How many companies use Microsoft 365?

TechLeads currently detects Microsoft 365 on 2,701,100 websites. HTTP Archive's monthly crawl, a separate dataset, detected it on 6,889,878 pages in September 2026.

Who are Microsoft 365's biggest competitors?

By number of websites, the largest Email technologies besides Microsoft 365 are Google Workspace (3,246,665), Hostinger Mail (938,104), MailChimp (820,056), IONOS Mail (690,910), Mailgun (664,476).

Which companies use Microsoft 365?

Websites using Microsoft 365 include disqus.com, apnews.com, zenodo.org, duckduckgo.com, nps.gov, variety.com. The full list of 2,701,100 websites can be exported as a CSV for $29.

Microsoft 365 market share and customers

As of October 8, 2026, Microsoft 365 is used by 2,701,100 websites in the TechLeads index: 21.7% of all Email detections, the 2nd most-used of 133 Email technologies.

2,701,100

websites using Microsoft 365

21.7%

share of Email

of 133 in Email

Cite this data

Quoting these numbers? Credit TechLeads with a link to this page.

Citation

TechLeads. "Microsoft 365 Customers and Market Share." Data as of October 8, 2026. https://techleads.fyi/technology/microsoft-365/market-share

HTML link

<a href="https://techleads.fyi/technology/microsoft-365/market-share">Microsoft 365 market share (TechLeads data)</a>

Microsoft 365 vs competitors in Email

Websites using each technology in the TechLeads index, and its share of all Email detections.

#	Technology	Websites	Share
1	Google Workspace	3,246,665	26.1%
2	Microsoft 365	2,701,100	21.7%
3	Hostinger Mail	938,104	7.6%
4	MailChimp	820,056	6.6%
5	IONOS Mail	690,910	5.6%
6	Mailgun	664,476	5.3%
7	Amazon SES	634,305

Microsoft 365 usage over time

In HTTP Archive's monthly crawl of public websites, Microsoft 365 was detected on 6,889,878 pages in September 2026, up 0.46% from a year earlier (peak: 7,301,172). Among the 1,000 most-visited sites, it appeared on 208. HTTP Archive is a separate dataset from the TechLeads index, so its numbers are not added to ours.

Same month, other Email technologies in HTTP Archive: Google Workspace 7,328,416, MailChimp 1,572,197, Sendgrid 1,280,135, Amazon SES 1,270,273, Mailgun 1,186,643.

Microsoft 365 customers by country

Based on country-code domains (such as .de or .co.uk); websites on .com and other generic domains are not assigned a country.

US22,449
GB8,948
DE4,139
FR3,223
AU2,576
CA1,983
NL1,441
CH1,210
IT1,182
BR911

Companies using Microsoft 365

disqus.com
apnews.com · AP News
zenodo.org
duckduckgo.com
nps.gov
variety.com · Variety Australia
south-ayrshire.gov.uk · South Ayrshire Council
kerrymuseum.ie · Kerrymuseum
wmrt.com · World Match Racing Tour
adobe.com
autotrader.co.uk
bing.com · Search - Microsoft Bing

See all 2,701,100 websites using Microsoft 365 or download the full list as a CSV for $29.

How these numbers are calculated

TechLeads scans public websites and detects Microsoft 365 from signals in the page HTML, scripts, cookies, HTTP headers and DNS records. Market share is Microsoft 365's website count divided by the website counts of all Email technologies we track; a site using two Email tools counts for both. Counts were last refreshed on October 8, 2026 and update daily.

FAQ

Microsoft 365 accounts for 21.7% of Email detections in the TechLeads index (2,701,100 websites), which makes it the 2nd most-used of 133 Email technologies we track.