Those who fail to do so will face fines.
The census, the first since 2011, was launched at the beginning of April to collect key statistical data about the country.
The census form can be completed online or with the help of an official during a telephone call or home visit.
The survey is expected to provide the government with information about the number of people living in the country, their occupation, living standards, ethnicity, education and religious identity.
Agnieszka Bielawska has this report.
Click on the audio player above to listen.