ACT can carry out snail mail interviews, canvassing respondents with enveloped questionnaires to be returned via delivery person or mail service. In this case respondents are provided with self-administered questionnaires, which they fill in alone (without the need for an interviewer) and then mail or send back to the research center.

Mail surveys are usually applied in panel or inter-organizational studies. The collection of data by this method is relatively more time consuming, however it is sometimes the best way to carry out certain types of studies, particularly when multiple issues are being researched simultaneously, or when the respondents’ confidentiality is paramount.