The 2016 Census includes registration by phone or Internet and must be completed in English by everyone in Australia on August 9.
There are already mounting concerns about the census, including over data privacy, and ability to access the Internet.
But now politicians and the group representing ethnic communities are warning some migrants and refugees have not received enough help to be able to complete the census.
Everyone in Australia on August 9 must complete the census, either online, on the phone or by post.
And the census can only be completed in English.
South Australian Labor MP Steve Georganas says the government hasn't done enough to inform people who aren't proficient in English about the census.
"We have the added issue of non-English-speaking background people who may miss out on the census and its very important that we get that information from different communities to ensure that resourcs are allocated in the future years for needs that may be required in different communities. I think the lead time has been botched up completely by the government, we just haven't seen much promotion of it and the biggest concern again is promotion in different languages for different communities who need to participate in the census so we get a true snapshot of the nation."
FECCA, the Federation of Ethnic Communities' Councils of Australia, says there would be a negative impact on migrants and refugees if they don't have the opportunity to complete the census.
FECCA says it has been reassured by the Bureau of Statistics, who runs the census, that measures have been taken to help and make sure everyone can complete the survey.
But FECCA's acting chair, Eugenia Grammatikakis, says despite that reassurance, members of ethnic communities, in particular the elderly, remain unsure.
"Whilst they have made a very significant effort to engage with ethnic communities there still appears to be quite a bit of a gap and certainly the feedback that we've been getting until today from telephone calls that we have been receiving and other contact that we have with our members, there is still a bit of concern out there and a bit of confusion."
Steve Georganas says if people don't fill in the Census, the allocation of resources to their communities could be affected.
"If they don't fill it in correctly, if the information isn't provided by different community groups, Indigenous groups etc, you'll never know what the issues are in particular groups to be able to support and provide services for a particular demographic in the future so its really important that we engage with every single citizen in the nation to be able to get a good broad picture of where we're heading, what the issues are, what our needs are and certainly the needs of smaller communities as well who perhaps English isn't their first language."
South Australian Senator Nick Xenophon is also hearing concerns from his constituents.
Mr Xenophon says if problems are not resolved Census data could be unreliable.
"It seems to me there's a lot of confusion and concern out in the community. The government hasn't dealt with it, if the census is meant to be a snapshot of Australia on August the 9th right now, it does look as though its going to be timelapse photography with a lot of blurred vision."
ABS Statistician David Kalisch says the Bureau has been inundated with calls, but he says Australians don't need to worry yet as the census cannot be filled in until August 9.
"Our hotline has been receiving more calls than we anticipated and we apologise to the Australian community for that but they don't need to respond and receive the information today or tomorrow, they have got plenty of time to respond and get back to our call lines to get the information they need."
Federal small business minister Michael McCormack has also tried to relieve people's concerns.
Mr McCormack says hundreds more staff have been brought on board to help with giving guidance on the Census.
He also made clear that only people who are unwilling to complete the census will be fined, and not people who had difficulty completing the census before the deadline.
"In the past few days the ABS has been responding to the efficiency of Australia Post, letters went out in some areas quicker than the ABS had anticipated and this created a backlog in the call centre. It has already taken well over 110,000 calls and I appreciate that some people have been trying to get on to the number and they've been put on hold. Hundreds of more staff have been brought on board and that followed discussions with the ABS and with government."
The last day the Census form can be completed is September 23.
