Outlook Promotions tag checker

Did Microsoft 365 tag your email as Promotions? Paste the headers of a message you sent to a Microsoft 365 business mailbox. You'll see whether Outlook tagged it, its bulk complaint level (BCL), the spam verdict, and what to change.

How to copy the headers

1. Send your email to a Microsoft 365 mailbox in another organization. Mail from a tenant's own domains is never tagged.
2. Open the message in Outlook on the web or the new Outlook for Windows. Click … (More actions) → View → View message details, select all and copy.
3. Classic Outlook: open the message, then File → Properties → Internet headers.

Pasted headers are read in memory and discarded. Nothing is saved.

What the checker looks for

• X-MS-Exchange-Organization-BulkCategory: Promotions: in our test on a Microsoft 365 Business Premium mailbox, every tagged message had this header and untagged messages didn't. Microsoft doesn't document it.
• BCL: in X-Microsoft-Antispam: the bulk complaint level, 0 to 9. The default anti-spam policy sends 7 and higher to Junk Email.
• SCL, SFV and CAT in X-Forefront-Antispam-Report: the spam verdict. A tagged message can still be "not spam" and land in the Inbox.
• SPF, DKIM and DMARC results and the unsubscribe headers. They don't remove the tag, but every bulk sender needs them.

Who is affected, the dates, what we saw in our test and how to reduce tagging: Outlook Promotions tag in Microsoft 365: what senders can do.