What Data Retention Policy settings are available in Marketing Cloud, and how do they affect data extensions?

Data Retention Policies can be configured on individual Data Extensions to automate data lifecycle management:
Retention options for individual records:
— Keep all records and data extension: No automatic deletion — default.
— Delete individual records: Delete records older than N days, or delete records before a specific date.
— Delete all records and data extension: Deletes the entire DE (records and schema) after a specified period.
Timing: Retention jobs run daily at a system-scheduled time, not at a precise user-defined time.
Best practice: Set retention policies on high-volume send logs, tracking DEs, and temporary import DEs to prevent unbounded growth. Always retain records long enough for suppression, compliance, and analytics needs — typically at least 6 months for send tracking DEs.
Contact Builder consideration: Data retention on a DE does not automatically delete contact records from Contact Builder; use the Contact Delete API for GDPR-compliant erasure.