550-5.1.1
550 5.1.1 Recipient Address Does Not Exist
Gmail could not deliver the message because the destination mailbox does not exist.
Typos, stale data, or deactivated Google Workspace accounts cause 5.1.1 failures. Treat them as hard bounces and stop retrying immediately.
Severity
ERROR
Provider
Gmail
Reference
Mitigation Portal
Last Reviewed
2025-06-01
How to Fix 550-5.1.1
Follow these steps to resolve this Gmail SMTP error and restore normal delivery.
- ✓Remove the address from your mailing list after the first bounce.
- ✓Validate addresses at form submission and during imports.
- ✓Offer subscribers a self-service profile center to keep data current.
- ✓Alert customer success teams when key accounts bounce so they can confirm addresses.
Helpful Resources
More Gmail SMTP Codes
Keep these related troubleshooting guides handy while addressing 550-5.1.1.
Still experiencing Gmail delivery issues?
Run your domain through our free deliverability tools or book a session with Bento's deliverability specialists.