The Associate Institute status is intended for universities or research labs that are on the path to joining ATLAS as a full institutional member.

The Associate Institute is hosted by a current ATLAS full-member Institution, which takes some responsibility for the associated group. Members of the Associate Institute will collaborate with the host Institution. There should be clear benefit shown to the Institution being joined, as well as to ATLAS, from the application.

Associate Institutes do not appear on the list of Institutions in the ATLAS author list. Scientific authors from Associate Institutes instead appear as authors of the host Institution, with an “Also at [Associate Institute]” footnote upon request. Associate Institutes are generally not a visible part of the ATLAS Collaboration. They do not appear in the CERN "Grey Book", nor do they have the right to open a Team Account at CERN based on their ATLAS Associate Institute status.​

• Initial contact should be made with the team leader of the Institution proposed, or directly with the ATLAS Spokesperson, who will put the group in touch with nearby member Institutions, if appropriate. In any case, informal contact should be made at an early stage with the Spokesperson and with the NCP of the nation concerned.
• The applicant group should prepare a short statement of interest, including a description of the general structure (staff, students, engineers) and background of the group, expectations for its evolution, specific interests (projects, activity areas in ATLAS) and work programme. It is expected that members of the applicant institute will begin qualification to become ATLAS authors.
• Statements of support will be required from the team leader of the Institution being joined and the NCP, who should also ensure that the funding agency concerned is in agreement.
• With an Associate Institute joining, the institutional responsibilities (M&O and OT shares) are increased. These are assigned to the host Institution, which should agree with the Associate Institute how they will be met. Payment of the additional M&O contributions will start for the calendar year after admission.
• The acceptance of an Associate Institute is at the discretion of the Spokesperson and Collaboration Board chair. The Collaboration Board shall be informed and comments solicited, before acceptance is implemented. The admission of a new Associate Institute does not require a CB vote or endorsement by the RRB, as the CB composition is unchanged.