domainwidedelegation.comStart free

Use cases → Admin and governance

Update email signatures for every user in the domain

Automate consistent email signature changes across all users by applying updates centrally with a delegated service account.

Who it is forIT administrators responsible for enforcing brand consistency or legal disclaimers in email signatures.
APIsGmail API, Admin SDK
Typical scopesgmail.settings.basic, admin.directory.user.readonly

The problem

Manual signature updates rely on user compliance, resulting in inconsistent branding and risk of outdated legal text. Bulk updates by hand are not feasible at scale, especially during rapid company changes.

How it works

  1. Fetch the list of active users via the Admin SDK.
  2. For each user, impersonate them using domain-wide delegation.
  3. Apply the new signature using the Gmail API’s 'SendAs' settings endpoint.
  4. Log results and retry failures after a back-off period.

What changes

All users have their signatures updated centrally, ensuring consistency and reducing manual compliance checking.

The trap in this one. The Gmail API’s signature update endpoint is rate-limited per user, but also per admin, and does not surface all errors synchronously. If you update too many users too quickly, the API may silently ignore requests or apply them out of order. Always stagger updates and verify signatures post-change, as some updates can be dropped without an error response.

Watch it explained

“How to integrate eSign with Google Workspace | Integrating Zoho Sign with Google Workspace” — Zoho Sign on YouTube. Third-party video, included because it covers this ground well. We are not affiliated with the channel.

Questions people ask

Can I update signatures for suspended or recently deleted users?

No. The Gmail API will return an error for suspended or deleted accounts, but these errors are not always explicit. Filter your user list before attempting updates.

Will users see the change immediately?

Not always. There is often a propagation delay of several minutes, and cached signatures may persist in some clients until restart.

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

Related use cases

Automate joiners, movers and leavers

Create accounts, set group membership, provision Drive and hand over mailboxes without a manual checklist.

Continuously verify your delegation still works

A scheduled probe that proves every API still answers under every tenant, before a customer finds out otherwise.

Reduce an over-broad delegation grant safely

Find out which scopes your automation genuinely uses, then cut the grant down to them.