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Use cases → Admin and governance

Update email signatures across the company

Push a new standardised email signature to every user’s Gmail account using a delegated service account, ensuring compliance and branding consistency.

Who it is forIT admins and compliance teams responsible for branding and legal disclaimers.
APIsGmail API
Typical scopesgmail.settings.basic

The problem

Manual signature updates rely on users and result in inconsistent branding or missing legal text. Compliance and marketing teams have no way to verify or enforce company-wide changes.

How it works

  1. Prepare the new signature in HTML, including images hosted on a public, reliable CDN.
  2. Enumerate all active users via the directory API or a maintained list.
  3. Use domain-wide delegation to impersonate each user and call Users.settings.sendAs.patch for their primary email.
  4. Log which accounts are updated and flag failures for follow-up.
  5. Schedule periodic reapplication to catch new joiners or signature drift.

What changes

All users receive the correct signature automatically, with a record of which accounts have been updated.

The trap in this one. Gmail API’s sendAs.patch silently ignores changes if the user has never sent mail from the web interface, resulting in no signature being applied and no error returned. This typically affects new accounts or service accounts created by automation. Always verify post-update by reading back the signature, and expect some accounts to require first-run initialisation by the user.

Questions people ask

Can images be embedded directly in the signature?

No. The Gmail API only supports linked images, not embedded or base64 data. Use HTTPS links to reliably hosted images.

How often should the update run?

At least daily for large or high-turnover organisations, or whenever there is a signature change, to ensure new users are covered.

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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