substack.com email records

What substack.com publishes in public DNS for SPF, DKIM, DMARC, MX and BIMI, resolved on 2026-08-04.

SPF

v=spf1 include:_spf.google.com include:mailgun.org include:mail.zendesk.com ~all

The record authorises these sending platforms: Google Workspace, Mailgun, Zendesk.

DMARC

v=DMARC1; p=reject; pct=100; rua=mailto:re+kvnosxqvppz@dmarc.postmarkapp.com; sp=reject; aspf=r;

policy

p=reject

subdomains

sp=reject

applies to

100% of mail

reports

mailto:re+kvnosxqvppz@dmarc.postmarkapp.com

alignment

adkim=r, aspf=r

DKIM

Keys found on 1 of 10 probed selectors:

MX

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The above is a snapshot from 2026-08-04. Re-resolve it now:

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