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Use cases → Email operations

Update every user's Gmail signature centrally

Push a new standard signature to all users' Gmail accounts using domain-wide delegation and the Gmail API.

Who it is forIT and comms teams rolling out company branding or compliance changes.
APIsGmail API
Typical scopesgmail.settings.basic

The problem

Manual signature changes are ignored or delayed by users, leading to inconsistent branding and missing legal disclaimers. Bulk updates by admin are not natively supported in the UI.

How it works

  1. Create a delegated service account with the gmail.settings.basic scope.
  2. Fetch the list of target users from the directory.
  3. For each user, impersonate and update their signature via the Gmail API.
  4. Log which accounts were updated and which failed for later follow-up.

What changes

All users receive the new signature without relying on individual action, and compliance is enforced with a single operation.

The trap in this one. The Gmail API's signature update endpoint is not eventually consistent: if you update signatures for many users in rapid succession, some API calls silently succeed but do not apply the change. This is most common when updating hundreds of accounts in parallel. Always re-read the signature after updating and retry failed updates, or some users will retain the old signature with no error or warning.

Questions people ask

Can you set different signatures for different organisational units?

Yes, but you must implement the logic yourself. The API only sets per-user signatures, so you need to map users to their intended signature template.

Does this affect mobile clients?

No. Mobile Gmail clients use their own signature settings, which are not managed by the API. Users will need to update those separately.

Want this built?

This is a pattern we run in production. We will set up the delegation and build this on top of it — $500 per hour, most of it working the same day.

Talk to us Or read the setup guide

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