A breakdown of the 599 companies running Microsoft Defender for Office 365.
Top industries
Information technology and services257
Financial services79
Professional and business services77
Industrial and manufacturing46
Education and training20
Construction and building17
Art, sports and recreation15
Health and wellness15
No industry recorded: 10
Company size
1–1020 (3%)
11–5037 (6%)
51–25098 (17%)
251–50072 (12%)
501–1,00064 (11%)
1,001–5,000131 (23%)
5,001–10,00040 (7%)
10,001+117 (20%)
Share of companies with a recorded size, by employees.
No size recorded: 20
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Frequently asked questions
About the Microsoft Defender for Office 365 data on this page.
How many companies use Microsoft Defender for Office 365?
Firmable holds confirmed Microsoft Defender for Office 365 detections for 599 distinct companies, 139 of them confirmed in the last 90 days. A company is counted once however many of its properties run it.
Which companies use Microsoft Defender for Office 365?
SC&H Group, THL Partners and ISI are among the most prominent in the current set.
What industries use Microsoft Defender for Office 365?
Information technology and services, financial services and professional and business services lead the set, across 19 industries in total.
What size companies use Microsoft Defender for Office 365?
Adoption concentrates in the 1,001-5,000 employee band, across the companies whose size is recorded.
Where are Microsoft Defender for Office 365 users based?
The United States, Canada, Australia and Singapore account for most detections, across 13 countries.
How current is this data?
139 companies were confirmed in the last 90 days. Last detection 6 September 2026.
