NAV 2013 to Business Central: The Complete Migration Guide

If your business is still running Microsoft Dynamics NAV 2013, you are operating on software that is over a decade old. Microsoft ended mainstream support for NAV 2013 in January 2018 and extended support concluded in January 2023. That means no security patches, no regulatory updates, and no fixes if something breaks. The question is no longer whether you should migrate to Business Central — it is how to do it well and what to expect along the way.

This guide walks through every stage of migrating from NAV 2013 to Microsoft Dynamics 365 Business Central, from the initial assessment through to go-live and beyond. Whether you are a finance director trying to understand the project scope, or an IT manager planning the technical delivery, this guide is written to give you a clear picture of what the process actually involves.

Why NAV 2013 Is a Bigger Risk Than Most Businesses Realise

Many businesses that have been running NAV 2013 for years view it as stable. It works, it is familiar, and the team knows how to use it. That stability is real, but it comes with hidden risks that compound over time.

The most significant risk is security. Without Microsoft issuing security patches, any vulnerability discovered in NAV 2013 remains permanently unpatched. For businesses handling sensitive financial data, supplier information, or customer records, this creates genuine exposure.

The second risk is regulatory. Making Tax Digital requirements, changes to VAT rules, updated HMRC reporting standards — none of these will be reflected in NAV 2013 updates, because there are no more updates. Businesses using NAV 2013 for VAT submissions are increasingly relying on workarounds or manual processes that introduce compliance risk.

The third risk is integration. The broader Microsoft ecosystem has moved on substantially. Power BI, Power Automate, Microsoft Teams, Copilot — none of these integrate natively with NAV 2013. Businesses on NAV 2013 are effectively locked out of the modern Microsoft stack that the rest of their organisation may already be using.

What the Migration from NAV 2013 to Business Central Actually Involves

A NAV 2013 to Business Central migration is not a software upgrade in the traditional sense. Business Central is a fundamentally different product — cloud-based, subscription-licensed, and built on a modern web architecture. The migration involves moving your data, replicating or replacing your customisations, and configuring Business Central to support your specific business processes.

The main workstreams in a NAV 2013 migration project are:

• Discovery and assessment: Understanding your current NAV 2013 environment, including all customisations, integrations, and third-party add-ons.
• Data migration: Extracting and cleaning master data and historical transactions for import into Business Central.
• Customisation review: Determining which NAV 2013 customisations need to be rebuilt, which can be replaced by standard BC functionality, and which are no longer needed.
• Configuration: Setting up Business Central to match your chart of accounts, approval workflows, user roles, and operational processes.
• Integration rebuild: Reconnecting any external systems — payroll, CRM, ecommerce, EDI — that currently integrate with NAV 2013.
• Testing: Validating that data, processes, and outputs match expectations before go-live.
• Training and go-live: Preparing your team and managing the cutover from NAV 2013 to Business Central.

Data Migration: What to Expect

Data migration is consistently the phase that takes longer than expected and requires the most preparation on the client side. NAV 2013 data structures differ from Business Central, and the migration is not a simple export and import. There are field mapping differences, data quality issues to resolve, and decisions to make about how much historical data to bring across.

For most businesses, the pragmatic approach is to migrate open transactions and a defined period of historical data — typically two to three years — and to archive the rest. NAV 2013 can be kept available in a read-only capacity for historical reference after go-live if required, which avoids the need to migrate everything and reduces project risk and cost.

Master data — customers, suppliers, items, chart of accounts, bank accounts — needs to be reviewed and cleaned before migration. This is an opportunity to remove duplicates, update contact information, and rationalise your item list. Businesses that invest time in data quality before migration consistently have smoother go-lives than those who defer it.

Handling Customisations from NAV 2013

NAV 2013 customisations were typically built in C/AL, a proprietary development language. Business Central uses AL extensions, which are developed differently and follow a different deployment model. NAV 2013 customisations cannot be directly imported into Business Central — they need to be rebuilt.

Before investing in rebuilding every customisation, it is worth reviewing whether Business Central's standard functionality now covers what was originally built custom. Business Central has advanced considerably since 2013, and in many cases what required a customisation in NAV 2013 is now available out of the box or can be addressed through configuration.

For customisations that genuinely need to be rebuilt, the AL extension model has advantages. Extensions are isolated from the core Business Central application, which means they survive Microsoft's biannual platform updates without needing to be rebuilt each time. This is a significant improvement over NAV 2013, where customisations often created upgrade difficulties.

Cloud vs On-Premise: The Deployment Decision

Business Central is available as a cloud SaaS product (Business Central Online) and as an on-premise deployment. For most businesses migrating from NAV 2013, Business Central Online is the recommended route. It removes the infrastructure overhead, receives automatic Microsoft updates, and provides the native integrations with Power BI, Copilot, and Power Platform that on-premise deployments do not support.

On-premise Business Central exists primarily for organisations with specific data sovereignty requirements, heavily customised environments where update management needs to be controlled, or businesses in regulated sectors with restrictions on cloud hosting. If none of these apply, the cloud deployment is the better long-term choice.

How Long Does a NAV 2013 Migration Take?

Project timelines vary significantly depending on the complexity of the NAV 2013 environment, the extent of customisations, the number of integrations, and the availability of client-side resource during the project. A general range for a NAV 2013 migration is three to nine months from kick-off to go-live.

Simpler environments — those with limited customisations, clean data, and few external integrations — sit at the lower end of that range. More complex environments, particularly those in manufacturing or distribution with extensive customisation, production planning tools, or EDI integrations, will typically take longer.

The most common causes of delays are data quality issues discovered during migration, scope changes introduced mid-project, and delays in client-side resource availability for testing and training. A well-run discovery phase at the start of the project identifies most risks early, which is why the quality of that initial phase matters so much.

What Business Central Gives You That NAV 2013 Does Not

The practical improvements from migrating to Business Central are substantial. The most visible is access to the modern Microsoft ecosystem. Business Central's native Power BI integration gives finance teams real-time dashboards that would have required significant custom development in NAV 2013. The Outlook integration means purchase orders, sales quotes, and customer records are accessible directly from email without switching systems.

Copilot features — now embedded into Business Central — automate a range of routine finance tasks including accounts payable processing, cash flow forecasting, and late payment prediction. These capabilities simply do not exist in NAV 2013.

For manufacturing businesses, the production planning tools in current Business Central versions are considerably more capable than NAV 2013's equivalents, particularly when combined with add-ons such as visual scheduling tools that integrate directly with the Business Central production module.

Choosing the Right Partner for Your NAV 2013 Migration

The quality of your implementation partner has more impact on project outcomes than almost any other factor. NAV 2013 migrations require specific expertise in legacy NAV environments — understanding old customisation patterns, knowing how to handle C/AL to AL migration, and having experience of the data migration tools that work reliably with older NAV versions.

NetMonkeys has delivered NAV-to-Business Central upgrades from every version from 2009 to 2018. When evaluating partners, ask specifically about their experience with your version of NAV, how they handle customisation assessment, and what their data migration methodology involves. Read our guide on how to choose a Business Central implementation partner for a full breakdown of what to look for.

The Cost of Waiting

The longer a business remains on NAV 2013, the more the migration cost increases. Customisations accumulate. Data quality deteriorates. The gap between NAV 2013 and current Business Central widens. The team that built the original customisations may no longer be available. And the security and compliance risks grow with every passing year.

There is no version of this calculation where waiting is the cheaper option. Businesses that migrate sooner benefit from more years of platform improvements, incur migration costs while the gap is smaller, and eliminate the ongoing risk of operating unsupported software.