Use a subdomain, unless you really mean it
23 July 2026 · 3 min read
MX records are per hostname. Setting an MX on example.com routes every message for that domain to the new destination. Setting one on alias.example.com routes only that subdomain and leaves the parent untouched.
When the subdomain is right
- You already receive mail on the domain.
- You are trying a service out.
- You want to keep the two flows separable later.
When the apex is right
When the new service genuinely is your mail provider, and you have moved everything else first.
Addresses on a subdomain look slightly longer and work identically. That is the entire downside.
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