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Use cases → Admin and governance

Synchronise contact lists across multiple accounts

Keep user or shared contacts aligned with an external source using a delegated service account to drive updates at scale.

Who it is forIT or automation teams managing address books for sales, support or shared mailboxes.
APIsAdmin SDK
Typical scopesadmin.directory.user, admin.directory.user.readonly

The problem

Contact information becomes inconsistent and outdated when managed locally, leading to misdirected mail and wasted time. Manual updates do not scale and are error-prone.

How it works

  1. Extract the source-of-truth contact data from your database or CRM.
  2. Use domain-wide delegation to impersonate each target user or mailbox.
  3. Compare and upsert contacts via the People API for each account.
  4. Remove stale or unauthorised entries to maintain integrity.
  5. Log all synchronisation actions for traceability.

What changes

Contacts remain consistent across accounts, reducing confusion and keeping communication flowing with the right information.

The trap in this one. The People API batches writes but silently skips updates if a contact is unchanged according to its internal fingerprint, even if external systems see a difference (such as whitespace, label order or non-visible fields). This can leave contacts partially unsynchronised with no reported error. Always canonicalise and normalise contact data before writing, and compare the actual API-returned contact object after update to ensure true alignment.

Watch it explained

“Google Workspace Bulk Administration Tutorial 2026 | SheetOps Getting Started” — SyncWithTech on YouTube. Third-party video, included because it covers this ground well. We are not affiliated with the channel.

Questions people ask

Can this sync shared mailbox contacts as well as user accounts?

Yes, provided the service account is delegated to impersonate the shared mailbox and the mailbox has been created as a user resource.

How often should synchronisation run?

It depends on the business process, but at least daily is typical for organisations with fast-moving contact data.

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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