Microsoft is ending support for Exchange Server 2016 and 2019 on October 14, 2025. No more security updates. No more bug fixes. No more support. 

If you’re still running Exchange on-prem, especially in legal or regulated industries, this should be on your radar now. 

  

Microsoft’s Exchange End-of-Life Timeline 

Microsoft is set to release Exchange Server Subscription Edition (SE) in July 2025. Organizations will then have just 90 days to migrate before support ends for Exchange 2016 and 2019. 

There’s no “quick fix” path here. Whether you’re moving to SE or Exchange Online, these migrations require serious planning and execution. Most environments will need: 

  • New Exchange servers 
  • Mailbox and public folder migration 
  • Licensing upgrades 
  • Cleanup of hybrid or coexistence issues 

 

Your Migration Options 

Here’s what the options look like today: 

If you’re on Exchange 2019 CU15: You can do an in-place upgrade to Exchange SE 

If you’re on Exchange 2016: You’ll need to: 

  • Migrate to Exchange 2019 CU15, then upgrade to SE 
  • Or go directly to SE (typically more complex) 

Either path involves multiple steps, infrastructure work, and license reviews. 

 

Why It’s Urgent to Plan Now 

A lot of legal and enterprise IT teams have put off full Exchange Online migrations due to compliance, security, or integration concerns. With SE launching in July and support ending in October, you’ve got about 90 days to complete a migration if you wait. That’s a tight timeline, especially if you’re running multiple Exchange servers or supporting remote and hybrid work. 

 

How Canalini Can Help 

At Canalini, we specialize in helping firms with complex Microsoft infrastructure, especially in legal and regulated environments. Exchange EOL projects are in our wheelhouse, and we know how to manage them without disrupting day-to-day operations. 

  • Discovery and assessment of your current Exchange setup 
  • Migration from Exchange 2016 to 2019 (if needed) 
  • Upgrade to Exchange SE or transition to Exchange Online 
  • Licensing review and support 
  • Cleanup and post-migration validation 

The biggest lift is usually moving from Exchange 2016 to 2019. That work should happen this summer if you want a clear path to Exchange SE before the deadline. 

And remember: Exchange SE hasn’t been released yet, so waiting until July to start planning puts you in a real time crunch. 

 

Next Steps 

If you’re still running Exchange on-prem and aren’t sure what your next move should be, we should talk. 

We’re helping IT teams get ahead of the Exchange end-of-support deadline—before timelines get tight and internal teams get stretched. 

  • Already planning to move? We can help you: 
  • Audit your current Exchange deployment 
  • Choose the right migration path (Online or SE) 
  • Build a clear, staged plan that fits your timeline and internal resources 
  • Ensure licensing isn’t a blocker later on 

  

Book a 30-minute call with our team. 

Or reach out directly: info@canalini.com