The general importance and impact of election polls, particularly in the preelectoral period, have led to their legal regulation. This process has generated a complex discussion about the appropriate regulation to give room to the different interests at stake. This paper critically analyzes the current regulations in comparative law that, on the one hand, set a period of blackout for the publication of polls and, on the other hand, set an obligation of disclosure to provide information for the understanding and evaluation of the polls' results. Comparative law is presented in a panoramic way and in deep cases are studied: United States, Canada, Spain, France, Colombia and Chile. It is observed that the obligations of disclosure are less problematic than the blackouts because they seem to minimize the restriction of free speech and freedom of information. However, by introducing some theoretical elements that serve to qualify and understand correctly the collective democratic interests at stake, a robust and satisfactory justification is identified not only for disclosures but also for blackouts.