Email DNS Check

Mailchimp SPF Not Working – Fix include:servers.mcsv.net (2026)

Mailchimp SPF fails when include:servers.mcsv.net is missing, published on the wrong domain, or blocked by duplicate SPF records. This often happens when marketing DNS changes are made separately from transactional sender policies. Mailchimp then sends, but SPF does not authorize the actual path cleanly. Start with your SPF record status and then check for multiple SPF records if things still look off.

Last updated: 3/27/2026

If your SPF setup is complex, review the SPF lookup limit guide.

Learn the bigger picture in our Email Authentication Explained guide and compare SPF vs DKIM vs DMARC to understand how these protocols work together.

One-Minute Fix

Add include:servers.mcsv.net to the existing SPF record on the real sending domain and keep only one SPF TXT record. Merge Mailchimp with other active providers in a single v=spf1 policy.

Correct Mailchimp SPF record
DNS TXT
example.com TXT "v=spf1 include:servers.mcsv.net -all"

This authorizes Mailchimp for the domain. If multiple services send mail, combine their includes in the same SPF record rather than publishing multiple SPF entries.

Run free check

Free live DNS check. No signup required.

Wrong vs correct setup

Wrong setup

Wrong setup
DNS TXT
example.com TXT "v=spf1 include:_spf.google.com -all"
example.com TXT "v=spf1 include:servers.mcsv.net -all"

Two SPF records cause policy conflict and can produce SPF permerror. Even with Mailchimp included, receivers may not evaluate SPF reliably.

Correct setup

Correct setup
DNS TXT
example.com TXT "v=spf1 include:_spf.google.com include:servers.mcsv.net -all"

This single merged SPF record authorizes both Google Workspace and Mailchimp. Receivers can evaluate one clear policy and Mailchimp traffic can pass SPF.

Why this happens

Mailchimp SPF setup is straightforward, but failures happen when teams add a second SPF record instead of merging mechanisms. Problems also appear when updates are applied to the wrong sending domain or when syntax issues break the final record. SPF supports one policy per domain, so structure matters as much as the include value. This is especially common when multiple SPF records are published or when DNS lookup limits are exceeded.

Why this is a problem

If Mailchimp mail fails SPF, campaign traffic can look less trustworthy to receivers and engagement messages can be filtered more aggressively. DMARC alignment can also fail when SPF was expected to provide the aligned path for marketing sends. For many senders the concrete symptom is a syntax error or a record that is too long for DNS to handle cleanly.

How this affects deliverability

Marketing mail depends heavily on consistent authentication at scale. Missing or broken Mailchimp SPF authorization can increase spam-folder placement, reduce sender trust, and create DMARC alignment issues across campaign traffic. You can see this clearly in neutral SPF results or when softfail vs fail decisions tip borderline mail into spam.

Common causes

  • include:servers.mcsv.net was missing from the active SPF policy.
  • A duplicate SPF record was added for Mailchimp instead of merging.
  • SPF changes were applied to the wrong domain or hostname.
  • Syntax errors in the SPF record caused invalid evaluation.
  • DNS propagation delays left providers seeing outdated SPF values.

What we checked

We checked for one valid v=spf1 record on the sending domain and verified whether include:servers.mcsv.net exists in that active policy. Missing include or duplicate SPF records commonly explain Mailchimp SPF failures.

Live DNS lookup. No login. No saved domains. No tracking.

FAQ

Do I need a separate SPF record just for Mailchimp?

No. SPF allows one v=spf1 record. Add Mailchimp include to the existing SPF policy and merge other senders there.

What does include:servers.mcsv.net do?

It authorizes Mailchimp’s sending infrastructure defined in its SPF policy to send mail for your domain.

Why is Mailchimp SPF still failing after updates?

The usual causes are duplicate SPF records, wrong domain targeting, syntax issues, or propagation delay on DNS changes.

Next steps

  • Send a real Mailchimp campaign/test and confirm the evaluated sending domain.
  • Add include:servers.mcsv.net to that domain’s existing SPF record.
  • Merge all providers into one SPF policy and remove duplicates.
  • Validate SPF syntax and wait for full propagation.
  • Re-test SPF and DMARC alignment using fresh Mailchimp traffic.
  • Review the full troubleshooting guidance in the SPF Hub.
  • Check signing and selector issues in the DKIM Hub.
  • Review alignment and policy issues in the DMARC Hub.

Related fixes

Explore more issues