More by-elections for NSW as Piccoli quits

NSW is facing its fifth by-election this year following the early departure of former education minister Adrian Piccoli.

Premier Gladys Berejiklian confirmed on Sunday evening that Mr Piccoli would retire from state politics after 18 years in parliament.

Mr Piccoli is the second Nationals MP to quit this year, following member for Cootamundra Katrina Hodgkinson's early exit.

Mr Piccoli's retirement will trigger a by-election in the seat of Murray, on top of the upcoming polls in Cootamundra, as well as Blacktown following the retirement of former Labor leader John Robertson.

The Shooters, Fishers and Farmers Party is circling both regional seats, having wrestled the electorate of Orange from the Nationals in by-election last year.

Gosford and Manly were also re-contested in April with Labor and the Liberals each retaining their respective seats.

Nationals leader John Barilaro said the party would miss Mr Piccoli's experience, but claimed it provided an "opportunity for renewal".

"I thank Adrian for his extraordinary service and wish him all the best for his future endeavours," he said in a statement.