Microsoft Federal Tax ID, W-9 and DUNS Info

Microsoft's federal tax ID is 91-1144442. Should you require a W-9 form from Microsoft, email the Microsoft Ignite registration team at with subject line, "ATTN: FINANCE, W-9 Request."

The Microsoft DUNS number is 08-146-6849.

If you are not attending Microsoft Ignite but are seeking a W-9 for purchases made at a Microsoft Store, contact for assistance.

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