Extensions in Business Central: Why They Matter (and Why They’re Not Like the Old Days)
- Elliott Clark Consulting
- 1 day ago
- 6 min read
From “Anything Goes” Customization to Modern Extensions
If you’ve been around Microsoft ERP long enough, you’ll remember the old days of Microsoft Dynamics NAV (formerly Navision). Back then, we literally sold the product on its ability to be customized. The message was: “Tell us what you want, and we can change the code to make it happen.”
And boy, did we ever. Companies built Frankenstein versions of NAV—heavily customized, incredibly complex, and nearly impossible to upgrade. Each new release felt less like an update and more like a root canal. Some organizations ended up stuck, unable to move forward without a complete reimplementation.
Fast forward to today: Microsoft Dynamics 365 Business Central is a different world. While Business Central is the evolution of Dynamics NAV and much of the historical power is still there including huge flexibility, customization is no longer the starting point—it’s the last resort.
Why? Because Business Central already comes with deep functionality, powerful integration to the Microsoft ecosystem, and a thriving marketplace of third-party apps. Before you even think about custom code, you can often solve challenges with:
Out-of-the-box capabilities that go far deeper than QuickBooks or spreadsheets.
Microsoft Power Platform for automation, workflows, and reporting without touching the codebase.
AppSource, Microsoft’s official marketplace, where vetted partners (like us—see our AppSource profile) publish tested, supported solutions.
That’s where extensions come in.
What Exactly Is an Extension?
In simple terms, an extension is a layer that sits on top of Business Central without altering the original codebase. Think of it like an app on your smartphone: it adds functionality, but it doesn’t rewrite iOS or Android itself.
This “side-by-side” design matters because:
Future-proofing: Extensions don’t break when Microsoft ships updates. Your core system stays intact.
Easier upgrades: No more holding your breath every time a new release comes out.
Flexibility with safety: You still get to meet your unique business needs, but without painting yourself into a corner.
In other words, extensions let you have your cake and eat it too—the adaptability companies loved in NAV, but with the maintainability and scalability modern ERP demands.
Why Extensions Are Important for Your Business
For most small to mid-sized manufacturers and distributors, extensions strike the perfect balance:
Agility without chaos: Your business is unique—no two manufacturers run exactly the same way. Extensions let you add the exact functionality you need without destabilizing the system.
Lower total cost of ownership (TCO): With fewer customizations buried in the core code, your upgrade and support costs drop dramatically over time.
Scalability: As you grow, extensions can be added or removed as needed. You’re not locked into a permanent Frankenstein.
Best-of-breed solutions: Many industry-specific needs are already solved by certified apps in AppSource. Why reinvent the wheel?
When Do You Actually Need Custom Extensions?
Here’s the truth: most businesses don’t need heavy customizations anymore.
Between built-in features, AppSource, and the Power Platform, most of your needs can be met.
But there are times when a custom extension makes sense:
You have a regulatory requirement unique to your industry.
You need to integrate with a proprietary piece of equipment or workflow.
You’ve identified a process that is truly differentiating for your competitive edge.
In these cases, an extension is still the right approach—but it’s scoped, designed, and deployed in a way that doesn’t compromise your future.
At Elliott Clark Consulting, we will always challenge you to ensure your customization requests are truly business-necessary. Customizations should never be used as a shortcut for issues that can be solved through process improvement, training, or standard features. For example, we never recommend using a customization to:
Fix training gaps (if your team doesn’t know how to use a feature or makes the same mistake repeatedly, the answer is education, not code).
Bypass existing functionality (reinventing what Business Central already does out of the box only creates long-term complexity).
Force old habits into a new system (customizing just to keep doing things “the way we always have” can limit your ability to grow).
By drawing a firm line around when extensions make sense—and when they don’t—we help you protect your investment and keep Business Central clean, scalable, and upgrade-friendly.
Keys to Success with Extensions
Here are a few tips we give every client:
Start with process, not code. Technology should support your business, not the other way around. Map your process first, then decide if extensions are really required.
Challenge the why. Press to really understand the true and clear "why" of the extension. Assure it's not just because that's how it's always been done.
Check AppSource first. Thousands of certified solutions exist—many for niche industries like chemical manufacturing, distribution, or cosmetics. Explore what’s available before building new. Caution- work closely with your partner as you evaluate and ultimately deploy AppSource apps. Most are designed to work with other apps but there could be conflicts in some processes.
Use the Power Platform. Automations, approvals, and dashboards can often solve challenges without custom coding.
Keep extensions lean. Only extend where there’s clear ROI. Avoid the “because we can” mentality that led to NAV nightmares.
Choose a partner who puts process first. Extensions should enable your growth, not burden it. At Elliott Clark Consulting, we’ll always challenge the need for code before recommending it. Notice we've mentioned that twice in this article. It matters.
Frequently Asked Questions About Extensions in Business Central
What are extensions in Business Central?
Extensions are add-on apps or customizations that sit on top of Microsoft Dynamics 365 Business Central. Unlike older NAV customizations, extensions don’t modify the base code, making them upgrade-safe and easier to maintain.
How are extensions different from customizations in Business Central?
Traditional customizations in Business Central’s predecessor (NAV) meant changing the core code, which made upgrades expensive and complicated. Extensions, by contrast, are layered outside the base system, preserving your ability to upgrade while still tailoring functionality to your business.
Do I need extensions if Business Central already has so many features?
Not always. Business Central comes with deep functionality, and many needs can be solved through AppSource apps or the Power Platform. Extensions are most valuable when you face a unique industry requirement or need a competitive differentiator.
Are extensions in Business Central expensive?
The cost of an extension depends on complexity. Many are available as low-cost, subscription-based apps in Microsoft AppSource. Custom extensions can require an upfront investment but often save money long term by reducing manual work and avoiding expensive workarounds.
When should I use a custom extension vs. AppSource?
Use AppSource if a proven solution already exists for your need. Choose a custom extension only when:
No existing app fits your requirements.
Your process is a true competitive differentiator.
You need compliance with a unique regulatory requirement.
Can extensions in Business Central break during upgrades?
Not usually—extensions are designed to be upgrade-friendly. That’s the key advantage over old NAV customizations. As long as your extensions are built following Microsoft’s standards, they typically won’t prevent you from moving to newer versions.
Who should build extensions for Business Central?
Extensions should be designed and developed by a certified Microsoft partner who understands both your business processes and Business Central’s architecture. At Elliott Clark Consulting, we take a process-first approach to make sure extensions solve real problems without creating future headaches.
The Bottom Line
Extensions are one of the most powerful reasons to choose Microsoft Dynamics 365 Business Central. They deliver flexibility without the upgrade headaches of the NAV era, giving you confidence that your ERP will evolve with your business.
Whether you need a standard app from AppSource, a Power Platform flow, or a lightweight custom extension, the key is starting with your business goals—not just the technology.
At Elliott Clark Consulting, we help manufacturers and distributors cut through the noise, align processes, and use extensions strategically—not recklessly. The result? A system that works for you today and doesn’t trap you tomorrow.
Considering a Customization in Business Central?
Before you invest in custom code, let’s make sure it’s truly necessary. At Elliott Clark Consulting, we specialize in helping manufacturers and distributors get the most from Business Central without falling into the old NAV trap of costly, upgrade-blocking customizations.
Book a Free Second Opinion Session and gain clarity on whether an extension, AppSource app, or process improvement is the smarter path forward.
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