How does Microsoft interpret engagement?

You've probably noticed that Outlook behaves differently from Gmail. Your open rates for Microsoft recipients might look fine on paper, but emails still end up in Junk. That's because Microsoft's engagement model has a few quirks worth understanding.

The positive signals Microsoft watches: opens, clicks, replies, forwards, and whether someone moves your email to a specific folder. Speed matters too. If a recipient tends to open your emails quickly after delivery, that's a strong positive signal. Slow or no interaction? That works against you.

The negative signals carry serious weight. A user marking your email as junk is the obvious one. But Microsoft also notices when someone deletes your email without opening it, or consistently scrolls past it without any interaction. The Focused Inbox algorithm learns from these patterns at the individual user level. A subscriber who never opens your emails trains their own inbox to deprioritize you, even if your overall reputation is healthy.

One important distinction: Microsoft's consumer filtering (Outlook.com) and its corporate filtering through Microsoft 365 and Exchange Online Protection work differently. Consumer inboxes apply engagement signals more personally. Corporate inboxes sit behind stricter IT-controlled policies where individual engagement plays less of a role. If your Microsoft deliverability issues are concentrated in certain company domains, that's often a corporate filter problem, not a personal engagement problem.

Compared to Gmail's highly personalized engagement model, Microsoft's consumer filtering applies engagement data a bit more broadly across your recipient base. Your aggregate engagement rates across all Microsoft recipients shape your sender reputation there. Individual training still affects each person's inbox, but your overall numbers set the baseline.

What this means for you practically:

• Segment out Microsoft recipients who haven't opened in 90 days. Continuing to send to them drags down your reputation with Microsoft specifically.
• Watch your Microsoft-specific engagement metrics separately in your SNDS and JMRP data. They'll tell you more than your ESP dashboard will.
• If you're seeing Junk placement rather than outright blocks, engagement re-warming is often the fix. Slow down volume, target only your most active Microsoft recipients, and let positive signals rebuild before expanding.

If your Microsoft delivery has gone sideways and you're not sure where to start, our SOS hotline is free. No pitch, just help.