The PES is a household survey conducted by specially trained interviewers starting about three weeks after Census night. This is a different collection methodology to the Census, where most forms are self-completed. A major advantage of interviewer-administered questionnaires is that people can be provided with assistance if they are uncertain about the meaning of any questions.

For each dwelling selected in the PES, the any responsible adult (ARA) methodology is used. This generally involves a single person in the dwelling responding on behalf of all persons present or usually resident. In addition to obtaining basic demographic information, questions are asked about each person's usual residence, location on Census night, and any other addresses where they might have been counted in the Census.

Using this address information, the corresponding Census forms are examined at the Census data processing centre to confirm how many times each respondent in the PES was counted in the Census. The results of this process are then combined and weighted to produce an estimate of net undercount in the Census.

In the 2006 PES, a sample of about 39,000 private dwellings (PDs) was selected (about half of 1% of all dwellings in Australia). The total number of people included in the PES was about 86,000. The sampling fraction varied between states and territories, with the smaller states and territories having higher sampling fractions to ensure adequate reliability of estimates.

The 2011 PES sample size is slightly larger than that for 2006, with around 41,000 dwellings selected. Additional information on the 2011 sample is provided in the Sample Design section of this paper.