Source: Mandrill Zendesk

US – CAN-SPAM [ALWAYS ADD A PHYSICAL ADDRESS WITH THE UNSUBSCRIBE LINK]

Canada – C-28 

Australia – Spam Act 2003

EU Article 13 of DIRECTIVE 2002/58/EC OF THE EUROPEAN PARLIAMENT

The Directive is implemented by each member state independently so check particular country law for more details.

UK The Privacy and Electronic Communications (EC Directive) Regulations

Austria Telecommunications Act 2003

Belgium  Etat des lieux en juillet 2003, July 4, 2003

Cyprus Section 06 of the Regulation of Electronic Communications and Postal Services Law of 2004 (Law 12 (I) / 2004 deals with unsolicited communications (spam)

Czech Republic Act No. 480/2004 Coll., on Certain Information Society Services

Estonia Information Society Service Act

France Commission Nationale de l’Informatique et des Libertés ( CNIL Guidelines on email marketing

Germany

Art. 7 German Unfair Competition Law (Gesetz gegen Unlauteren Wettbewerb) (UWG)

Art. 202a, 263, 303a, 303b of the German Criminal Code Art. 6 of the German Law regarding Information Society Services Art. 28 Par. 4 of the German Data Protection Act

Italy Personal Data Protection Code (legislative decree no. 196/2003)

Netherlands Article 11.7 of the Dutch Telecommunications Act and Dutch Data Protection Act.

Sweden Swedish Marketing Act (Swedish Code of Statutes, SFS 1995:450).

Personal Data Act (Swedish Code of Statutes, SFS 1998:204), in so far as spam activities involve processing of personal data.

For more countries, check here.