Implementing an ERP system is often seen as a step toward rationalisation. Yet once in production, operating costs tend to remain high and can even be difficult to anticipate. Maintenance, support, user requests, and data entry errors all contribute to turning what should simplify operations into a continuous cost centre if not properly managed.
Here are the six main reasons behind these high costs and how to better anticipate them:
1. An evolving system
An ERP is not a project that is “closed” once it goes live. It is a dynamic system that requires regular updates, functional changes, regression testing and sometimes full process redesigns.
With each business or regulatory change, the system must adapt. This could involve adding new features, adjusting validation rules, updating reference data or evolving security protocols.
Each change draws on resources: consultants, system admins, key users, and feeds into the organisation’s operational budget.
💡 Tip: Set a multi-year adaptive budget that is distinct from day-to-day system maintenance. This will help absorb necessary changes without having to manage them in a rush.
2. Dependency on internal and external resources
An ERP system’s performance relies on a chain of skilled contributors that is often hard to stabilise. Between internal profiles (business key users, system admins, support teams) and external partners (integrators, vendors), interventions multiply.
Even a small change to a workflow or validation step often requires the input of a specialised consultant, with long lead times and high costs.
At the same time, the loss of internal knowledge due to staff turnover, overload or mobility increases reliance on external resources.
💡 Tip: Invest in training functional key users internally. Document key workflows to reduce reliance on a few individuals.
3. Technical complexity often underestimated
ERP systems rarely operate in isolation. They are usually connected to other tools like payroll, HRIS, CRM, document management, business-specific apps or BI platforms.
This technical ecosystem, often based on custom interfaces, creates fragility.
Each time a connected system is updated, the interfaces must be reviewed, tested and adjusted. A single failure in data flow can disrupt the entire chain.
On top of that, synchronisation rules between systems (timing, dependencies, file formats) must be tightly managed to avoid data loss or inconsistencies.
💡 Tip: Maintain a clear map of inter-application flows and automate alerts on import/export errors so you can take preventive action.
4. Training and user support
An ERP system that is not well understood is not well used. Every wrong entry, omission or misinterpretation results in errors to correct, blocked workflows and support intervention.
In many organisations, training is heavily front-loaded during deployment, then neglected.
As a result, users forget, improvise or develop their own workarounds, which stray far from recommended best practices.
💡 Tip: Build a continuous training plan with short, contextualised, targeted formats embedded directly into the ERP. Involve managers to help turn best practices into collective habits.
5. Constant adaptation to business changes
Each business change, such as a new subsidiary, a product launch or a governance shift, has direct consequences on the ERP. These could include adding analytical structures, changing approval workflows or adjusting access profiles.
If the system is not adapted in time, users will create their own workarounds using Excel, macros or unofficial tools, which weakens processes and adds hidden costs.
💡 Tip: Set up cross-functional ERP governance involving business teams to assess, prioritise and plan changes smoothly.
Incorrect data in an ERP system is never harmless. A wrong item reference, incorrect date or misapplied cost centre can:
- result in a non-compliant purchase order
- skew strategic reporting
- cause accounting inconsistencies
These errors are not always spotted immediately and can take hours or days to resolve.
On top of that, non-standard usage, such as copy-pasting old documents or bypassing workflows, creates structural discrepancies over time.
💡 Tip: Identify the most sensitive fields and implement control mechanisms early in the process. Use support and quality data to locate the root causes. Add help bubbles next to fields to guide users on correct data entry.
Conclusion
ERP operating costs stem from the very nature of the system: it is evolving, cross-functional, interconnected and heavily reliant on the people who use it.
Rather than trying to cut these costs blindly, it is better to plan for them wisely: train, document, govern, automate and measure.
By turning your ERP into a living, well-managed and user-adapted system, these costs become long-term investments instead of burdens.
Want to go further? Discover Why ERP alone is not enough to boost productivity
