How to set up email forwarding for a custom domain

If you own a domain (e.g. yourdomain.com), you can route all incoming email through Cleanbox. This gives you aliases on your own domain, full spam filtering, and centralized management — without running your own mail server.

Overview

There are two ways to handle email on a custom domain with Cleanbox, depending on whether you already have a mail server:

	Aliases (IMAP)	Relay (SMTP forward)
You have a mail server	No	Yes
How email is delivered	IMAP upload to Gmail, Outlook, etc.	SMTP forward to your server
Creates new addresses	Yes	No — protects existing ones
Minimum plan	Premium	Advanced

Option 1: Aliases on your domain (no mail server needed)

This is the simplest setup. You create aliases like shop@yourdomain.com or info@yourdomain.com and Cleanbox forwards them to your existing mailbox (Gmail, Outlook, iCloud, etc.) via IMAP.

Step-by-step setup

1. Add your domain — Go to Domains → Add domain → Enter yourdomain.com
2. Add DNS records at your DNS provider:
   • MX record: @ → mx1.cleanbox.to (priority 10)
   • TXT record: @ → cleanbox-verify=your-token
   • SPF record: Add include:_spf.cleanbox.to to your existing SPF, or create: v=spf1 include:_spf.cleanbox.to ~all
3. Verify — Click "Verify" in Cleanbox. Wait for DNS propagation if needed (usually 5–15 minutes).
4. Create aliases — Go to Aliases → Add alias → Select your domain → Enter the local part (e.g. info)
5. Select a mailbox — Choose which connected mailbox receives the forwarded emails

That is it. Emails sent to info@yourdomain.com are now filtered by Cleanbox and delivered to your mailbox.

Important notes

• Remove old MX records — If your domain previously pointed to another mail provider, remove those MX records. Otherwise email will be split between providers unpredictably.
• Only listed aliases receive mail — Cleanbox does not accept email for addresses that are not configured. If someone emails random@yourdomain.com and no alias exists, the email bounces.

Option 2: Relay (you have your own mail server)

If you already run a mail server (or use Google Workspace / Microsoft 365) and want to keep your existing addresses, use Relay. Cleanbox sits in front of your server as a spam filter.

Step-by-step setup

1. Add and verify your domain (same DNS steps as above)
2. Enable Relay — Go to your domain → Relay tab → Enable
3. Configure SMTP destination — Enter your mail server hostname and port (e.g. mail.yourdomain.com:25)
4. Add relay addresses — Specify which addresses to protect (e.g. info@yourdomain.com, support@yourdomain.com)
5. Test — Click "Test relay" to verify Cleanbox can reach your server
6. Update MX records — Point MX to mx1.cleanbox.to (remove or lower priority of old MX records)

How it differs

• Cleanbox filters inbound email, then forwards via SMTP to your server
• Your existing addresses keep working — no migration needed
• Your outbound email (SPF, DKIM, DMARC) is completely untouched
• Includes ClamAV virus scanning
• If SMTP forwarding fails, messages are queued and retried automatically

Which option should you choose?

• Choose aliases if you do not run a mail server and want to create new forwarding addresses on your domain.
• Choose relay if you already have working email on the domain and want to add spam filtering without changing how your mail works.
• Use both on the same domain if you want aliases for new addresses AND relay protection for existing ones (Advanced/Enterprise plans).

For detailed DNS setup instructions, see DNS configuration: MX, TXT, and SPF records.