Australians in remote locations or travelling overseas will be offered a "paperless vote" on same-sex marriage rather than a postal vote.

Key points: Paperless option could include online form or text message

Paperless option could include online form or text message ABS will clarify what form a paperless vote will take early next week

ABS will clarify what form a paperless vote will take early next week Bureau says it has learnt from its failings during the census website outages

The Australian Bureau of Statistics (ABS) has responded to concerns many Australians may not receive a ballot in the mail before votes are due back on November 7.

Deputy statistician Jonathan Palmer said there were a number of options under consideration to ensure everyone who wanted to vote, could do so.

"It could be an online form, it could be a touch-tone telephone solution, it could be an SMS text message but we are still working out what could be the best option for a paperless return," Mr Palmer said.

The ABS will clarify what form a paperless vote will take early next week.

The delay may be due to the fact the bureau was not told it would be leading a national postal vote on same-sex marriage until the day before it was announced by the Prime Minister.

Chief statistician David Kalisch was first told about the ABS involvement on August 7, the same day the Liberal Party rejected a push for a free vote in Parliament.

ABS defends reputation after census bungles

The ABS was heavily criticised for website outages during the 2016 census, but Mr Palmer rejected claims it was not qualified or able to manage the process.

He said the ABS had learned from its failings during the census and was confident the ballot would not face similar problems.

"The 2016 online form outage did hurt the reputation of the ABS, we acknowledge that," Mr Palmer said.

"I can assure you that we have reflected and learned from the lessons of the 2016 census."

ABS officials said a paper ballot was not ideal and there was no way to stop people stealing letters in the mail or tampering with the votes.

"Our fraud plan will outline a range of mechanisms to ensure that we only process one return for every eligible Australian," Mr Palmer said.

Mr Palmer said he understood the public was, "very sensitive to concerns about privacy and confidentiality".

"I would like to stress this is a voluntary survey, only those who wish to provide their views need respond," he said.

"Those who wish to keep their views private can do so, but those who do share their view with us can be confident it will be kept secret".