Use different signatures for internal and external email

Many organisations want a light signature on mail between colleagues and the full signature, with logo and legal wording, on mail to the outside world. A rule's Recipient type, under Who it goes to, does this. This article explains how to set it up and how Footer365 decides whether an email is internal or external.

How Footer365 decides

A recipient is internal when their address is in one of your organisation's own email domains, the domains Footer365 has synced from Microsoft 365, and external otherwise. Everyone on To and Cc counts.

Recipient type offers five choices:

A mixed email never matches Every recipient internal, on purpose. The internal signature is usually the one without the confidentiality notice, so sending it outside by mistake is the costly error. A colleague seeing the external signature does no harm.

To aim a rule at particular customers or partners rather than at everyone outside, add their addresses or domains under Only when recipients include. See Rules for particular recipients.

Bcc recipients get the same signature

Microsoft 365 sends a Bcc recipient a separate copy of the email. Footer365 decides internal or external for that copy from the email's To and Cc recipients as well as its Bcc recipients, so the Bcc copy gets the same signature as everyone on To and Cc.

This matters most when you Bcc your own mailbox, or a colleague, to keep a record of what you sent a customer. The customer is outside your organisation, so the email is external, and the Bcc copy in your own mailbox has the full signature and any campaign banner the customer's copy had. What you keep is what the customer received.

The one exception is a Bcc recipient outside your organisation on an email whose To and Cc recipients are all colleagues. The colleagues get the internal signature, and the outside Bcc recipient gets the external one, for the same reason mixed mail is treated as external: the internal signature never goes outside. If you would rather every copy got the external signature in this case too, see Bcc signature matching.

If your account has the audit log, an email with a Bcc recipient still has one entry there. Its details show a row for the To and Cc copy and a row for the Bcc copy, each with the rule, template and campaign banner that copy was signed with and how many recipients it went to, so you can see which signature each set of recipients received.

Set up internal and external signatures

You need two rules, with the internal one above the other.

1. Open Signature rules.
2. Select New rule and create the internal rule. Where your organisation has the rule wizard, select the arrow beside New rule and then Start blank in the editor, because Every recipient internal is set in the editor:
   • Rule name: for example "Internal - short".
   • Signature template: your short template.
   • Who sends it: All users, or a narrower audience.
   • Recipient type: Every recipient internal.
   • Email type: All emails.
3. Select Save rule.
4. Make sure you also have a rule below it with Recipient type set to All recipients and your full template. This is your fallback. See Add a fallback rule.
5. Drag the internal rule above the fallback rule if it is not already there.

Mail to colleagues now matches the internal rule. Everything else, including mixed mail, skips it and falls through to the full signature.

Why not use Any external recipient?

You can create a rule with Any external recipient, but on its own it leaves internal mail with no signature. If you use it, add a rule below it that covers All recipients, or an Every recipient internal rule, so colleagues are covered too.

The pattern above, an internal rule plus a fallback for everyone, is the simplest way to be sure nothing slips through.

In Outlook with the add-in

The Outlook add-in uses the same rules and decides internal or external in the same way.

• The signature is worked out again when you change the recipients, so adding an outside address to a draft switches it to the external signature.
• If the add-in cannot read the full list of recipients, it treats the email as external.
• A meeting invitation gets the external signature where one applies, because the add-in inserts it once and does not change it as attendees are added.

Check the result

Select Test a rule, pick a person and type the recipients' addresses under Recipients. Add a colleague and an outside address together to see what a mixed email would get. See Test a rule.

Good to know

• Only your own synced domains count as internal. Mail to a partner organisation or a separate Microsoft 365 organisation in your group counts as external.
• An email with no recipients Footer365 can read is treated as external.
• The recipient type works alongside the other parts of a rule. A rule for Replies only and Every recipient internal matches only internal replies.
• For legal wording that only external mail should carry, you do not need a second template: add it on the Disclaimers page and set its Recipient type to Any external recipient. It is then added under whichever signature the rules choose. See Disclaimers.

Related

• How signature rules work
• Rules for particular recipients
• A different signature for replies
• Bcc signature matching
• Which messages are signed