The most common violations include setting cookies before obtaining user consent, using pre-ticked consent boxes, lacking a clear reject button on cookie banners, making it harder to refuse cookies than to accept them, and failing to provide adequate information about cookie purposes. The French CNIL and Italian Garante have been particularly active in enforcing these requirements.

France (CNIL), Italy (Garante), and Spain (AEPD) consistently lead in cookie consent enforcement. France has issued some of the largest fines, including multi-million euro penalties against major tech companies for cookie consent violations under both GDPR and the ePrivacy Directive.

Cookie consent fines vary enormously, from a few thousand euros for small businesses to hundreds of millions for large tech companies. The median fine for cookie-specific violations tends to be lower than general GDPR fines, but landmark cases like CNIL's fines against Google and Amazon have reached EUR 150 million and EUR 35 million respectively.

Cookie consent in Europe is governed primarily by the ePrivacy Directive (2002/58/EC, as amended by 2009/136/EC), often called the 'Cookie Directive', and the GDPR (Regulation 2016/679). Article 5(3) of the ePrivacy Directive requires prior consent for storing cookies, while GDPR Articles 6 and 7 define lawful consent requirements. National implementations vary by country.