Definition
Sender reputation: The trust mailbox providers place in a sending domain and IP address, built from bounces, spam complaints, trap hits, engagement and authentication over time. It decides whether new mail is delivered to the inbox, filtered to spam or rejected.
What affects sender reputation
Complaints weigh the most, because they are a direct statement from the recipient. Bounces come next: many unknown-user rejections signal an old or bought list. Spam trap hits and blocklist listings sit in the same category.
Authentication sets the baseline, since providers need SPF, DKIM and DMARC to know whose reputation a message belongs to. Engagement, such as opens, replies and moving mail out of spam, and steady volume do the rest.
Domain reputation vs IP reputation
IP reputation belongs to the server that sends. On a shared IP at an email platform, you share it with other customers.
Domain reputation follows the domain in your From address and DKIM signature, wherever you send from. Large providers now lean on domain reputation, so switching platforms does not reset it.
How to repair a damaged sender reputation
Stop mailing the segments that caused the damage, usually old or unverified ones. Verify what remains and suppress everything undeliverable.
Then send only to your most engaged recipients for a few weeks and raise volume gradually as placement recovers. Fix any authentication gaps while you do.
How RocketVerifier handles it
Verification protects the inputs reputation is built from: bounces, trap patterns and complaints from addresses that never wanted your mail. Our probes come from dedicated verification IPs and a dedicated verification domain, never yours, and no email is sent, so checking a list leaves your own reputation untouched. Monitors recheck SPF, DKIM, DMARC and blocklist status on a schedule and alert you when something changes.