Survey forms asking Australians whether they support same-sex marriage will be posted from Tuesday.
The Australian Bureau of Statistics is aiming to get the forms out to 16 million voters by September 25.
The form asks a simple question, "Should the law be changed to allow same-sex couples to marry", followed by yes and no boxes to be marked.
The ABS will close receipt of forms at 6pm on November 7 and announce the result at 11.30am on November 15.
However the bureau is encouraging forms to be sent in by October 27.
Requests for replacement materials, if a problem occurs, will only be accepted between September 25 and 6pm October 20.
As proponents of the yes and no case ramp up their campaigns, Labor and the coalition are working on laws to ensure campaign materials do not include hate speech and all materials are properly authorised, as they are during elections.
It's expected the laws will pass parliament by the end of this week.