How often should suppression audits occur?

Suppression audits should occur regularly to verify that suppression systems function correctly. Quarterly audits are common, with more frequent checks for high volume programs or after system changes.

Audits should verify that suppressed addresses are actually blocked from receiving mail. Test by attempting to send to known suppressed addresses and confirming delivery fails. Also verify new suppressions propagate correctly across systems.

Review suppression sources to ensure all channels feed into central suppression: bounces, complaints, unsubscribes, manual additions, and external feeds. Gaps in suppression sources create compliance and deliverability risks.