What information can I get from Microsoft SNDS?

Microsoft's Smart Network Data Services (SNDS) is the Outlook and Microsoft 365 equivalent of Google Postmaster Tools. It shows you daily data about your sending IP's reputation as Microsoft's systems see it. If a significant portion of your list uses Outlook, Hotmail, or Microsoft 365 addresses, SNDS is worth checking regularly.

What SNDS shows you

IP status. A color-coded reputation indicator for each of your sending IPs: green (good), yellow (caution), red (blocked). Red means Microsoft is filtering your email aggressively. Yellow is a warning to pay attention.

Complaint counts. The number of times Microsoft users reported your IP's email as spam over the reporting period. Unlike Google's spam rate percentage, this is a raw count. High complaint counts relative to your sending volume are a problem even if the individual numbers look small.

Spam trap hits. Whether your IP has hit any of Microsoft's spam traps during the reporting period. Any trap hits at all are worth investigating. Multiple trap hits per reporting cycle suggest serious list hygiene problems.

Traffic volume. Total messages sent from each IP. Useful for calculating complaint rates yourself and for understanding whether your sending patterns look normal to Microsoft.

What SNDS doesn't show

SNDS doesn't give you domain-level data the way Google Postmaster Tools does. It's IP-focused. If you're on a shared IP, the data reflects the whole pool, not just your sending. That limits how much you can act on individual metrics unless you're on a dedicated IP or working with your ESP to understand your share of the pool.

If you haven't set up SNDS yet, the process is quick. You verify IP ownership and Microsoft provides access to daily data going back 90 days. For step-by-step setup, see the SNDS signup guide.

Still if your SNDS numbers look bad and you're not sure what to do, our blocklist checker covers Microsoft's blocklists and can show you if you've been listed.