MX records tell the internet where to deliver email for a domain. Priority values rank mail servers: lower numbers are tried first. Use multiple MX records for redundancy, keep the hostnames correct, and verify with DNS lookups. Wrong MX priority or missing records commonly causes bounced or delayed email.
What Is MX Priority
MX (Mail Exchange) records specify which servers handle email for your domain. Each record has two components: a hostname pointing to the mail server and a priority number.
Priority determines contact order. Lower numbers mean higher priority, a server with priority 1 is tried before priority 10. If primary is unavailable, sending servers try the next level.
Think of it as preference ranking: 1 is most preferred, 10 is less preferred, 50 is backup only. We recommend starting with priority 1 rather than 0 for cleaner configuration.
Primary vs Backup Servers
Most providers supply multiple MX records for redundancy:
Multiple servers at the same priority receive distributed traffic. If you only have one mail server, a single MX record works, but enterprise providers use multiple records for reliability.
Adding MX Records in NameSilo
Navigate to Domain Manager, click the blue globe icon ( 🌎) next to your domain to open DNS Manager. Add MX records with:
- Host: Leave blank or enter “@”
- Mail Server: Hostname from your email provider
- Priority: Number your provider specifies
- TTL: 3600 seconds minimum
Add each MX record separately.
Common Email Provider Setups
| |
| yourdomain-com.mail.protection.outlook.com |
(Replace "yourdomain-com" with your actual domain, substituting hyphens for dots)
Always use exact hostnames, typos cause delivery failures.
Common Mistakes: MX Pointing to IP Addresses
MX records must point to hostnames, not IP addresses. This is a protocol requirement.
Wrong: MX pointing to 192.168.1.1
Correct: MX pointing to mail.yourdomain.com (with an A record resolving to the IP)
Other mistakes: forgetting trailing periods in some DNS interfaces, conflicting priorities, and leaving old MX records pointing to decommissioned servers.
What This Means for You
NameSilo offers one-click email setup templates for popular providers. Select your provider and we populate the correct MX configuration automatically.
For custom setups, DNS Manager gives full control over priorities and hostnames. After adding records, verify MX resolution with lookup tools before expecting delivery.
Frequently Asked Questions
What does MX priority mean?Â
Priority ranks mail servers by preference. Sending servers try lower numbers first, moving higher if earlier servers are unavailable.
Why are lower numbers higher priority?Â
It's a preference scale, 1 means "try first," 50 means "try last." This convention comes from early email standards.
Should I use multiple MX records?Â
Yes for redundancy. Multiple records ensure delivery even if one server has issues.
How do I find my current MX records?Â
Use DNS lookup tools or check DNS Manager. Search "MX lookup" and enter your domain.
What's the difference between MX and A records?Â
MX specifies mail servers. A records map hostnames to IPs. MX points to a hostname needing its own A record.
Why are emails bouncing after a change?Â
Common causes: typos in hostnames, missing records, or propagation delays. Verify records match provider specs.
How long do MX changes take to work?Â
Typically hours, up to 48 for full propagation. TTL affects caching duration.
What MX setup do Google Workspace/Microsoft 365/Titan use?Â
See Common Scenarios above. Each provider publishes specific records in setup documentation.