SMTP 554 5.7.1
transaction failed, message rejected as spam
SMTP 554 5.7.1 is a flat refusal: the receiving server has decided the message is spam, or that your sending IP or domain is not permitted to send to it. It is permanent, it is aimed at you rather than the address, and it usually means a blocklist or a reputation problem.
Should you remove the address?
Keep the address; fix the sending side
Keep it unless the text says the recipient does not exist. A policy block says nothing about the mailbox.
Block. Retrying changes nothing until the cause on your side is fixed.
How it appears
554 5.7.1 <[email protected]>: Relay access denied
554 5.7.1 Message rejected because it appears to be spam
554 5.7.1 Service unavailable; Client host [203.0.113.5] blocked
What causes it
- Your sending IP or domain is on a blocklist the recipient consults.
- Reputation is poor enough that the server refuses rather than filters.
- The message failed authentication and the recipient enforces it strictly.
- You are sending from an IP with no reverse DNS, or a mismatched HELO — a strong spam signal on its own.
How to fix it
In order — try the first one first.
- Check the major blocklists for your sending IP and domain immediately.
- Audit SPF, DKIM and DMARC on the sending domain and fix any alignment failure.
- Set reverse DNS on the sending IP so it matches the HELO name you announce.
- Then address the cause of the listing — a bounce or complaint spike. Requesting delisting without fixing the cause just produces a second listing.
Who sends it
Many self-hosted, corporate and filtering-gateway servers. Gmail, Microsoft and Yahoo don't list 554 5.7.1 in their published tables, so you will mostly see it from other systems.
Gmail, Microsoft and Yahoo don't publish wording for this code, so none is quoted here. The text in your own bounce is the best guide to the exact cause.
Common questions
- What does SMTP 554 5.7.1 mean?
- SMTP 554 5.7.1 is a flat refusal: the receiving server has decided the message is spam, or that your sending IP or domain is not permitted to send to it. It is permanent, it is aimed at you rather than the address, and it usually means a blocklist or a reputation problem.
- Should I retry a 554 5.7.1 error?
- No. 554 is a permanent failure, so the message will never be delivered no matter how many times you try. Remove the address — repeated sends to permanent failures are one of the main signals mailbox providers use to throttle a sender.
- How do I fix SMTP 554 5.7.1?
- Check the major blocklists for your sending IP and domain immediately.
- Is 554 5.7.1 a hard bounce or a soft bounce?
- 554 5.7.1 is a block rather than a classic hard or soft bounce. The rejection is about your sending (authentication, reputation, content or the recipient's policy), not about whether the address exists. Retrying changes nothing until the cause on your side is fixed.
- Should I remove the address after a 554 5.7.1 bounce?
- Keep it unless the text says the recipient does not exist. A policy block says nothing about the mailbox.
- Will verifying my list prevent 554 5.7.1?
- Not directly. This code is about your authentication, IP or domain reputation, so verification will not lift it. A clean list still matters, because mailbox providers weigh how often a sender hits addresses that don't exist.
Clean the list before the next send.
A bounce report only tells you about the addresses you already mailed. The rest of the list has the same kinds of dead mailboxes in it, and each one becomes a hard bounce recorded against your domain the moment you send.
- A real SMTP mailbox check on every row, before anything is sent
- Dead and mistyped addresses split out, so they never reach your sending tool
- Catch-all, disposable and role addresses flagged alongside
Plans from $9 a month, cancel anytime, no contract. Sign in with Google and your first 100 email checks are free, no card. The free tools stay free either way.
Other 554 replies
Sources
Provider wording is quoted only where the provider publishes it.
Last reviewed 2026-10-22