NSW Treasurer Dominic Perrottet did not personally declare a donation from his former law firm, which has donated thousands of dollars to the NSW Liberals and receives significant government contracts.

Mr Perrottet did not declare a donation from his former employer Henry Davis York from March 2011. Henry Davis York has since merged with Norton Rose Fulbright.

NSW Treasurer Dominic Perrottet. Credit:Dominic Lorrimer

Henry Davis York has donated more than $17,000 to the NSW Liberal Party since 2010 and was also one of the highest billing firms on the government's payroll.

Mr Perrottet worked for Henry Davis York before entering parliament in the 2011 election.