Moving sending domains without losing placement

Mailbox providers judge a new sending domain from scratch. Sending the full list at the old volume on day one is the most common way to lose placement after a move.

Work in this order. (1) Confirm SPF, DKIM and DMARC are correct and aligned on the new domain, and that the records actually resolve; automatic setup in an ESP does not guarantee correct DNS. (2) Warm gradually, starting with your most engaged contacts and widening as complaint and bounce rates stay low. (3) Suppress contacts with no recent engagement so early sends carry strong engagement signals.

If possible, run the old and new domains in parallel during the transition. Follow Google's sender guidelines and Yahoo's sender requirements for bulk senders.