From NAV to Business Central online: an overview

Many companies still run an older Dynamics NAV with customisations built up over years. Moving to Business Central online is not one action but a series of steps, and the customisations and the data take the most work. This article gives an overview of the order of the steps, what typically has to be rewritten and how the data comes across. You get a list of questions to settle before you ask for quotes. It is written for the people who have to decide scope and timeline.

Start with an honest picture of where you are

Before you choose a method, you need to know what your NAV actually contains. List the version, the number of companies, the customised objects, the integrations and the reports. Also note who uses what, and what has become habit without any real business reason.

Many findings here end as decisions to drop something. That is often the cheapest part of the project.

Two routes, and customisations that must be rewritten

Microsoft Learn describes that from Dynamics NAV you first upgrade to a version of Business Central on-premises and then migrate to online. You need to check for yourself which minimum on-premises version Microsoft requires before data can be moved directly, because the requirement changes. See the Microsoft Learn page on migrating on-premises data to Business Central online.

The other route is a fresh start, where you set up a clean Business Central and move master data and opening balances. That gives a cleaner system, but more manual work.

Business Central online does not allow direct changes to the base code. Customisations are added as extensions, either as apps from AppSource or as per-tenant extensions. Old C/AL code therefore has to be reviewed object by object.

Can standard functionality do today what you have customised?
Is there an app that covers the need?
Does it have to be built as an extension, and who maintains it when updates arrive?
Can the report be replaced by a standard report or Power BI?

Data, testing in a sandbox and go-live

In a cloud migration, data is replicated from on-premises to online with a tool that uses Azure Data Factory. It is managed from the Cloud Migration Management page in Business Central, and there is also an API. Check on Microsoft Learn which tables are included and what you have to move yourself.

Whichever method you use, decide how much history should come across. Open entries and balances are necessary. Several years of detailed entries are often only a wish, and they take up your storage quota.

Run at least one trial migration in a sandbox environment. Let key users test invoicing, purchasing, warehouse and bank reconciliation with real figures. Errors you find here cost nothing in production.

Plan the switch itself outside month-end and quarter-end. Agree who closes the old system and how long it is kept read-only.

Integrations and reports

Old integrations through files, web services or direct database access do not work the same way in the online version. Make a list of every integration and clarify whether it can use Business Central APIs or web services instead. Reports built in the old report designer often have to be rebuilt with new layouts, and many can be replaced by Excel or Power BI.

Remember things outside the system itself too, such as a bank agreement, an e-invoicing solution or an external warehouse system. All of them have to be tested against the new environment, and some suppliers need time of their own to change their setup.

Timeline and responsibility

Decide early who owns the project in the company and which key people need to set time aside. Many projects are delayed because the accountant and the warehouse also have to run daily operations.

Plan at least two trial migrations and a final reconciliation. Allow for summer holidays and financial close, and do not let go-live fall in a busy period.

Where we can help

Addverk is a new Business Central partner offering consulting at open, fixed prices. We can review your NAV, assess the customisations and plan the migration. See our implementation service and the prices page for details.