As of October 11, 2026, Microsoft Exchange Online is used by 3,567,170 websites in the TechLeads index: 45.1% of all Business Email Hosting detections, the 2nd most-used of 46 Business Email Hosting technologies.
Quoting these numbers? Credit TechLeads with a link to this page.
Citation
TechLeads. "Microsoft Exchange Online Customers and Market Share." Data as of October 11, 2026. https://techleads.fyi/technology/microsoft-exchange-online/market-shareHTML link
<a href="https://techleads.fyi/technology/microsoft-exchange-online/market-share">Microsoft Exchange Online market share (TechLeads data)</a>Websites using each technology in the TechLeads index, and its share of all Business Email Hosting detections.
| # | Technology | Websites | Share |
|---|---|---|---|
| 1 | Office 365 Mail | 3,817,196 | 48.3% |
| 2 | Microsoft Exchange Online | 3,567,170 | 45.1% |
| 3 | Titan Email | 202,239 | 2.6% |
| 4 | Proton Mail | 105,300 | 1.3% |
| 5 | Namecheap Private Email | 83,016 | 1.1% |
| 6 | Mimecast | 38,769 | 0.49% |
| 7 | SpamExperts |
Based on country-code domains (such as .de or .co.uk); websites on .com and other generic domains are not assigned a country.
See all 3,567,170 websites using Microsoft Exchange Online or download the full list as a CSV for $29.
TechLeads scans public websites and detects Microsoft Exchange Online from signals in the page HTML, scripts, cookies, HTTP headers and DNS records. Market share is Microsoft Exchange Online's website count divided by the website counts of all Business Email Hosting technologies we track; a site using two Business Email Hosting tools counts for both. Counts were last refreshed on October 11, 2026 and update daily.
| 34,737 |
| 0.44% |
| 8 | Zoho Mail | 22,987 | 0.29% |
| 9 | SpaceMail | 6,452 | 0.08% |
| 10 | Zimbra | 4,428 | 0.06% |
| 11 | Skymail | 4,042 | 0.05% |
| 12 | Everyone.net | 3,923 | 0.05% |
| 13 | Securence | 2,558 | 0.03% |
| 14 | Migadu | 2,295 | 0.03% |
| 15 | Mailcheap | 2,078 | 0.03% |
| 16 | BlueTie | 1,929 | 0.02% |
| 17 | Spam Hero | 1,534 | 0.02% |
| 18 | postale.io | 1,016 | 0.01% |
| 19 | Exclaimer | 955 | 0.01% |
| 20 | Pobox | 578 | 0.01% |
| 21 | MX-Relay | 555 | 0.01% |
Rows link to each competitor's market share page where one exists. The table lists the 21 most-used technologies; ranks are by website count.