A number of same-sex marriage surveys may include hidden rude and even offensive phrases after an oversight by the Australian Bureau of Statistics.

More than 16 million surveys were sent out by the ABS earlier this month to homes in all corners of the country, as people have their say on legalising same-sex marriage.

But with each survey including its own unique computer-generated barcode, among the millions sent out were a number featuring rude words - including one with 'bumsex'.

The Australian Bureau of Statistics has apologised over a same-sex marriage survey containing the phrase 'bumsex' (pictured) in its computer-generated barcode

The mistake forced the ABS' deputy statistician Jonathan Palmer to apologise for their oversight.

'The ABS acknowledges that in issuing 16 million barcodes it did not check and remove words and phrases that may be offensive,' he said in a statement.

'The codes were issued using an algorithm generating more than two quintillion combinations of letters and numbers in order to generate highly secure barcodes.'

Shared to social media, the photo caused an outpouring of comments from voters on both sides who found it humorous.

More than 16 million surveys were sent out by the ABS earlier this month to homes in all corners of the country, as people have their say on legalising same-sex marriage

The mistake forced ABS deputy statistician Jonathan Palmer to apologise for the oversight, while social media commenters seemingly found it hilarious (pictured)

'It would have been far more Australian had it been "BUMSEXM8",' one commenter said.

'Randomness is sometimes pretty awesome,' one wrote, while another said: 'Can't. Stop. Laughing.'

The closing date for the same-sex marriage postal vote survey is November 7.