One hosting account can run email for every domain you host on it, not just the primary one. Each domain gets its own set of mailboxes, and mail for you@domain-a.com stays separate from you@domain-b.com, as long as each domain's DNS points its MX records at your hosting.
How it works
Go to Services, click your hosting, and open Email Accounts. If a second domain is hosted as an addon domain on the same account, it appears there too, and you can create mailboxes on it with the same New mailbox button you'd use on the primary domain. See Creating email accounts on your domain for the exact steps.
Each domain's mailboxes are independent. info@domain-a.com and info@domain-b.com can exist on the same account with different passwords, different storage quotas, and separate inboxes. There's no cross-domain aliasing unless you set up a forwarder.
Adding a domain for email
If the second domain isn't attached to your hosting account yet, it needs to be added as an addon domain first (from Services → your hosting → Addon Domains). Once it's attached, its DNS is either managed by us (if you pointed its nameservers at ours) or you'll need to add matching MX records yourself in that domain's own DNS provider.
For domains whose DNS we manage, mail records can be added in Services → your hosting → DNS Zone Editor. If you're troubleshooting mail flow for a specific domain, confirm its MX records point at your hosting and haven't been overridden, for example by a partial migration to Google Workspace on just one domain.
Keeping domains distinct in day-to-day use
A few habits make multi-domain email manageable:
- Use the one-click Webmail login from Services, or bookmark Roundcube separately per domain, so you always know which mailbox you're looking at.
- In a desktop or mobile email client, add each address as a separate account rather than an alias of one account. The full email address is the username for IMAP/SMTP, so each domain's mailboxes authenticate independently anyway.
- If a brand is more than a placeholder domain and you expect ongoing volume from it, set up DKIM signing and SPF for that domain specifically. Authentication records are per-domain, so a second domain doesn't inherit the first domain's reputation or setup automatically, even though both live on the same hosting account.
Storage and limits
Mailbox storage draws from your hosting account's overall disk usage, so mailboxes on one domain aren't walled off from mailboxes on another. Keep an eye on total usage across all domains rather than assuming each one has a separate allowance.
Each plan has an addon-domain allowance (25 on the Start plan), and the usage counters on your service page show how many you have used. If you're not sure, open a ticket and ask.
Backing it up
Backups run nightly, are encrypted, and are verified daily, covering the files, accounts, and databases on your hosting. If you want your own archive of a specific domain's mail, the options in backing up your email: IMAP local copies, webmail export, or a cPanel Backup Wizard download, work the same regardless of which domain the mailboxes belong to.
When to contact support
If a second domain isn't showing up under Email Accounts, or mail is bouncing after you've confirmed MX records are correct, open a ticket from Support in the portal. A real person will check the addon domain configuration and DNS zone directly rather than have you guess at it.