Open Settings > Organization. This area requires Full Access and Manage Settings.
Use the Case Numbering section to define identifiers for newly created cases.
Choose a preset or enter a format using the displayed Available Variables. Variables include two- or four-digit creation year, creation month, case type tag, series number, and case instance. Copy the exact token from the interface rather than typing an approximate name.
For example, {{Case.series_number}}-{{Case.series_instance}} combines the shared case series with its instance. The case type tag is configured under Case Types.
Format changes affect new cases only. Existing case numbers are not modified, and case numbers cannot be manually edited after creation. Public case requests have their own numbering settings.