The Egmont by-election of 1912 was a by-election held during the 18th New Zealand Parliament in the electorate of Egmont. The seat became vacant due to the resignation of Thomas Mackenzie after the fall of his government. The by-election was held on 17 September and was won by Charles Wilkinson.
The following table gives the election results:
|Liberal||David Lyon Abbott Astbury||2,139||43.9|
|Reform gain from Liberal||Swing|