Article 23 Vienna Convention on Diplomatic Relations
1.The sending State and the head of the mission shall be exempt from all national, regional or municipal dues and taxes in respect of the premises of the mission, whether owned or leased, other than such as represent payment for specific services rendered.
2.The exemption from taxation referred to in this article shall not apply to such dues and taxes payable under the law of the receiving State by persons contracting with the sending State or the head of the mission.
See also: Article 22 Vienna Convention on Diplomatic Relations