# The most used email and workspace providers As of October 2026, the most used of the 21 email and workspace providers runsonwhat tracks is Microsoft 365, found at 694,528 companies, ahead of Google Workspace (393,366) and Apple Business (109,413). Almost every company with its own domain runs its mailboxes on Google Workspace or Microsoft 365. Microsoft leads at larger and older companies; Google Workspace leads at startups and smaller firms. Privacy-focused providers (Proton Mail, Fastmail, Tuta) and regional ones (Tencent Exmail, VK WorkSpace) make up most of the rest. ## Email and workspace providers ranked by companies using them | # | Tool | Companies | Share of category | Last 30 days | Most popular with | |---|---|---|---|---|---| | 1 | [Microsoft 365](https://www.runsonwhat.com/reverse/microsoft-365) | 694,528 | 55% | +90 −16 | 1,001–5,000 employees (1.4×) | | 2 | [Google Workspace](https://www.runsonwhat.com/reverse/google-workspace) | 393,366 | 31% | +53 −5 | Internet (1.6×) | | 3 | [Apple Business](https://www.runsonwhat.com/reverse/apple) | 109,413 | 8.6% | +91 −14 | 1,001–5,000 employees (3.0×) | | 4 | [Exclaimer](https://www.runsonwhat.com/reverse/exclaimer) | 34,555 | 2.7% | +859 −1 | Construction (2.7×) | | 5 | [Tencent Exmail](https://www.runsonwhat.com/reverse/tencent-exmail) | 6,402 | 0.50% | +53 | Electrical/electronic Manufacturing (5.3×) | | 6 | [Rackspace Email](https://www.runsonwhat.com/reverse/rackspace-email) | 6,090 | 0.48% | +26 | Restaurants (3.6×) | | 7 | [Yandex 360](https://www.runsonwhat.com/reverse/yandex-360) | 5,943 | 0.47% | +55 | Internet (2.4×) | | 8 | [Titan](https://www.runsonwhat.com/reverse/titan-email) | 4,624 | 0.36% | +15 | Marketing and Advertising (2.0×) | | 9 | [NetEase Qiye Mail](https://www.runsonwhat.com/reverse/netease-qiye) | 3,190 | 0.25% | +27 | Electrical/electronic Manufacturing (8.3×) | | 10 | [Proton Mail](https://www.runsonwhat.com/reverse/proton) | 2,416 | 0.19% | +2 | 1–10 employees (3.1×) | | 11 | [OpenSRS Hosted Email](https://www.runsonwhat.com/reverse/opensrs-email) | 1,914 | 0.15% | – | Restaurants (3.4×) | | 12 | [VK WorkSpace](https://www.runsonwhat.com/reverse/vk-workspace) | 1,699 | 0.13% | +38 | Internet (2.0×) | | 13 | [Fastmail](https://www.runsonwhat.com/reverse/fastmail) | 1,100 | <0.1% | +3 | 1–10 employees (5.5×) | | 14 | [Signature 365](https://www.runsonwhat.com/reverse/signature-365) | 995 | <0.1% | +30 | Construction (3.7×) | | 15 | [iCloud Mail](https://www.runsonwhat.com/reverse/icloud-mail) | 903 | <0.1% | +76 | 1–10 employees (2.4×) | | 16 | [LINE WORKS](https://www.runsonwhat.com/reverse/line-works) | 399 | <0.1% | +15 | IT Services (2.1×) | | 17 | [Migadu](https://www.runsonwhat.com/reverse/migadu) | 382 | <0.1% | +9 | Software (2.0×) | | 18 | [mailbox.org](https://www.runsonwhat.com/reverse/mailbox-org) | 295 | <0.1% | +16 | Retail (2.4×) | | 19 | [Purelymail](https://www.runsonwhat.com/reverse/purelymail) | 224 | <0.1% | +41 | IT Services (1.9×) | | 20 | [Tuta](https://www.runsonwhat.com/reverse/tuta) | 53 | <0.1% | +2 | – | | 21 | [HEY](https://www.runsonwhat.com/reverse/hey-email) | 47 | <0.1% | – | – | Share is each tool's part of all 1,268,538 matches in this category; a company using two tools counts for both. ## How to compare email and workspace providers - The office suite your team already uses (Docs and Sheets, or Word and Excel). - Identity: Microsoft Entra ID or Google accounts as the company directory. - Security and compliance add-ons included in each plan. - Price per user at the tier that includes the features you need. ## How runsonwhat finds email and workspace providers The mail provider is named directly by a domain's MX records, and confirmed by SPF includes, DKIM keys and verification TXT records. ## FAQ ### What are the most popular email and workspace providers? As of October 2026, the most popular email and workspace providers by number of companies using them are Microsoft 365 (694,528 companies), Google Workspace (393,366 companies) and Apple Business (109,413 companies), according to runsonwhat. Microsoft 365 alone accounts for 55% of the 1,268,538 Workspace matches runsonwhat has, and the top three together for 94%. 21 email and workspace providers have at least one confirmed customer. ### Microsoft 365 vs Google Workspace: which is more popular? Microsoft 365 is more popular: 694,528 companies show public evidence of Microsoft 365, against 393,366 for Google Workspace (1.8× as many), according to runsonwhat (October 2026). Apple Business is third with 109,413. ### Which email and workspace providers do small businesses use most? Among companies with up to 50 employees, the most used email and workspace providers are Microsoft 365 (341,900 companies), Google Workspace (236,480 companies) and Apple Business (31,486 companies), according to runsonwhat (October 2026). The counts cover companies with a known headcount; see each tool's page for the full size breakdown. ### Which email and workspace providers do large companies use most? Among companies with more than 1,000 employees, the most used email and workspace providers are Microsoft 365 (34,845 companies), Apple Business (11,133 companies) and Google Workspace (9,666 companies), according to runsonwhat (October 2026). Large companies often run more than one tool in a category, so the same company can count for several. ### Which email and workspace providers are most popular in the United States? In the United States, the most used email and workspace providers are Microsoft 365 (213,428 companies), Google Workspace (127,601 companies) and Apple Business (42,780 companies), based on companies runsonwhat has located there (October 2026). Microsoft 365 has 53% of the Workspace matches among companies based in the United States. ### Which email and workspace providers are most popular in the United Kingdom? In the United Kingdom, the most used email and workspace providers are Microsoft 365 (54,372 companies), Google Workspace (16,685 companies) and Apple Business (8,537 companies), based on companies runsonwhat has located there (October 2026). Microsoft 365 has 63% of the Workspace matches among companies based in the United Kingdom. ### Which email and workspace providers do IT services companies use? IT services is the industry with the most Workspace matches, and its companies use Microsoft 365 (61,164 companies), Google Workspace (35,356 companies) and Apple Business (7,868 companies) most, according to runsonwhat (October 2026). Each tool's page breaks its customers down by industry, so you can check where a tool over-indexes. ### Which email and workspace providers are companies adopting right now? In the 30 days to October 2026, the most new adoptions runsonwhat recorded were for Exclaimer (859 companies), Apple Business (91 companies) and Microsoft 365 (90 companies). A start is counted when a recheck finds a tool that the previous check of the same company, done the same way, did not. ### What is Microsoft 365's market share among email and workspace providers? Microsoft 365 has 55% of the Workspace matches runsonwhat has found (694,528 companies of 1,268,538), as of October 2026; Google Workspace has 31%. This is share of companies with public evidence of each tool, not share of revenue or seats, and a company that runs two tools counts for both. ### How does runsonwhat rank email and workspace providers? runsonwhat counts the companies where a public record shows each tool in use and ranks by that count. The mail provider is named directly by a domain's MX records, and confirmed by SPF includes, DKIM keys and verification TXT records. A company counts only when a direct record backs it up. The full method is at https://www.runsonwhat.com/methodology. ## Related categories - [Email Delivery](https://www.runsonwhat.com/tools/email-delivery.md) - [Collaboration](https://www.runsonwhat.com/tools/collaboration.md) - [Dev Tools](https://www.runsonwhat.com/tools/developer-tools.md) - [People & HR](https://www.runsonwhat.com/tools/hr-recruiting.md) - [Finance & Legal](https://www.runsonwhat.com/tools/finance-legal.md) - [Security & Compliance](https://www.runsonwhat.com/tools/security-compliance.md) --- Source: runsonwhat, https://www.runsonwhat.com/tools/email-workspace (updated October 2026). Counts are companies with direct public evidence of the tool (DNS records, certificates, website code, a real-browser crawl, subprocessor lists), so they are lower bounds. Methodology: https://www.runsonwhat.com/methodology.