Email Consolidates Around Google and Microsoft as Self-Hosting Declines
Self hosted email continues to steeply decline
Ten years of DNS measurements from the OpenINTEL project reveal that self-hosted email in the Tranco top-1M has dropped from 44.6% in 2016 to 22.4% in 2026, with Google Workspace and Microsoft 365 now handling 38.6% of inbound mail. DMARC adoption has plateaued: only 46.9% of domains enforce policies, and the most common record is a copy-pasted 'p=none'. A long tail of 36,455 unmatched MX hostnames highlights the invisible infrastructure behind the major providers.
When more than a third of popular domains depend on two providers to receive mail, an outage, a filtering change or a policy decision at either one propagates through the whole ecosystem at once.