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Use cases → Email operations

Send onboarding welcome emails to new users at scale

Blast a tailored onboarding email to every new user as their account is created, using a delegated service account to send from HR or IT.

Who it is forIT or HR teams responsible for onboarding large cohorts of new users.
APIsGmail API, Admin SDK
Typical scopesgmail.send, admin.directory.user.readonly

The problem

Manual welcome emails are error-prone and easily missed, especially during bulk hiring or reorgs. Relying on end users to check onboarding docs results in inconsistent first-day experiences.

How it works

  1. Watch for new accounts by polling the Admin SDK for recently created users.
  2. For each new user, use the service account with domain-wide delegation to impersonate a sender (e.g. hr@ or it@) and send a templated welcome email via the Gmail API.
  3. Log sent emails and any errors for audit and follow-up.
  4. Throttle requests to avoid Gmail API send limits and avoid being flagged for spam.

What changes

Every new user receives a consistent, timely onboarding email from a trusted internal sender, with delivery tracked centrally.

The trap in this one. The Gmail API's send method will silently drop messages if the delegated sender's mailbox has not been accessed in the web UI at least once, even though the API call returns 200. This is not documented in the main API guides, so you can blast emails to hundreds of new users and only discover days later that none arrived. Always script a one-time login for any sender account before using it for automated sends.

Questions people ask

Can I send from each user's own account?

Technically yes, but users will see the sent message in their own Sent folder, which may be confusing. It's more common to send from a central HR or IT address.

How do I avoid sending duplicates?

Track the last processed user creation timestamp or user ID, and always log sent emails with a unique reference. Idempotency is critical if your process restarts.

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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Send onboarding welcome emails as a delegated service

Automate welcome emails for new users by sending from a delegated account, ensuring consistency and timely delivery for every new joiner.