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NAV to Business Central: an upgrade checklist
Every NAV to Business Central upgrade quote you receive is an answer to the same five questions. Here is the checklist we run before giving a number — use it to understand your own system before you talk to any partner, including us.
1. How many custom objects do you really have?
Export your object list and split it three ways: untouched standard, modified standard, and fully custom. Modified standard objects are the expensive category — each modification must be re-expressed as an AL extension event subscriber or replaced by functionality that Business Central now ships out of the box.
codeunit 50100 "Sales Header Subscriber"
{
[EventSubscriber(ObjectType::Table, Database::"Sales Header", OnAfterValidateEvent, "Sell-to Customer No.", false, false)]
local procedure OnAfterValidateSellToCustomer(var Rec: Record "Sales Header")
begin
Rec.Validate("Shortcut Dimension 1 Code", GetDefaultDepartment(Rec."Sell-to Customer No."));
end;
}What was a direct code edit in C/AL becomes a subscriber like this in AL (GetDefaultDepartment here stands in for your own lookup procedure). Most modifications convert cleanly; the audit tells you which ones will not.
2. Which customisations does standard BC now cover?
NAV solutions accumulated custom code for things Business Central now does natively — approval workflows, email from documents, bank reconciliation imports, late payment prediction. Every such customisation you drop instead of converting is money saved twice: once in the upgrade, and again in every future maintenance hour.
3. How dirty is your data?
Posted documents with broken links, orphaned dimension entries, customers merged by hand over the years — data quality, not code volume, is the most common cause of timeline overruns. A trial migration against a database backup surfaces this early.
4. SaaS or On-Premise?
Business Central runs in both. SaaS removes infrastructure work and delivers two major updates a year automatically; On-Premise remains valid when regulation or heavy integrations demand it. Decide before the upgrade starts — it changes the migration path.
5. Who supports it afterwards?
An upgrade is not done at go-live. The first month-end close, the first VAT declaration, the first year-end — plan named support for these milestones into the project, not as an afterthought.
Considering an upgrade? We will run this checklist against your system and give you an honest, free estimation — tell us your story.