Deliverability

Mail lands in spam after the move: SPF, DKIM and DMARC

12 Sept 2026·3 min read

A common complaint after a move: the archive is there, mail arrives, and your own messages turn up in the recipients spam folder. The migration has nothing to do with it — the sending server changed, and recipients do not know that yet.

Why it happens

Receiving servers decide the fate of a message from three questions: was this server allowed to send for your domain, was the message altered in transit, and what to do when the first two answers are no.

While the domain lived on the old host, the DNS records answered those questions about the old server. After the move the new server sends and the records still describe the old one — formally, an impostor is sending your mail.

The second factor is reputation. A new server has none yet, so a few days of extra suspicion are unavoidable even with perfect records.

The three records to set

All three live in the domain DNS and are configured once. The values come from the new mail provider — there is nothing to invent.

SPF — the list of servers allowed to send for your domain. There must be exactly one record: two SPF records break the check entirely.
DKIM — the signature the new server adds to outgoing mail, plus the public key in DNS that recipients verify it with.
DMARC — the policy for when SPF and DKIM do not line up: accept, quarantine or reject. Start permissive, with reports switched on.
PTR for your own server, if you send from your own rather than a provider: the reverse record must match the name used in the SMTP greeting.

The order of work

One sitting to fix, but it needs patience: DNS changes do not propagate instantly.

Get the SPF and DKIM values for your domain from the new provider.
Replace the old SPF record rather than adding a second one.
Publish the DKIM public key and enable signing on the provider side.
Set DMARC to a permissive policy with a reporting address, then tighten it after a couple of weeks.
Send test messages to mailboxes at a few large providers and read the check results in the headers.
If mail still lands in spam, check the domain against public blocklists: the old host may have left a legacy.

What will not help

Asking recipients to whitelist you treats the symptom for one person, not the problem.

A mass we-have-moved announcement from the new server on day one is a reliable way to damage a reputation that has not formed yet. Keep to normal volume for the first few days.

And separately: none of this has anything to do with the archive migration. Migrated messages already sit in their folders and are not going anywhere, even while outgoing mail is still being filtered.

FAQ

Common questions

Does the migration itself affect deliverability?

No. A migration copies the incoming archive; spam filtering applies to outgoing mail. Different things, configured separately.

Can I keep two SPF records?

No. Two SPF records count as an error and void the check. List every allowed server in one record.

How long after setting the records?

Usually hours to a day, the lifetime of DNS caches. Reputation for a new server takes weeks.

Is DMARC needed if SPF and DKIM are set?

Not technically required, but large receivers treat domains with DMARC noticeably better, and the reports show who else sends mail in your name.

Where to next

Move from hosting to Gmail Certificate verify failed explained All migration routes

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