A by-election was held for the New South Wales Legislative Assembly electorate of Smithfield on 23 June 1990 because of the resignation of Janice Crosio to successfully contest the 1990 federal election for Prospect.[1]
The Smithfield by-election was held the same day as the Heffron and Granville by-elections.
| Date | Event | |
|---|---|---|
| 17 February 1990 | Resignation of Janice Crosio. | |
| 24 March 1990 | 1990 federal election | |
| 25 May 1990 | Writ of election issued by the Speaker of the Legislative Assembly and close of electoral rolls.[2] | |
| 1 June 1990 | Nominations | |
| 23 June 1990 | Polling day | |
| 2 August 1990 | Return of writ |