What are best practices for cross-system suppression sync?

Cross system suppression sync best practices include defining a master source of truth that all systems reference. This might be a central database or designated primary system from which others pull updates.

Synchronization should be near real time or at minimum before each send. A suppressed address must be blocked everywhere before another message goes out. Batch sync overnight is inadequate for daily senders.

Audit trails should track sync operations. Log when suppressions propagate to each system. This enables troubleshooting when suppressions fail to apply and demonstrates compliance with opt out honoring.