public sector organisation, who as of 2017-18 is required by law to notify the ICAC of any circumstance of suspected corrupt conduct.