MX Record

Why an MX record has to exist

Somebody emails you at yourname@yourcompany.com. Their mail server doesn't know your inbox. It doesn't even know your company. All it has is that domain, and it needs to figure out where messages for it actually land.

That's the entire job of an MX record. It's a line in your domain's DNS settings, basically the internet's directory system, that says, in effect, "mail for this domain goes here." Without it, a sending server has nowhere to deliver to, and the message bounces. Cloudflare's own DNS documentation frames it simply: an MX record points incoming mail to the right mail server, full stop.

Most domains list more than one MX record, each with a priority number attached. Lower numbers go first. So if your domain has a record at priority 1 and another at priority 5, mail tries the first one, and only falls back to the second if that one's unreachable. A built-in backup plan, baked directly into DNS.

But you'll never touch this on a personal Gmail or Outlook address. Whoever manages the actual domain, Google, Microsoft, or your own hosting provider, already handles it. 

When MX records actually come into play

You've got basically one scenario where this becomes your problem: you're setting up email on a domain you own.

Say you're launching yourbusiness.com and want email at that address instead of a free Gmail account. Setting that up means adding an MX record at your domain registrar, pointing to whichever provider you're using. Get it wrong, and mail for your shiny new domain just disappears into nowhere, usually with no bounce notice. It quietly fails.

And switching providers is the other moment this matters. Move from one email host to another, and your MX record has to move with you. Miss that step, and your old provider keeps receiving mail that never makes it to your new inbox.

Setting up an MX record

Who's actually doing this? Usually a business owner, a freelancer, or whoever's wearing the IT hat that week, since it lives at the domain level, not in any inbox app. Here's roughly what it looks like.

For Google Workspace:

• Sign in wherever you registered your domain and find the DNS settings
• Remove any existing MX records that might conflict
• Add a new one: type MX, host left blank or set to @, priority 1, and the value smtp.google.com
• Save, then activate Gmail in the Google Admin console
• Give it time. Google's own documentation says changes can take up to 72 hours to fully propagate

For Microsoft 365:

• In the Microsoft 365 admin center, go to Settings, then Domains, select your domain, and open DNS records
• The setup wizard shows you the exact MX record to add, tailored to your domain, along with any other required records
• Your registrar needs the old provider's MX record removed, or set to a lower priority, so mail doesn't get split between two places

Key information for working with MX records 

Never delete an old MX record before the new one's confirmed working. A gap between the two means lost mail, and you often won't know until someone says they emailed you last week and never heard back.

Give DNS changes real time before troubleshooting. Up to 72 hours is normal. Panicking at hour two just wastes energy on a non-problem.

Keep priority numbers deliberate if you're running more than one mail server. Lower number, higher priority.

Hand this off if it's not your job. If you don't manage your company's domain, this is a five-minute conversation with whoever does, not something to guess at.

Double-check after any provider switch. This is the single most common way businesses accidentally lose incoming mail.

Related terms

• Mail server
• Email domain
• SMTP server
• MTA-STS