Email forwarding explained
Email forwarding sends messages addressed to your domain on to an inbox you already use. For example, mail to hello@example.com can arrive in your existing personal mailbox. It is a simple way to use an address at your own domain without setting up a new mailbox. This guide explains how forwarding works, how it compares with other options, and the delivery problems to watch for.
Forwarding, mailbox or alias?
| What it does | Stores mail? | Good for | |
|---|---|---|---|
| Forwarder | Passes each incoming message on to another address, such as one at a different provider | No | Receiving mail at your domain in an inbox you already use |
| Mailbox | A full email account with its own storage, password and folders | Yes | Daily business email that you send and receive from your domain |
| Alias | An extra address that delivers into an existing mailbox at the same provider | In the main mailbox | Extra addresses such as sales@ or info@ for one person |
A forwarder can send to more than one destination, which is handy for addresses a small team shares.
How forwarding works
Email for your domain is delivered to the servers named in your domain's MX records (see DNS records explained). To forward mail, those MX records point to a service that offers forwarding. When a message arrives for hello@example.com, that service looks up the forwarding rule and sends the message on to the destination, such as jane@example.net.
This means the MX records must point to the forwarding service, exactly as it specifies. If they point somewhere else, such as an old email provider, the forwarding rules are never used.
A domain has one set of MX records. If you later add mailboxes at a different provider and switch the MX records to it, the forwarding service no longer receives your mail. Recreate any forwarders at the new provider before you switch.
Why forwarded mail can fail checks
Receiving servers check incoming mail with SPF, DKIM and DMARC to decide whether a message really comes from the domain it claims. SPF, DKIM and DMARC explained covers each in detail. Forwarding can interfere with these checks:
- SPF checks whether the server sending the message is allowed to send for the sender's domain. When a message is forwarded, it arrives from the forwarding server, which the original sender never listed. SPF can therefore fail.
- DKIM adds a signature to the message. It usually survives forwarding as long as the message is not changed on the way, but some forwarders add footers or edit subject lines, which breaks the signature.
- DMARC passes if either SPF or DKIM passes for the sender's domain. If SPF fails and the DKIM signature was broken, DMARC fails, and the destination may move the message to spam or reject it.
Two techniques reduce these problems:
- SRS (Sender Rewriting Scheme) changes the hidden return address on a forwarded message to one at the forwarding service, so SPF is checked against a server that is allowed to send.
- ARC (Authenticated Received Chain), described in RFC 8617, lets the forwarding service record the check results it saw when the message first arrived. Destinations that trust that service can use those results.
You cannot control whether senders or destinations support these, but a forwarding service that uses them gives better delivery.
Signs that forwarding is losing mail
- Messages from some senders never arrive, while others do.
- Forwarded mail lands in the destination's spam folder.
- Senders get bounce messages that mention SPF or DMARC.
If this happens often, a mailbox at your domain is more reliable than forwarding to another provider. Email not arriving helps you read bounce messages.
Replying from the forwarded address
Forwarding only handles incoming mail. When you reply from your personal inbox, the reply normally comes from your personal address, not from hello@example.com.
Some email apps and services let you add a "send mail as" address. This only works well if the service sends through an outgoing (SMTP) server that is authorized for your domain, and that server is included in your domain's SPF record and signs with DKIM. Without that, replies that claim to come from your domain can fail DMARC and be rejected.
If you regularly need to send from your domain address, use a mailbox at your domain instead, set up in your email app as described in Set up email on your devices.
Email forwarding to an existing inbox is included with every domain registered with DomainPilot. For mailboxes at your own domain, see DomainPilot business email.