Forward a copy of incoming mail

Use this guide when services send things other than receipts to your receipt address, such as sign-in codes or account notices, and you want to see them. With FORWARD_COPY_TO set, the Worker forwards a copy of every message it receives, from any sender, to one address of yours.

Prerequisites

Email set up and working; see Set up email.
An inbox that is not the receipt address itself, for example your personal mailbox.

Steps

Verify the destination address in Cloudflare
Cloudflare only forwards to verified destination addresses. In the Cloudflare dashboard, go to Compute > Email Service > Email Routing > Destination Addresses, enter the address and submit it. Open the email Cloudflare sends to that address and select Verify email address.
Set the address in the app
Open Settings > Email and fill in Forward a copy to. Tick “This address is a verified destination in Email Routing”, which shows once you change the address, and press Save.
The app cannot check that the address is verified. If it is not, the copies are lost and each failure is logged as forward_copy_failed.
To set it at deploy time instead, use the FORWARD_COPY_TO variable. A value saved in the app wins over the variable.
Send a test
Send a message to the receipt address from any address, allowed or not.

Check it worked

The message arrives in the destination inbox, forwarded by Cloudflare. If it came from an allowed sender, it is also read as a receipt as usual.

What to expect

Only one address is supported, because Cloudflare forwards each message once.
Forwarding runs alongside receipt reading. A failed forward never stops a receipt being read, and a failed read still forwards.
The copy itself is not stored, and it is not read by AI unless its sender is allowed in Settings > Email > Email senders.
A destination equal to the address the message was sent to, the receipt address or the invoice address is skipped to avoid a loop, and logged as forward_copy_loop.
FORWARD_COPY_TO must differ from the invoice address if you use one.

To turn forwarding off, clear the field and save, or press Reset next to it if the value came from the app.

Email and sender trust
Configuration for FORWARD_COPY_TO.