MX (mail exchanger) records tell the world which servers receive email for your domain. If they are missing or wrong, you stop receiving mail — while sending often keeps working, which makes the problem easy to miss.
How MX records work
Each MX record has a priority and a host name. Senders try the lowest number first and fall back to higher numbers if it does not answer.
MX · @
10 mx1.provider.com 20 mx2.provider.com
Rules for valid MX records
- Point to a host name, never directly to an IP address
- The host name must have an A or AAAA record — not a CNAME
- Remove MX records of old providers when you migrate
- Use the exact values your email provider gives you
Common provider values
- Google Workspace —
1 smtp.google.com(newer setups; older ones use several aspmx.l.google.com records) - Microsoft 365 —
0 yourdomain-com.mail.protection.outlook.com(shown in the admin center) - Zoho Mail —
mx.zoho.com,mx2.zoho.com,mx3.zoho.com(region-specific)
Always copy the exact values from your provider's admin panel, then confirm with the MX Lookup.
Frequently asked questions
How long do MX changes take?
Usually minutes; at most the TTL of the old records (often 1 hour, sometimes 24).
Can I have MX records from two providers?
Only if both are set up to receive for your domain. Mixing an old and a new provider causes lost mail.
Do MX records affect sending?
Not directly, but some receivers check that your sending domain can receive replies.