What does a sudden drop in SPF records in Gmail Postmaster Tools mean?

Summary

A sudden drop in SPF records reported in Gmail Postmaster Tools can be attributed to various factors. Some reports indicate it might be a temporary issue with Google Postmaster Tools (GPT) due to data lag or false positives. However, most sources emphasize the importance of investigating potential underlying problems. These include SPF record misconfigurations, new or failing authentication sources, exceeding DNS lookup limits, and changes made by third-party vendors or ESPs. More serious issues could involve phishing attacks, domain spoofing, or problems with email forwarding. Ensuring proper DMARC alignment and regularly monitoring and updating SPF records are essential for maintaining email deliverability. Aggressive filtering practices by Gmail and unauthorized use of your domain could also contribute to the drop.

Key findings

  • GPT Issue: Potential temporary issue with Gmail Postmaster Tools (data lag, false positives).
  • SPF Misconfiguration: Incorrect or missing sending sources in SPF records.
  • Authentication Problems: New sources not authenticated or existing sources failing authentication.
  • DNS Limit Exceeded: SPF records exceeding DNS lookup limits.
  • Phishing/Spoofing: Domain targeted by phishing or spoofing attacks.
  • Email Forwarding: SPF alignment issues caused by email forwarding.
  • Third-Party Changes: Changes by ESPs or third-party vendors affecting SPF.
  • Unauthorized Use: Potential unauthorized use of domain for spam sending.
  • Gmail Filtering: Aggressive filtering practices by Gmail affecting SPF results.
  • DMARC Alignment: Issues with DMARC alignment, impacting deliverability.

Key considerations

  • Investigate Records: Thoroughly investigate SPF records for misconfigurations.
  • Verify Sending Sources: Verify all legitimate sending sources are included in SPF records.
  • Monitor SPF: Regularly monitor SPF records using available tools.
  • Update Records: Keep SPF records updated with valid senders.
  • Strengthen DMARC: Implement/strengthen DMARC policies to combat phishing/spoofing.
  • Consider SRS: Consider SRS (Sender Rewriting Scheme) for forwarding issues.
  • Align Strategy: Align email authentication strategy with vendors/ESPs.
  • Check Infrastructure: Examine sending infrastructure for potential problems.
  • Monitor Traffic: Monitor email traffic patterns for anomalies.
  • Authentication Audit: Conduct a complete email authentication audit.

What email marketers say
14Marketer opinions

A sudden drop in SPF records in Gmail Postmaster Tools can be attributed to various factors. Some sources indicate it might be a temporary Google Postmaster Tools (GPT) issue due to data lag or false positives. However, it is crucial to investigate potential issues such as SPF record misconfigurations, new or failing authentication sources, exceeding DNS lookup limits, or changes made by third-party vendors. It could also indicate more serious issues like phishing attacks, domain spoofing, or problems with email forwarding, necessitating the implementation of DMARC policies or SRS. Regular monitoring and updating of SPF records, as well as ensuring DMARC alignment, are essential for maintaining email deliverability.

Key opinions

  • GPT Issue: Gmail Postmaster Tools might report false positives or data lag.
  • Misconfiguration: SPF record may be misconfigured, with missing or incorrect sending sources.
  • Authentication Failure: New sending sources might not be authenticated, or existing sources may be failing.
  • DNS Lookup Limit: SPF records might be exceeding the DNS lookup limit, requiring flattening.
  • Phishing/Spoofing: Domain might be targeted by phishing or spoofing attacks.
  • Email Forwarding: Email forwarding can cause SPF alignment issues, requiring SRS.
  • Third-Party Changes: Changes made by third-party vendors or ESPs may affect SPF pass rates.

Key considerations

  • Investigate: Thoroughly investigate potential misconfigurations or changes in SPF records.
  • Verify: Verify SPF records to ensure all legitimate sending sources are included.
  • Monitor: Regularly monitor SPF records using available tools.
  • Update: Regularly update SPF records with all valid senders.
  • Implement DMARC: Implement or strengthen DMARC policies to protect against phishing and spoofing.
  • Consider SRS: Consider Sender Rewriting Scheme (SRS) for email forwarding issues.
  • Align: Confirm and align email authentication strategy with third-party vendors or ESPs.
Marketer view

Marketer from Email Geeks answers explaining that data lag seems to be the explanation.

June 2021 - Email Geeks
Marketer view

Marketer from Email Geeks explains that the issue is that GPT starts displaying yesterday's date, without having the data yet, and this is seen in several accounts, different ESPs as just noise again.

June 2024 - Email Geeks
Marketer view

Marketer from Email Geeks responds stating that this is a GPT issue, and that lots of folks are reporting it.

March 2022 - Email Geeks
Marketer view

Email marketer from SendGrid Blog explains that the decrease in SPF alignment can be caused by email forwarding, where the original SPF record doesn't match the forwarder's domain. He suggests considering SRS (Sender Rewriting Scheme) to fix this.

March 2022 - SendGrid Blog
Marketer view

Email marketer from Email on Acid Blog (now Litmus) responds that a reduction in SPF pass rates might stem from changes made by third-party vendors or ESPs; confirming and aligning your email authentication strategy with those changes is critical to maintain optimal deliverability.

February 2024 - Email on Acid Blog (now Litmus)
Marketer view

Email marketer from Reddit shares that a sudden drop in SPF records reported by Gmail Postmaster Tools can often indicate a misconfiguration or change in your SPF record. It's crucial to verify your SPF record to ensure all legitimate sending sources are included.

August 2024 - Reddit
Marketer view

Email marketer from MXToolbox Blog mentions that monitoring your SPF records regularly using tools available on MXToolbox can help you detect issues early and prevent significant drops in your email deliverability due to SPF failures.

January 2025 - MXToolbox Blog
Marketer view

Marketer from Email Geeks answers stating that it is a false positive on the Google side.

January 2025 - Email Geeks
Marketer view

Email marketer from Mailjet Blog responds that a drop could be the result of a phishing attack where someone is spoofing your domain. In this case, you should setup more stringent DMARC policies.

November 2024 - Mailjet Blog
Marketer view

Email marketer from StackExchange shares that a sudden drop can also be due to changes Google makes in how they process SPF, DKIM, and DMARC. However you should investigate this first to ensure you have no misconfigurations before blaming external forces.

December 2023 - StackExchange
Marketer view

Email marketer from Neil Patel's Blog shares that issues with SPF records reported in Gmail Postmaster Tools can stem from exceeding the DNS lookup limit. He advises to flatten the SPF record to stay within the limit.

June 2024 - Neil Patel's Blog
Marketer view

Marketer from Email Geeks responds confirming the issue is still happening.

October 2022 - Email Geeks
Marketer view

Email marketer from ReturnPath Blog (now Validity) shares that inconsistent SPF record implementations can cause temporary drops in recognition, and advises regularly testing and updating your SPF records with all valid senders to avoid deliverability issues.

November 2024 - ReturnPath Blog (now Validity)
Marketer view

Email marketer from Email Marketing Forum responds stating a drop in SPF records could mean a new sending source isn't authenticated or an existing one is failing authentication. It could also mean a third party is sending emails on your behalf.

June 2024 - Email Marketing Forum

What the experts say
2Expert opinions

Experts suggest that a sudden drop in SPF records reported by Gmail Postmaster Tools can stem from issues related to your sending infrastructure, potentially indicating unauthorized use of your domain for sending spam. It could also be a consequence of Gmail's aggressive filtering practices, especially when unexpected shifts in email traffic sources are detected. Therefore, a thorough examination of your sending practices and infrastructure is crucial.

Key opinions

  • Unauthorized Use: Drop in SPF pass rates may indicate unauthorized use of your domain for spamming.
  • Infrastructure Problem: Points to underlying issues related to the sending infrastructure.
  • Aggressive Filtering: Could be due to Gmail's aggressive filtering practices.
  • Traffic Shifts: Gmail might be detecting unexpected shifts in email traffic sources.

Key considerations

  • Examine Infrastructure: Thoroughly examine the sending infrastructure for potential problems.
  • Assess Sending Practices: Re-evaluate your sending practices, especially in response to traffic source changes.
  • Check for Unauthorized Use: Investigate whether your domain is being used for unauthorized spam activity.
  • Monitor Traffic Patterns: Monitor your email traffic patterns to identify unexpected shifts or anomalies.
Expert view

Expert from Spam Resource explains that a sudden drop in SPF pass rates can indicate a problem with your sending infrastructure, potentially due to unauthorized use of your domain to send spam which would cause SPF failures.

May 2023 - Spam Resource
Expert view

Expert from Word to the Wise shares that sudden changes in SPF results within Gmail Postmaster Tools could be due to aggressive filtering practices, particularly if Gmail detects unexpected shifts in the source of your email traffic, requiring a thorough examination of your sending practices.

February 2023 - Word to the Wise

What the documentation says
5Technical articles

Documentation from multiple sources indicates that a sudden drop in SPF records in Gmail Postmaster Tools suggests an issue with email authentication. This could mean a higher percentage of your emails are failing SPF checks, potentially due to incorrect DNS records or a lack of authorized sending IPs. A drop could also indicate DMARC alignment issues when SPF is the primary authentication method. Furthermore, it might signify your domain is being spoofed by malicious senders. Therefore, an immediate email authentication audit is essential to identify gaps in your strategy and ensure compliance with email standards.

Key findings

  • Increased SPF Failures: A larger percentage of emails are failing SPF checks.
  • Incorrect DNS Records: There are likely issues with DNS records.
  • Missing Authorized IPs: Authorized sending IPs may not be correctly listed.
  • DMARC Alignment Issues: There may be problems with DMARC alignment.
  • Domain Spoofing: Your domain might be targeted by spoofing attacks.

Key considerations

  • Check Authentication Setup: Review your email authentication setup and DNS records.
  • Audit SPF Records: Routinely audit SPF records to ensure authorized sending IPs are listed.
  • Ensure DMARC Alignment: Ensure proper DMARC alignment, especially when relying on SPF.
  • Email Authentication Audit: Conduct an email authentication audit to identify potential gaps.
  • Ensure Compliance: Ensure compliance with email standards to prevent spoofing and phishing.
Technical article

Documentation from Google Support explains that a decrease in SPF pass rate, as seen in Postmaster Tools, typically suggests that a larger percentage of your email is failing SPF checks, and to check your authentication setup and DNS records.

March 2022 - Google Support
Technical article

Documentation from DMARC.org answers that a sudden drop might also indicate an issue with DMARC alignment if SPF is used as the primary authentication method. Without proper alignment, messages may fail DMARC checks even with a passing SPF result.

June 2024 - DMARC.org
Technical article

Documentation from Microsoft Docs explains the importance of routinely auditing your SPF records, specifically when a drop is detected, to ensure your authorized sending IPs are correctly listed. If not, legitimate emails may fail authentication.

July 2023 - Microsoft Docs
Technical article

Documentation from RFC Editor explains that a sudden SPF drop may indicate that your domain is being spoofed by malicious senders who are not authorized to send on your behalf and whose emails are failing the SPF check.

November 2022 - RFC Editor
Technical article

Documentation from Valimail explains that a sudden decrease in SPF pass rate can signify an urgent need for an email authentication audit to identify potential gaps in your strategy, and ensure compliance with email standards to prevent spoofing and phishing.

August 2024 - Valimail