Those who use the archives can be divided into two broad groups. Private individuals approach the National Archives for a number of reasons. Frequently, they are looking for materials relating to them or their relatives: many need certificates or copies of records issued by institutions that have since made their records over to the archives. Most private users are interested in genealogy and many are looking for records of property rights. For the most part, their enquiries are dealt with in the Reading Room.

Many researchers, particularly historians, come to the archives in search of materials. The other main user group consists of staffs of public bodies and institutions that come for information in materials they have made over to the archives, or for advice on document management and deposition. Copies of records, or reading access to materials, are available subject to the provisions of law and other rules.

The National Archives of Iceland publishes catalogues and guides to their holdings for institutions and the general public. It also publishes academic works and maintains this website.