Outlook to Gmail
Migration

Two different migrations, same destination

Individual mailbox migration: One Outlook account, with its email, contacts, and calendar moving into Gmail — typically handled via IMAP or Gmail's built-in mail import tools. This is something a single user can reasonably do without admin-level access.

Company-wide migration: An entire organisation moving from Microsoft 365 to Google Workspace, with Gmail replacing Outlook for every employee. This requires Google Workspace admin access, Microsoft 365 admin access, and a structured, batched migration — not something done mailbox-by-mailbox by hand at any meaningful scale.

What actually moves

For both approaches, the same three things move:

• Email — every message, with Outlook's folder structure converting to Gmail labels
• Contacts — Outlook Contacts move to Google Contacts
• Calendar — Outlook Calendar events, including recurring meetings, move to Google Calendar

What doesn't move automatically: Outlook rules and any Exchange-specific transport rules, which need to be manually recreated as Gmail filters, since the two platforms handle mail rules differently under the hood.

Outlook folders vs. Gmail labels

This is the reverse of the challenge covered in our Gmail to Outlook migration guide. Outlook folders hold a message in exactly one place; Gmail labels let a single message carry multiple labels simultaneously. When migrating from Outlook, each folder typically converts to a corresponding Gmail label — a cleaner, more predictable conversion than the reverse direction, since going from "one place" to "one label" is more direct than the reverse.

Step-by-step: migrating a single Outlook mailbox to Gmail

1. Enable IMAP access in your Outlook/Microsoft 365 mail settings, if it isn't already enabled.
2. Add the account to Gmail via Gmail's "Import mail and contacts" feature, or configure Gmail to fetch mail via IMAP.
3. Let the import complete — for mailboxes with years of accumulated mail, this can take a while; the process runs in the background but shouldn't be interrupted.
4. Recreate any Outlook rules manually as Gmail filters, since these don't transfer automatically.
5. Verify calendar and contacts imported correctly, particularly recurring calendar events.

Step-by-step: migrating an entire company from Microsoft 365 to Google Workspace

This runs at the admin level, not per-mailbox:

1. Discovery — inventory every mailbox, shared mailbox, distribution list, and calendar resource in Microsoft 365.
2. Google Workspace setup — provisioning users and licenses before anything migrates.
3. Domain and DNS preparation — verifying your domain in Google Workspace and preparing MX record changes for cutover.
4. Batched migration — mailboxes migrated in planned groups rather than all at once.
5. Delta sync — a final pass catching mail received between initial migration and cutover.
6. MX cutover and validation — mail routing switches to Google Workspace, with item counts verified before the Microsoft 365 environment is decommissioned.

This is the process covered in more depth in our Microsoft 365 to Google Workspace migration guide.

Which approach is right for you?

A single mailbox is reasonable to move yourself with an afternoon set aside for verification. A full company migration — anything beyond a handful of users, or any organisation with shared mailboxes, distribution groups, or Teams data to account for — is worth treating as a structured project rather than a DIY task.