Study: Self-Hosted Email Keeps Shrinking as Google and Microsoft Dominate
A new analysis of MX records across the Tranco top one million domains finds that self-hosted email continues its long decline. Google Workspace and Microsoft 365 now handle mail for a dominant share of active domains, while the remainder is split among a shrinking pool of smaller providers and a long tail of domains still running their own mail servers.
The researcher describes a 'stubborn plateau' - a persistent but shrinking minority of organizations that continue to self-host, likely for compliance, cost, or control reasons. Everyone else has consolidated onto the two major platforms, continuing a trend that has played out for over a decade as spam filtering, deliverability, and security demands made running your own mail server increasingly painful.
The data adds hard numbers to something sysadmins have felt anecdotally for years: self-hosted email is now a niche practice rather than a default choice.