A by-election for the seat of Uralla-Walcha in the New South Wales Legislative Assembly was held on 9 June 1900 because of the resignation of William Piddington (), ostensibly for private reasons and was a candidate for re-election. It would appear that Piddington resigned due to insolvency as he was made bankrupt on his own petition on 25 May 1900.
The by-election for Canterbury was held on the same day.
<includeonly> William Piddington resigned.</includeonly>
While William Piddington was re-elected, he died on 27 September 1900, resulting in a further by-election, where the seat was retained by the Protectionist party.