posteo.de is a free email provider
posteo.de is a consumer mailbox provider, so anyone can open an address there in a minute.
79 /100
Strong
Email authentication report card
What posteo.de publishes in DNS to stop other people sending mail in its name, read record by record.
Can mail be forged as this domain?
Yes, a forgery is delivered
DMARC is set to p=none, which only asks for reports, so a receiver that honours what this domain publishes is not told to reject a message with it in the From header, and delivers it.
- Weak
SPF ~all
The record ends in ~all. Mail from a host outside the list is only marked, not rejected, so it usually still arrives.
- Weak
DMARC p=none
A DMARC record is published, but p=none only asks for reports. Receivers are told to deliver failing mail anyway, so this stops no forgery.
A checker that reports "DMARC found" here is telling you nothing useful.
- Weak
MTA-STS testing
A policy is published in testing mode. Failures are reported but delivery still goes ahead over an unverified connection.
- Pass
DNSSEC Signed
The zone is signed, so the MX, SPF and DMARC answers above cannot be quietly rewritten in transit.
- Pass
TLS-RPT Published
Sending servers have an address to report failed TLS deliveries to.
Why it scores 79?
- Accepts mail through 4 MX hosts.
- A website answers on this domain.
- DNS answers for this domain are DNSSEC signed.
What to publish to close the gaps
The records posteo.de is missing, in the order they are worth doing. Owner names are written out in full, so they work whether your DNS panel wants a full name or a relative one.
Tighten SPF to -all
Nameposteo.deTypeTXTValuev=spf1 <your existing mechanisms> -allKeep the mechanisms you already have and change the final qualifier. Anything softer leaves the forgery path open.
Move DMARC off p=none
p=none blocks nothing. Once your reports show every legitimate sender passing, raise the policy to quarantine and then to reject.
Switch MTA-STS to enforce
Valuemode: enforceChange mode in https://mta-sts.posteo.de/.well-known/mta-sts.txt and bump the id in the TXT record. Testing mode reports failures but still delivers.
Questions about posteo.de
Every answer below is generated from the stored record for this domain.
Is posteo.de a disposable email domain?
Is posteo.de spoofable?
Does posteo.de publish SPF and DMARC?
Who handles email for posteo.de?
How old is the posteo.de domain?
How do I block posteo.de on my signup form?
Can I trust email from posteo.de?
Last verified . We recheck every domain on a schedule, and this report changes only when its records or its verdict do.