Email migrations go wrong quietly: lost history, broken mail flow, a Monday morning of angry tickets. Billow's email migration services move you to Microsoft 365 — from Exchange, Google Workspace or another tenant — with zero downtime, no data loss, and users who barely notice.
Email migration is the process of moving mailboxes — messages, calendars and contacts — from one email system to another, most commonly from on-premises Exchange or Google Workspace to Microsoft 365. Done well, it moves all your historical data intact, keeps mail flowing throughout, and switches users over with minimal disruption.
Email feels simple until you move it. Years of history, shared mailboxes, distribution lists, calendar permissions, mail-flow rules and DNS all have to come across correctly — and the cutover has to be timed so mail never stops. Get any of it wrong and the symptoms are painful and public: missing history, bounced messages, broken calendars, and a helpdesk buried in tickets. The difference between a smooth migration and a painful one is almost entirely in the planning and validation.
Billow handles the whole email migration for you — assessing the source, choosing the right method (cutover, staged, hybrid or tenant-to-tenant), pre-staging the data, and cutting over with mail flow and DNS timed to avoid disruption. Whether you're migrating to Microsoft 365 from Exchange, running an Office 365 migration from an older tenant, moving off Google Workspace, or consolidating tenants after a merger, we get your email across with zero downtime and no data loss.
Our email migration services cover every common source and scenario — planned, executed and verified end to end.
Migrate from on-premises Exchange to Exchange Online — cutover, staged or hybrid, matched to your size and timeline.
Move from Gmail and Google Workspace to Microsoft 365 — mail, calendars and contacts across cleanly, users mapped and cut over.
Consolidate or split Microsoft 365 tenants after a merger, acquisition or divestiture — coexistence and cutover managed.
Migrate from IMAP servers, POP, PST archives or other legacy platforms into Microsoft 365 with data intact.
Discovery, method selection, mail-flow and coexistence design so both systems work side by side until cutover.
DNS and mail-flow cutover timed to avoid disruption, with post-migration verification before the old system is retired.
That's the whole point. A migration done well is invisible — people arrive Monday, their mail and history are there, and everything just works. A migration done badly is a week your organization won't forget. The gap is planning and experience.
Mail keeps flowing throughout. Cutover is timed and coexistence managed so people are never left without email.
Every mailbox, calendar, contact and years of history migrated and verified — nothing lost, nothing orphaned.
Cutover, staged, hybrid or tenant-to-tenant — we pick the approach that fits your size, source and timeline, not a one-size template.
Clear comms, profile reconfiguration and support around cutover mean a smooth switch — not a flood of helpdesk tickets.
Whatever you're on today, we've moved it to the cloud — with the right tooling and method for each source.
Exchange migration
Gmail migration
Tenant-to-tenant
01
We inventory mailboxes, data volumes and dependencies, pick the right migration method, and build the cutover plan.
We set up the target, establish coexistence, and pre-migrate the bulk of mailbox data ahead of cutover to shrink the switch.
We switch mail flow and DNS at the right moment, reconfigure clients, and move the final delta — with mail never stopping.
We confirm every mailbox migrated, support users through the change, and decommission the old system once all is clean.
Email migration is usually the first step into Microsoft 365. These connect to it most closely.
The full practice this sits within — Microsoft 365, device management, virtual desktops and workplace transformation.
Once your email is across, we configure, secure and manage the full Microsoft 365 environment around it.
Moving more than email? Our cloud migration practice moves apps, servers and data to the cloud too.
Whether it's Azure Virtual Desktop, Windows 365 Cloud PCs, or a hybrid of both, tell us about your users and we'll design virtual desktops that are secure, fast and cost-right.
