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Exchange Team Blog
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Support for Exchange Server 2016 and Exchange Server 2019 ends today

The_Exchange_Team's avatar
The_Exchange_Team
Platinum Contributor
Oct 14, 2025

Today, October 14, 2025, Exchange Server 2016 and Exchange Server 2019 reach end of support. It’s critical to upgrade now to remain supported and secure.

Microsoft will no longer provide technical support, meaning that Exchange 2016 and Exchange 2019 users will no longer receive:

  • Bug fixes for issues that may impact the stability and usability of the server.
  • Security fixes for vulnerabilities that may make the server vulnerable to security breaches.
  • Time zone updates.

Customer installations of Exchange 2016 and Exchange 2019 will continue to run after October 14, 2025. However, continuing to use these offerings after the end-of-support date invites potential security risks, so we strongly recommend taking action now.

Our recommendation is for customers to migrate to Exchange Online or to upgrade to Exchange Server Subscription Edition (SE).

Migrate to Exchange Online or Microsoft 365

We strongly believe that customers get the best value and user experience by migrating fully to Exchange Online or Microsoft 365. Migrating to the cloud is the best and simplest option to help you retire your Exchange Server deployment. When you migrate to the Microsoft cloud, you make a straightforward hop away from an on-premises deployment and benefit from new features and technologies, including advanced generative AI technologies that are available in the cloud but not on-premises.

If you’re migrating to the cloud, you might be eligible to use our Microsoft FastTrack service. FastTrack shares best practices and provides tools and resources to make your migration as seamless as possible. Best of all, you’ll have a support engineer helping you, from planning and designing to migrating your last mailbox. For more information about FastTrack, see Microsoft FastTrack.

Upgrade to Exchange Server SE

In July 2025, we announced the general availability of Exchange Server SE with details on how to upgrade if you intend to continue to run Exchange Server on-premises.

  • If you are running Exchange 2019, we recommend that you upgrade in-place to Exchange Server SE.
  • If you are running Exchange 2016, we recommend that you perform a legacy (a.k.a. side-by-side) upgrade to Exchange Server SE.

If you still have Exchange Server 2013 or earlier in your organization, you must first remove it before you can install Exchange Server 2019 CU15 or upgrade to Exchange Server SE.

Exchange Server Technology Adoption Program

If your organization intends to continue running Exchange Server and you want to test and evaluate pre-release builds of Exchange Server SE releases, you can apply to join the Exchange Server Technology Adoption Program (TAP).

Joining the Exchange Server TAP has several advantages, such as the ability to provide input and feedback on future updates, develop a close relationship with the Exchange Server engineering team, receive pre-release information about Exchange Server, and more. TAP members also get support from Microsoft at no additional charge for issues related to the TAP.

All nominations are reviewed and screened prior to acceptance. No customers are allowed access to any pre-release downloads or information until all legal paperwork is properly executed. Nomination does not mean acceptance, as not all nominees will be chosen for the TAP. If you are preliminarily accepted, we will contact you to get the required paperwork started.

Exchange Server Team

Updated Oct 14, 2025
Version 2.0
announcements
exchange 2016
exchange 2019
on premises
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15 Comments

  • KenS2's avatar
    KenS2
    Copper Contributor
    Oct 21, 2025

    I am having trouble getting a proper quote for Exchange Server Subscription Edition (Standard) server and CALs for my on-prem Exchange Server. Can someone help me with the correct part numbers for SE edition? I am getting the standard 2019 server quotes not for the Subscription edition. 

  • brianlangford's avatar
    brianlangford
    Copper Contributor
    Oct 20, 2025

    Is there any guides yet for what people who are on 2025 DC's with 2025 FFL are supposed to do in light of the current bug?

    • Nino_Bilic's avatar
      Nino_Bilic
      Icon for Microsoft rankMicrosoft
      Oct 20, 2025

      My recommendation would be to wait; last I heard, the fix should be in November Windows updates (this may change).

      • brianlangford's avatar
        brianlangford
        Copper Contributor
        Oct 20, 2025

        Ok, I will do that thanks. Do you have a link or something that I can monitor the status of this, and if it gets resolved in November?

        I want to minimise my time on an exposed Exchange 2016 at this point. 

  • ITSystemsMSP's avatar
    ITSystemsMSP
    Copper Contributor
    Oct 19, 2025

    Is there going to be a proper communication at some point to SPLA customers to notify them if Exchange SE is actually permitted under SPLA because the SPUR governs usage and it still only refers to Exchange Server 2019 - can someone please nudge those responsible to actually update the SPUR etc - it's all well and good having the downloads for SE available but the license agreement for SPLA is clear that it must be covered by the SPUR - and it isn't...

      • poait's avatar
        poait
        Copper Contributor
        Oct 20, 2025

        Well, that clears THAT up, LOL.  I guess it's safe to say until a reseller can confidently tell me, "Here's your license for Exchange SE," I'll stick with my licensed and fully functional 2019 deployment, on the assumption that such licenses will be available (and understandable) sometime fairly soon.

        Will MS be blocking old versions of non-Exchange servers from sending email to their hosted servers?  Or just old Exchange servers?  It seems to me the world is full of existing systems to block compromised servers, ie blacklists.  If a server is not compromised/blacklisted, there isn't any excuse for blocking email from it.

  • slansing's avatar
    slansing
    Copper Contributor
    Oct 17, 2025

    Moving online costs significantly more than running my own email server.  Moving online exposes me to the unpredictable and fairly regular down times on the Internet in general.  Moving online when I have strict backup requirements for my business adds a very large expense, compared to running my own backups in-house.  Finally, moving online is going to change the user experience enough that it is no longer a deterrent to move to a non-MS email server that I can run in-house for the long run without any hassles.  If I'm going to change things up I'm going to take the opportunity to get off the treadmill.  The lack of SE licensing at this point is concerning.  I am compelled to do the research and look at alternatives because it feels like the walls are closing in.  It's email. It's not rocket science.  I just need to send and receive email and calendar items.  I don't need "AI" or "new features and technologies".  I just need an email server.  If MS squeezes any harder on this I'm pulling the cord.  Give us the license, stop gouging us, stop trying to force OUR businesses to do things for YOUR benefit.  Software and computers are tools we use to serve us, not the other way around.  That's why we pay for them.  Not so that they can dictate how we do everything and bleed us dry.  Frustrated.  Can't get a straight answer on licensing from mainstream vendors, because they have no information either.

    • MrOCanada2280's avatar
      MrOCanada2280
      Copper Contributor
      Oct 20, 2025

      Licensing comment answered by Microsoft.. the rest, I know how you are feeling.  

      After a decade+ of moving to the cloud, I didn't think I would think much any more of the days of managing my DAG and the other in-house procedures to keep a clean ship running.   I'm sure I'm not the only one enjoying the features in M365 that you cannot "turn off" even if you do not want them.  

      I wonder 🤔if there will be (or is) a trend to go back on-prem from cloud to terra... and if it would be called "raining"  😜.

    • Nino_Bilic's avatar
      Nino_Bilic
      Icon for Microsoft rankMicrosoft
      Oct 17, 2025

      First off, let me just say that I agree that you should absolutely do what is right for your business, whatever that ends up being. Software landscape has been changing and those changes might mean that some might have to look for alternatives.

      On licensing of Exchange SE, there is a section in the following post that talks about 3 paths organizations have: Upgrading your organization from current versions to Exchange Server SE | Microsoft Community Hub. Since Exchange 2019, Exchange Server requires addition of Software Assurance (SA) as a subscription component and that remains the same (there is no licensing change between Exchange 2019 and Exchange SE).

      The last thing I wanted to mention is that - while Exchange SE is on Modern Lifecycle Policy, we have already committed to supporting it until at least 2035 and wrote about it here: Additional Support for Select Server Products Following Modern Lifecycle Policy - Microsoft Lifecycle | Microsoft Learn

  • STGAdmin's avatar
    STGAdmin
    Copper Contributor
    Oct 16, 2025

    New to the blog. Sorry if this has been covered in another blog that I have not found. We have a client that we are in the process of migrating to Exchange Online, they have Exchange 2016. We inherited the network, so we need a few months to plan the migration. How can we get enrolled in the Exchange Extended Security Update program?

  • niehweune1's avatar
    niehweune1
    Copper Contributor
    Oct 15, 2025

    What are the plans re. transport-based enforcement for customers still using Exchange 2016/2019?
    With Exchange 2019 being in scope since February (if I remember correctly), does this mean Exchange online will now start throttling and blocking mails from these servers, with a 100% block in 90 days?
    Or is there a separate timeline related to the release of CU's for SE?

    • Nino_Bilic's avatar
      Nino_Bilic
      Icon for Microsoft rankMicrosoft
      Oct 15, 2025

      Unknown; we do not have exact date when we plan to start throttling/blocking servers that are fully up to date when E2016/E2019 went out of support. We do not use this as a way to get people to upgrade to Exchange SE. We use it to nudge customers who are significantly out of date, and that definition can change based on what happens in security landscape after E2016/E2019 went out of support. So - there might be reasons to throttle/block E2016/E2019 if they are not on ESU updates before April 2026, but right now we are not planning on doing so.

      We typically have a pretty generous number of updates that we do not block, even today, but a significant vulnerability might change our timeline. Either way, when throttling/blocking comes for Exchange 2016/2019 (up to date as of yesterday's updates) - which will happen someday, there will be a standard 90 day process, yes.