The Ultimate Exchange Online Migration Checklist

Support windows are closing on Exchange 2016 and 2019. Get the step-by-step checklist our team uses to move companies to Exchange Online with zero data loss, and no surprise downtime.

Trusted by organizations worldwide

Team Venti did a fantastic job helping us upgrade our Exchange server and decommission the old one. The entire process went very smoothly. I highly recommend.

Tom Murawski IT Manager - SDI Technologies Inc.

Working with Team Venti from pre-sales to post-deployment has been such an amazing and seamless experience. Migrating from our on-prem environment to the cloud was no easy task, however, the engineers that were assigned to this project were super knowledgeable and went above and beyond for us in several situations to ensure business impact was kept to a minimum. Would love to work with Team Venti again in future projects and highly recommend them to anyone who is looking for an SME to partner with for critical technological transformations to your business.

Reed Mattadeen IT Manager – Titanium Transportation Group Inc.

Migrating to Exchange Online benefits your business by:

Cutting IT costs by reducing the number of Exchange Server licenses

Protecting your email from ever-evolving threats

Giving users anywhere, anytime access to email and calendars, boosting collaboration

Automatic updates for your Exchange Online environment to ensure you always have the latest features

This checklist, created by Team Venti’s migration experts, offers a step-by-step approach to ensure a seamless transition for your business.

Team Venti’s Microsoft Exchange expertise

17+

Years of Experience in Microsoft Technologies

100+

Exchange Migrations

Microsoft Cloud Partner of the Year

100%

Microsoft Exchange Experts

What's inside the Exchange Online migration checklist?

Pre-migration preparation

Define migration goals, design the new Exchange architecture (for hybrid environments) or environment you want, develop a communication plan for your users, and prepare the new environment you are moving into.

Migration execution

Execute the migration according to your goals and detailed plan made on the pre-migration stage. Schedule downtime for cutover to minimize disruption and test everything in the new environment.

Post-migration tasks

Provide comprehensive user training, decommission the previous Exchange server(s), continuously monitor your new Exchange Online environment performance, and identify areas of optimization.

Every day you stay on Exchange Server 2016/2019 is a day without security patches

End of Extended Support: October 14, 2026
End of Period 2 Extended Security Updates (ESU): October 31, 2026

FAQs

How long does an Exchange Online migration actually take?

Most migrations run 4–8 weeks from kickoff to cutover, depending on mailbox count and how complex your current environment is. You’ll get a firm timeline before we start.

Will my team lose access to email during the move?

No planned outage. We migrate mailboxes in the background and schedule the final cutover during a low-impact window, so users keep sending and receiving mail throughout the project. The only thing that changes is a brief sign-in prompt when their mailbox switches over.

What happens to our existing email and data during the migration?

Every mailbox, calendar, and contact is copied, not moved, so your original data stays intact on the old server until you’ve confirmed everything landed correctly in the new environment. Nothing is deleted until you sign off.

We are here to help, no matter your destination

Based in the beautiful Austin, Texas