Your experience will vary and each situation is unique. This is a loose guide of steps that help to at least consider, if you don’t do it. This is for you technical support team members that guide your clients and companies to make a logical change. You are welcome to share this list or you can also fill out this form if you need help.

Phase 1: Discovery & Scoping

  • Gather details with a structured questionnaire:

    • Number of users and mailboxes
    • Shared/team mailboxes (sales@, support@)
    • Aliases in use
    • Domains tied to Microsoft 365
    • Licensing requirements (email only, Office apps, storage)
    • User habits (desktop Outlook classic/new, Outlook web, mobile, Gmail)
    • Mailbox size, local PST/OST storage
    • Compliance or retention requirements
  • Confirm primary contact and availability for live support during migration.
  • Deliverable: migration plan and quote with assumptions clearly documented.

Phase 2: Pre-Migration Setup

  • In Google Admin:

    • Create user accounts and assign licenses.
    • Enable and enforce 2FA.
    • Generate DKIM key.
  • In DNS (Cloudflare):

    • Set MX records to Google.
    • Add SPF, DKIM, and DMARC records.
  • On the client side:

    • Export PSTs from Outlook (after cleaning up Sent/Deleted folders).
    • Confirm OneDrive/SharePoint usage.
    • Notify all users of the cutover timeline.
  • Deliverable: Google accounts ready, DNS prepared, PST backups completed.

Phase 3: Cutover Execution

  • Update MX records to Google.
  • In Outlook:

    • Create new profiles.
    • Add Google Workspace accounts (prefer Google OAuth).
    • Attach PST files for history.
  • On user devices:

    • Reconfigure mobile apps for Google accounts.
    • Remove Microsoft 365 mailboxes.
  • Test mail flow:

    • Gmail web send/receive.
    • Outlook desktop send/receive.
    • Alias “Send as” addresses.
    • Mobile sync.
  • Deliverable: Google Workspace fully live for all users.

Phase 4: Post-Migration Validation

  • Send test messages to external clients, especially strict BPOs and corporate recipients.
  • Review Gmail headers to confirm SPF, DKIM, and DMARC all pass.
  • Verify shared/team mailboxes and aliases function correctly.
  • Confirm forwarding rules used for transition are removed.
  • Train users on:

    • Using 2FA
    • Default “Send as” behavior
    • Accessing old PST archives
  • Deliverable: client confirmation that all mail services work.

Phase 5: Cleanup and Billing

  • Remove unneeded Microsoft 365 mailboxes and licenses.
  • Retain or downgrade Office app licenses if required.
  • Archive PST backups securely.
  • Document new configuration for the client.
  • Invoice for:

    • Discovery and scoping
    • Pre-migration setup