Microsoft has officially set the end-of-life date for both Exchange Server 2016 and Exchange Server 2019: October 14, 2025. That might sound like a long way off, but in IT terms, it’s right around the corner, especially if your organization still relies on Exchange for SMTP relay, hybrid identity, or legacy app integration.
Here’s what’s changing and how to prepare.
What’s Replacing Exchange 2016 and 2019?
Instead of releasing a new standalone version of Exchange, Microsoft is moving to a subscription-based model called Exchange Server Subscription Edition (SE). Think of it as an evolution of Exchange 2019, it uses the same codebase, but comes with a different licensing model and a “stay current” support requirement.
In other words: no more perpetual licenses. You’ll need to stay on a supported cumulative update and be properly licensed (typically through Microsoft 365 or volume licensing) to keep things running.
What Does This Mean for You?
If you're still running Exchange 2016, you’ll need to migrate to a new server running Exchange SE. Unfortunately, there's no in-place upgrade path, so this is a side-by-side deployment.
If you're already on Exchange 2019, the transition is easier. You won’t need to reinstall anything; you’ll just need to apply a new Exchange SE product key and make sure you're running the latest cumulative update.
Why Keep Exchange On-Prem?
We still see a lot of customers who’ve fully adopted Exchange Online but keep one on-premises Exchange server around for things like:
- SMTP relay for printers, scanners, or older line-of-business apps
- Hybrid identity management
- Specific compliance or regulatory needs
For those customers, Microsoft offers a free Hybrid Edition license, as long as you're using the server for hybrid management only and not hosting mailboxes.
What Are Your Options?
Here’s a quick look at the upgrade paths:
If you’re on Exchange 2016:
- Deploy a new Exchange SE server (based on Exchange 2019)
- Migrate SMTP connectors, certificates, and settings
- Move off the old server and decommission it before the EOL date
If you’re on Exchange 2019:
- Apply the Exchange SE product key
- Stay current with updates to maintain support
Don't Forget About SMTP Relay
One of the biggest drivers for keeping Exchange on-prem is SMTP relay. This is especially true if your organization has legacy printers or systems that can’t authenticate directly with Exchange Online. While Microsoft does offer relay options through Exchange Online, they often require modern authentication (OAuth), which isn’t always compatible with older hardware.
Exchange SE is still the best fit for environments that need to bridge that gap.
Need Help?
If you’re not sure which direction to go, or you want to put a plan together to upgrade and future-proof your Exchange environment, Gotham can help.
We’ve guided dozens of customers through Exchange upgrades, hybrid deployments, and SMTP relay migrations. Whether you’re looking to stick with Exchange SE or move toward native Microsoft 365 options, we’ll help you find the right path.
Reach out to us anytime to schedule a consultation.