The Australian Bureau of Statistics started sending out the material to the 16 million people eligible to vote in the survey on Tuesday.

The packs sent out across the nation will contain the survey form, a Reply Paid envelope and survey instructions. 

Bureau deputy Australian statistician and taskforce leader Jonathan Palmer said people should not delay returning their survey papers. 

“Look out for your survey form in the mail, complete and return it without delay to make sure your response counts,” he said.

Australia Post acting managing director Christine Corbett said the company would be doing all it could to deliver the survey material on time and for people to refrain from taking out their views on the person delivering the mail. 

“Our posties will continue to do the fantastic job that they do every day – delivering and collecting mail right across the country,” she said.

“We call on the community to respect the job they are doing during this process.”

The survey papers will be posted out over the next two weeks but if papers are lost or undelivered, replacements can be ordered between September 25 and October 20. 

All Australians are encouraged to return their forms by October 27 with the final deadline for forms to be received by the bureau on November 7.

Results of the Australian Marriage Law Postal Survey will be published on the Australian Bureau of Statistics website on November 15.