Duplicates inflate costs, distort reporting, and risk double-sending if your platform does not deduplicate at send time . Deduplicate before import using email address as the primary key, supplemented by fuzzy matching on name and postcode to catch household duplicates. Most email platforms offer deduplication on upload—Mailmodo and SendFox, for example, automatically skip duplicate e... https://www.b2cemaillist.com/australia-b2c-email-list/