Substack incident

Issue with reported open rates

Resolved after 44 days 19 hours, affecting Email delivery, on March 27, 2026.

investigating Mar 27, 2026, 10:20 PM UTC

We’re investigating an issue affecting reported open rates for some publishers. Current evidence suggests this is related to how Gmail loads tracking pixels, and does not indicate a change in engagement or deliverability. We take responsibility for ensuring these metrics are accurate and are prioritizing improvements to our open rate tracking so this is resolved as quickly as possible. We will continue to provide updates here as we learn more.

Started
Mar 27, 2026, 10:20 PM UTC
Resolved
May 11, 2026, 05:55 PM UTC
Duration
44d 19h
Detected by Pingoru
Mar 27, 2026, 10:20 PM UTC

Affected components

Email delivery

Update timeline

  1. investigating Mar 27, 2026, 10:20 PM UTC

    We’re investigating an issue affecting reported open rates for some publishers. Current evidence suggests this is related to how Gmail loads tracking pixels, and does not indicate a change in engagement or deliverability. We take responsibility for ensuring these metrics are accurate and are prioritizing improvements to our open rate tracking so this is resolved as quickly as possible. We will continue to provide updates here as we learn more.

  2. resolved May 11, 2026, 05:55 PM UTC

    This incident has been resolved.

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