Enumerators are beginning their final drive to ensure all residences in Ireland have census forms before this evening.
The first census since 2002 takes place tonight and all people in Ireland are required by law to fill out their forms.
Despite a large advertising campaign, the country's ethnic minority communities have said that many of them are unaware of the event.
Census forms are available in 11 languages, the largest number to date, however community representatives have claimed that ads could have been better directed towards immigrants.
Sing Wong, of the Irish-Chinese Cultural Society, said that despite the promotion that has been done many immigrants may not know about it.
"Many immigrants to Ireland do not watch TV and listen to the radio all the time, and then if it is in written form, like newspapers, it is not in their language."