Guide · AI
Dynamics NAV End of Support: Which Version Ends When and What It Means
Extended support for Dynamics NAV 2017 ends on January 11, 2027. As of early November 2026, that is just over nine weeks away. The key question is not whether the system still starts afterwards: it does. The question is how you justify an ERP system without vendor support to leadership, your auditors and IT security, and how long you want to keep doing that. This guide covers the dates, what really happens on the deadline, and what a controlled bridge period looks like.
The dates at a glance
Microsoft publishes lifecycle dates for its products. For the NAV and AX versions still in common use:
Dynamics NAV 2015
End of mainstream support: Jan 14, 2020
End of extended support: Jan 14, 2025, expired
Dynamics NAV 2016
End of mainstream support: Apr 13, 2021
End of extended support: Apr 14, 2026, expired
Dynamics NAV 2017
End of mainstream support: Jan 11, 2022
End of extended support: Jan 11, 2027
Dynamics NAV 2018
End of mainstream support: Jan 10, 2023
End of extended support: Jan 11, 2028
Dynamics AX 2012 R3
End of mainstream support: Oct 12, 2021
End of extended support: Jan 10, 2023, expired
If you run NAV 2015 or 2016, you are already past support. AX 2012 R3 has been out of support since early 2023. NAV 2018 is the last version with time left, and that ends on January 11, 2028.
What extended support still covers and what it does not
Extended support is regularly overestimated. In this phase, Microsoft only provides security updates at no cost. No longer included:
• free hotfixes for functional bugs without a security impact
• design changes and new features of any kind
• free support requests at the previous level
According to Microsoft, tax and regulatory releases are only available to customers with an Enhancement Plan or Software Assurance. In practice, a change in sales tax rules or e-invoicing formats is something you or your partner have to implement, test and document. Once extended support ends, security updates stop too: there will be no patch for newly reported vulnerabilities.
Why "it still runs" is the wrong question
An ERP system without vendor support is not just a cost question. It is a question of responsibility. In our experience, three parties ask about it:
• IT security, because every newly disclosed vulnerability stays open and the stack underneath, SQL Server and Windows Server, has its own lifecycle.
• Your auditors, if your ERP is part of internal controls and the question of maintenance and change management comes up.
• Leadership, who ultimately owns the risk and should know that it exists.
An expired version is not an automatic finding. It becomes a problem when nobody noticed.
The time buffer you no longer have
Replacing an ERP system covers process discovery, design, data migration, user testing, training and a cutover that does not interrupt operations. Twelve months or more is a realistic frame. Nine weeks is not.
If you are on NAV 2017 today, you are no longer deciding whether you will meet the deadline. What you decide now is how you bridge the gap: controlled, documented and with a clear target, or unnoticed. A controlled bridge means:
1. A risk assessment for running without vendor support, with named safeguards such as network segmentation, tightly limited access and stronger monitoring.
2. A dated target plan for the replacement, approved by leadership, with milestones and budget.
3. A maintenance contract with a partner who can demonstrably keep supporting the system while it runs.
4. An inventory of customizations and integrations, so the replacement does not start from zero.
These four points take a few weeks and answer the question that would otherwise be asked later.
What happens on the deadline and what does not
On January 11, 2027, the system does not switch off. Licenses stay valid, data stays accessible, and your processes run on January 12 just as they did on January 10. What actually happens is slower and more certain:
• Newly disclosed vulnerabilities get no patch. The gap to the current security level grows every month.
• The stack underneath ages on its own schedule. Windows Server 2016, for example, reaches end of support one day after NAV 2017.
• Skilled people get harder to find. NAV developers with C/AL experience have mostly moved to Business Central.
• Partners drop out, usually on short notice.
The pressure does not hit on the deadline but in the months after, at a point you do not get to choose.
When an extension is defensible
Not every NAV installation has to be replaced right away. If your system runs stably, has no open issues, access is tightly limited and no ERP-related legal change is coming, running it for a defined period can be the right decision, as long as it is a decision and not an oversight.
The difference is on paper. A documented risk decision names the limitation, assesses the consequences, lists safeguards, sets a date for review and is approved by leadership. Once you decide to replace it, the next question is the target system, usually Business Central or Finance & Supply Chain. The path from NAV to Business Central is covered in From Dynamics NAV to Business Central.
Where AI agents help here
Most of the time in a replacement goes not into technology but into the inventory: which customizations exist, what were they for, which data is clean? That is exactly where AI agents help.
• Inventory customizations: An agent reads the C/AL objects and existing documentation and proposes the business purpose of each customization. Your team confirms or corrects. Weeks become days.
• Check data quality: Duplicates among customers, vendors and items, incomplete master data and contradictory records are found automatically and listed for cleanup.
• Monitor the bridge period: A workflow reports new security advisories for your stack and reminds you of the next review.
The decision stays with you. The agents take over the collecting and checking.
How aenuma helps
aenuma combines Dynamics experience with AI. We support the inventory, solution design and steering your implementation partner, and use AI agents where they noticeably shorten the work. More on our services page.
Frequently asked questions
Can I keep using Dynamics NAV 2017 after January 11, 2027?
Yes. The license stays valid and the system keeps running. Microsoft only stops security updates and support. Continuing to run it is a risk decision that you should document and justify.
How long does a replacement realistically take?
Plan for twelve months or more from decision to stable operations, depending on data quality, number of sites and the amount of customization in the legacy system.
What about Dynamics NAV 2018?
Extended support ends on January 11, 2028. If a project starts in mid-2027, that may not cover a full replacement. Start planning now; implementation can follow later.
Which version of Business Central is the target?
From NAV, the supported path runs through Business Central version 14 and version 25 to the current version 29. Online is the target for most companies. Details in From Dynamics NAV to Business Central.
Sources
Ending Support in 2027 (Microsoft Learn)
Ending Support in 2028 (Microsoft Learn)
Dynamics NAV 2017 lifecycle (Microsoft Learn)
Dynamics NAV 2018 lifecycle (Microsoft Learn)
Lifecycle FAQ, Dynamics (Microsoft Learn)
Fixed Lifecycle Policy (Microsoft Learn)
Supported upgrade paths to Business Central releases (Microsoft Learn)
By Joshua Schütt, founder of aenuma. Last updated: November 2026.
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