Senate
The half-Senate election must then be held by mid-May 2022.
When can a ‘normal’ election be held? has a three-part answer:
- The first date for a normal house and half-Senate election is 7 August 2021, if announced this weekend and writs are issued by Monday 5 July.
- The last date for a normal house and half-Senate election is 21 May 2022. This date gives six weeks to complete the complex Senate count and allows Senators to be declared elected and start their terms on 1 July. A mid-May election would be announced in early April 2022.
- There is a highly improbable option for a half-Senate election by 21 May 2022 and a separate House election as late as 3 September 2022.
https://antonygreen.com.au/when-can-the-next-federal-election-be-held/