How can you confirm if an update is algorithmic or policy-based?
Still have a question, spotted an error, or have a better explanation or a source we should cite?
When your deliverability suddenly shifts, the first question is always. Is this a rule change or did their algorithm tweak. Here's how you figure it out.
Check provider announcements first. Policy changes get announced. Mailbox providers publish changelogs, blog posts, or postmaster tool alerts when they enforce new rules. Algorithmic changes usually don't. If you can't find an official announcement, it's probably algorithmic.
Look for uniform impact. Policy changes hit everyone the same way. If you're at 0.25% complaint rate and the threshold is 0.3%, you shouldn't be filtered. But if your mail is landing in spam anyway, that's algorithmic (probably based on engagement, sender history, or content matching).
Test against known criteria. Look up the provider's public requirements or postmaster documentation. Can you pass every stated rule. SPF aligned, DKIM signed, DMARC policy set, List Unsubscribe header present, complaint rate under threshold. If you pass everything and still see problems, that's algorithmic territory.
The key difference for you. Policy issues are binary. you're either compliant or not. Algorithmic issues are gradual and personalized. Some recipients might filter your mail while others don't. Policies affect all similar senders uniformly.
Why does this matter. If it's policy, you can fix it (add SPF, lower complaints, etc.). If it's algorithmic, you're managing perception and engagement. Those are completely different battles.
Check our Review My Emails SOS service if you're stuck diagnosing which one you're facing. We'll decode what changed and why.
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