What are the steps to write an email retention schedule that maps mailboxes to records series?

An email retention schedule treats email as the records it actually contains, not as a single undifferentiated pile. The goal is to connect each mailbox (or group of mailboxes) to one or more records series, each with a defined retention period and disposition. The work is part records analysis, part stakeholder coordination.

Inventory mailboxes and their functions

Start by listing the mailboxes in scope: individual user accounts, shared/role-based boxes, distribution lists, and journaling or archive stores. For each, capture the business function it serves and the kinds of records it produces. A leadership mailbox, a help-desk queue, and a contracts inbox will map very differently.

Identify the records series email touches

Map the content to your existing records series rather than inventing email-specific categories. Most email falls into a handful of buckets: transitory or non-record messages, routine administrative correspondence, and substantive program or policy records. Where authoritative schedules already exist, align to them so retention is consistent across formats. See the email and messaging topic hub for related guidance.

Assign retention and disposition

For each mailbox-to-series mapping, document:

• Trigger — when the retention clock starts (date sent/received, case closure, end of fiscal year).
• Retention period — how long the series must be kept under your governing rules.
• Disposition — destruction or permanent transfer, and the method.

Where multiple series share a mailbox, set rules at the message or folder level, or capture records into a managed repository so they leave the mailbox under their own series.

Validate, approve, and operationalize

Review the draft with records, legal, privacy, IT, and the business owners. Confirm that any active legal holds suspend disposition. Once approved, translate the schedule into enforceable settings in your email platform and document the mapping so it can be audited and updated.

Maintain it

Re-examine the schedule when roles, systems, or legal obligations change. A schedule that is never revisited drifts out of alignment with how people actually use email.

ISO 15489 frames this as systematically appraising records and assigning authorized retention; NARA’s policy guidance reinforces that disposition must rest on an approved schedule, not ad hoc deletion.