Comments

The first national electoral Act was enacted not until 1902. Whilst it made provision for postal voting it required the ballot to be completed before certain public officials available in Australian towns (e.g. a school teacher). The AEC records that true postal voting was not available to anyone until 1906: see AEC Electoral Pocketbook (AEC, Revised Ed 2009) section 3.1 ‘Events in Australian Electoral History’ at p. 26. 

But a continuing need for an authorized witness to the postal vote application meant postal voting was impractical for Australians abroad until 1949: there was also the simple fact that airmail did not exist even between UK and Australia until 1931: Australian elections were not on fixed dates and law limited campaigns to 6 (typically 4 or 5 weeks) in which time the postal ballot had to be applied for, dispatched, and returned, all with the‘authorized witness’ problems.

Overseas military voting was however facilitated by law during WWI and WWII.