If you run Dynamics NAV today, the move to Business Central is not one decision but two. First, will you upgrade the system you have, or start again with a fresh Business Central implementation? Second, will you run Business Central online or on your own servers? The right answer depends far more on the state of your NAV database and customizations than on the version number.
Why this matters now
Every NAV version has reached, or is approaching, the end of Microsoft support. NAV was renamed and rebuilt as Business Central, and Business Central online receives two major releases a year plus monthly updates. Staying on NAV means running an ERP that no longer gets regulatory or functional improvements, on infrastructure you have to maintain yourself.
Start with an honest assessment
Before choosing a path, gather four facts:
- Version and build: which NAV version and cumulative update you run. Older versions usually need a staged technical upgrade before data can reach Business Central.
- Customizations: how many objects have been modified, and what each change actually does. NAV customizations were made directly in the base code (C/AL). Business Central uses extensions written in AL, so every customization must be rebuilt, replaced by standard features, or dropped.
- Add-ons: which third-party add-ons you use and whether each vendor offers a Business Central version.
- Data quality: how clean your master data is, and how much history you genuinely use.
When an upgrade makes sense
An upgrade carries your existing data and setup across, with customizations converted to extensions. It usually fits when:
- Your processes still work well and users are broadly happy with how NAV runs.
- Customizations are limited and well documented.
- You need full transaction history in the new system for operational reasons.
- Your add-on vendors have Business Central versions ready.
The trade-off is that you also carry across old setup decisions, including ones that no longer suit how the business works.
When a reimplementation makes sense
A reimplementation sets up Business Central fresh, using standard features first, and migrates master data, open balances and summarized history. It usually fits when:
- NAV has been heavily modified over many years and nobody fully understands every change.
- Many customizations exist to work around features that standard Business Central now includes.
- The chart of accounts, dimensions or posting setup need to change anyway.
- The business has grown or changed shape since NAV was first configured.
The trade-off is more process design and training effort, in exchange for a cleaner system that is easier to update.
Online or on-premises?
Most NAV customers moving now choose Business Central online. Microsoft manages the infrastructure, updates and backups, and integrations use modern APIs. On-premises can still make sense where specific integrations, data residency requirements or hardware investments justify it, but it keeps the upgrade burden with you. For Canadian customers, Business Central online can be hosted in Microsoft's Canadian datacenter region, which often addresses data residency questions.
A practical way to decide
- List every customization and classify it: replaced by standard, still needed, or no longer needed.
- Count what remains in the still needed column, and estimate the effort to rebuild each as an extension.
- Compare that with the effort to redesign processes around standard features.
- Decide how much history must be live in Business Central versus available for lookup.
- Choose the path with the lower total risk, not just the lower initial cost.
In our experience the answer is often a hybrid: a fresh Business Central setup that reuses clean master data and a small number of well-proven customizations rebuilt as extensions.
Next step
Our NAV to Business Central upgrade page explains how we run these projects. If you'd like a view on your own database, request a NAV assessment and we will review your version, customizations and add-ons before you commit to a path. You may also find our GP vs Business Central process differences guide useful if your group runs both products.