Dynamics NAV 2018 Support Ends 11 January 2028: What to Do Before Then

On 11 January 2028, Microsoft ends extended support for Dynamics NAV 2018, the last version of NAV it released. NAV 2017 goes a year earlier, on 11 January 2027. Neither date switches anything off. Microsoft has not said NAV will stop working, and a perpetual licence keeps running. What stops is security updates and paid support.

Tax and legal updates stopped earlier. They belong to mainstream support, which for NAV 2018 ended on 10 January 2023. So NAV 2018 end of life is not a cliff in 2028. The legal updates stopped almost four years ago, the security fixes stop in 14 months, and the licensing changes in 2031.

This guide is for finance and IT leads at mid-sized manufacturers, distributors and service firms in the DACH countries, the Nordics, the Benelux and the UK, running NAV 2009 to 2018 with years of customisations, often built by a partner who has since gone.

What Ends, and When

NAV 2018 follows Microsoft's Fixed Lifecycle Policy, and its dates are on the NAV 2018 lifecycle page.

Extended support, the phase NAV 2018 has been in since January 2023, means security updates and paid support. After 11 January 2028 the security updates stop. The policy allows paid support beyond that date only through the Extended Security Update programme, and Microsoft offers no Extended Security Updates for NAV.

Tax and regulatory releases need an active Enhancement Plan and come with mainstream support. Microsoft's list of NAV 2018 cumulative updates ends with Cumulative Update 60, in January 2023. Since then, no NAV 2018 local version has received new regulatory features from Microsoft: extended support for NAV 2018 does not include them.

Microsoft's July 2026 post on NAV migration options sets out the 30 April 2031 licensing changes and tells NAV customers to "begin evaluating their long-term ERP strategy now."

The platform underneath

NAV 2018's system requirements stop at SQL Server 2019 and Windows Server 2022. SQL Server 2014 and 2016 are already out of extended support, and Windows Server 2016 follows on 12 January 2027. On SQL Server 2019 and Windows Server 2022, the database stays supported until 8 January 2030 and the operating system until 14 October 2031. The ERP on top of them does not.

The Legal Changes NAV Will Not Receive

Microsoft's last regulatory update for NAV 2018 shipped in January 2023, before any of these rules took effect.

• Germany. For domestic sales between businesses, the e-invoice has been the rule since 1 January 2025, and every business must be able to receive one (an email inbox is enough), according to the Federal Ministry of Finance. Other invoices stay allowed until 31 December 2026, or until the end of 2027 for issuers with previous-year turnover of at most EUR 800,000. XRechnung and ZUGFeRD from version 2.0.1 qualify, except the MINIMUM and BASIC-WL profiles.
• Belgium. Since 1 January 2026, every Belgian business liable to VAT has to use structured electronic invoices, according to the federal e-invoicing portal. Microsoft's Business Central documentation for Belgium names the Peppol network as the channel.
• Poland. KSeF became mandatory on 1 February 2026 for companies with 2024 sales above PLN 200 million, and on 1 April 2026 for the rest, with an exception for small monthly invoice totals until 31 December 2026. Poland is not among Microsoft's NAV 2018 local versions, so a Polish NAV never got its localisation from Microsoft's NAV 2018 updates.

Business Central's German localisation lists XRechnung, ZUGFeRD and Peppol invoicing as available, and its Belgian one lists invoicing through a Peppol access point. For other countries, check the current rules with your tax adviser against what your NAV can send and receive.

Your Version and Your Route

Microsoft's upgrade paths page sets the route from NAV 2015, 2016, 2017 or 2018 in three steps: Business Central Spring 2019 (version 14), then Business Central 2024 release wave 2 (version 25), then the current Business Central 2026 release wave 2 (version 29). One sentence on that page decides most of the budget: "This path requires you convert your application from C/AL to AL."

From NAV 2009, the route through NAV 2013 also passes NAV 2018. Whatever your team calls the system, a Navision to Business Central migration from these versions is a chain of upgrades.

Version 14 is the last version that supports C/AL, and Txt2Al, the tool that converts C/AL objects to AL, ships only with it. Version 14 itself left support in October 2025, and new customers cannot use it in production: a stepping stone, not a place to stop. In version 15, AL replaced C/AL and Business Central became extension-based only. Version 25 is a required stop because since version 26 a direct upgrade from version 14 to the latest release is not supported.

Every route, including those that end in the cloud, passes through Business Central 14 on-premises.

Where the Work Actually Is

The effort grows with what was built into the system, and NAV customisations were usually built straight into Microsoft's own objects.

Customisations

In NAV, a partner customised by editing Microsoft's C/AL code: a field added to the customer table, a few lines in the posting routine. Business Central expects the base application left as delivered, with your changes beside it in extensions that respond to events.

Txt2Al converts the syntax, not the design. Microsoft calls creating those extensions "the first step, and the largest step" of the upgrade. Its NAV customisation playbook sets out the treatment: custom tables become AL tables, custom fields on standard tables become table extensions with their data moved across, changes inside Microsoft's codeunits become event subscribers, and XMLports and queries are rebuilt. Personalisations made in the Windows client are lost.

On-premises, Microsoft still allows a code-customised base application, though it strongly recommends extensions. Its on-premises licensing guide (June 2023 edition) says customers moving from NAV with customisations that are not "universal code" compatible must license an extra universal code module. Online, everything has to be an extension.

Count the modified standard objects, custom tables and fields, and which of them anyone still uses.

Reports

Every C/AL report is rebuilt in AL, as a new report or a report extension. The layouts survive: RDL and Word are both supported, and Microsoft recommends Word for document reports because RDL can be slower. List the custom reports and retire what nobody runs.

.NET add-ins

.NET interoperability exists only on-premises. Online, Microsoft points to control add-ins, Azure Functions or external APIs instead. On-premises, add-ins compiled with .NET Framework stopped working in version 22 and must move to .NET Standard. List every component, what it does, and whether its supplier still exists.

Integrations and web services

From version 29, a Microsoft page can no longer be published as a SOAP endpoint, and from version 30 not as an OData endpoint either. Microsoft's fix for SOAP is a copy of the page in your own extension. Online, integrations sign in with OAuth2 only. So a web shop, EDI link or warehouse system that calls standard NAV pages over SOAP will not survive the move unchanged. Build the inventory from the system itself (published web services, scheduled jobs, files read and written), with an owner and a decision for each.

The Windows client

The NAV Windows client was removed in version 15. Users move to the browser, the mobile apps or a desktop app. Programmatic printing went with it, so anything NAV prints without a user pressing print needs a new route. Plan training too: every screen changes.

The data

Data from tables with code customisations cannot reach Business Central online unless extensions on both sides handle them. Microsoft asks for at least one dry run of the full migration in a sandbox before cutover. Plan several. Write the migration and its checks as code you can rerun on a fresh copy of production, comparing balances and open items each time. Finance signs off when the numbers match, not when the job finishes.

Online or On-Premises

Decide this before anyone converts code: it decides what survives. Microsoft lists the features missing on-premises.

Online. Microsoft's cloud migration tool works from on-premises version 25 or later, on SQL Server 2016 or later. A full NAV to Business Central upgrade into the cloud is therefore NAV, then version 14 and version 25 on-premises, then the migration. The alternative, the Business Central 14 reimplementation tool, moves only master data, opening balances and setup from version 14 to the cloud. It is a preview, and Microsoft says preview features "aren't meant for production use".

Bridge to Cloud 3. Microsoft's partner announcement sets sign-up from 1 January 2026 to 31 December 2027: 30% off the commercial list price for a fixed, non-renewable three-year term through a Cloud Solution Provider. It applies to on-premises licences bought before 1 September 2024 with an active Enhancement Plan, and only to an online product you have not licensed before. Microsoft's partner site also mentions a Business Central migration voucher, whose terms are not public.

On-premises. Each version is supported for about 18 months (version 29, released in October 2026, until April 2028), so staying supported means an upgrade on that rhythm, with your extensions retested each time. Since April 2025, new on-premises customers can buy only subscriptions. For NAV customers moving perpetual licences across, a Microsoft community manager wrote in February 2025 that the transition policies were unchanged. We found no Microsoft end date for that right, so get your terms in writing.

A Decision Frame

Four paths are realistic.

Upgrade on-premises to the current release. Version 14, then 25, then current, on your own servers. It fits a company with .NET add-ins or integrations it cannot replace yet. You accept an upgrade roughly every 18 months, and a licence module if code stays in the base application.

Upgrade, then move online. The same route to version 25, then the cloud migration tool. Every customisation becomes an extension and every .NET add-in is replaced, so the conversion work is largest here. If you qualify for Bridge to Cloud 3, its 31 December 2027 deadline falls inside the project.

Start fresh in Business Central online. Take master data, opening balances and setup, keep the old system for reference, and rebuild only the customisations you still need. Microsoft's tool for this is a preview and starts from version 14. A company that picks a different ERP faces much the same data and integration work.

Stay on NAV for a set period. It keeps running. From 11 January 2028 it gets no security fixes, and every new e-invoicing format is your own development. This holds only with a named person who maintains it, the system kept away from the open internet, and a date when it ends.

The Next Months, Whichever You Pick

There are 14 months left until NAV 2018 end of support. If your financial year ends in December, a cutover in early January lands on year-end close, so the realistic target is a go-live in the autumn of 2027. On NAV 2017 the date is two months away: you will run unsupported for part of the project, so keep that part short.

Between now and the end of March 2027:

1. Confirm your starting point: NAV version, SQL Server and Windows Server versions, and whether your Enhancement Plan is active. Bridge to Cloud 3 and the on-premises licence transition both depend on it.
2. Secure the code. Export the C/AL objects and keep them under version control, above all if the partner who wrote them has gone.
3. Count the customisations, and which ones are in use. A count, not an impression.
4. Build the integration inventory: every web service, file exchange and .NET add-in, with an owner and a decision.
5. Check your e-invoicing obligations in each country you invoice from.
6. Decide online or on-premises before code conversion starts.
7. Book capacity: the partner, your own finance and IT people for testing, and a cutover window.

Counting back from an autumn 2027 go-live: dry runs and user testing in the summer, extension build and integration rework in the spring, analysis and decisions this winter.

Where to Get Help

What has to hold through the move is the business: invoices in the format the law now asks for, and a warehouse that keeps shipping. We work beside your Business Central partner, or directly with you when the partner who built your NAV is gone, on converting C/AL customisations to AL extensions, rebuilding integrations and reports, the data migration code and its reconciliation, and the applications around NAV that have to survive the move. That work is described on our ERP modernisation page, and legacy system maintenance covers the systems that stay where they are until you move. If you want your customisations and integrations counted before you sign an upgrade project, write to office@c9group.dev.