Month-End Variance Reconciliation: From Ten Days to Three

Illustrative scenario—not a client case study.

The Close Was Taking Longer Every Month

The manufacturer operated two production lines with MES capturing output, scrap, and downtime. ERP held work orders, material consumption, and cost allocation. Finance needed production data to close the books. The plant manager needed cost data to explain variances.

Every month, the same pattern: Finance requested production figures. The plant provided spreadsheets. The numbers did not match. Material consumption in MES did not align with ERP backflushes. Scrap was recorded at different times in different systems. Yield calculations used different denominators. The finance controller and plant manager spent five to ten working days reconciling before the close could be signed off.

Overtime increased. The close deadline drove stress. Leadership assumed the problem was system integration. A diagnostic was commissioned to identify what was blocking a faster close.

Does This Sound Familiar?

Interviews revealed consistent themes:

• “We don’t know which scrap figure is correct until we manually compare.”
• “Material consumption is sometimes estimated, sometimes actual—it depends who entered it.”
• “Work order status in MES and ERP are out of sync for days.”
• “Finance adjusts at month-end. We never fully document why.”

What the Diagnostic Examined

1. MES-ERP handoff — What data flows, when, and with what validation
2. Variance definitions — How scrap, yield, and material consumption are calculated in each system
3. Reconciliation process — Who does it, what logic they use, and whether it is documented

1. The Handoff Was Undefined

ERP sent work orders to MES. MES was supposed to return actual production, material consumption, and scrap. In practice:

• Work order completion in MES did not always trigger ERP backflush on the same day
• Scrap was recorded in MES at the machine; it was also entered manually in ERP for some products
• Timing differences meant that at month-end, MES showed one set of figures and ERP showed another

There was no documented definition of which system was authoritative for which figure. No one owned the handoff. Reconciliation was the plant manager and finance controller negotiating until the numbers “close enough.”

2. Definitions Diverged Between Systems

Scrap was the largest variance driver. In MES, scrap was recorded by product and shift. In ERP, scrap was sometimes entered by work order, sometimes by general journal. The two were not reconciled before close—they were adjusted.

Yield was calculated differently: MES used actual output vs planned; ERP used standard vs actual for cost. When leadership asked “what is our yield?,” the answer depended on which report they looked at.

Material consumption suffered the same problem. MES had real-time consumption from the line. ERP had backflushed consumption, often with manual overrides for rework or spillage. No single definition existed for “actual material consumed.”

3. Reconciliation Logic Lived in One Person’s Head

The reconciliation was done in a spreadsheet maintained by the finance controller. It matched MES exports to ERP figures, applied adjustments, and produced variance commentary. The logic was not documented. When the controller was absent, no one could replicate it. Adjustments had no clear traceability to source.

Root Causes

• No agreed definition of scrap, yield, or material consumption
• No assigned owner for the MES-ERP handoff
• No documented reconciliation process or validation rules
• No single authoritative record when systems disagreed

Integration would not fix this until governance was clarified.

What Changed After the Diagnostic

Before any system changes, the manufacturer:

1. Defined the authoritative record — For production quantities, scrap, and material consumption, MES was designated as the source of truth. ERP would receive data from MES on a defined schedule. Manual overrides in ERP required approval and documentation.

2. Standardised definitions — Scrap, yield, and material consumption were defined in a single document. MES and ERP configurations were aligned to these definitions. Existing discrepancies were documented and resolved over one close cycle.

3. Assigned handoff ownership — The plant manager was made accountable for MES data accuracy by a defined cutoff time. Finance was accountable for ERP cost allocation. A single handoff point and validation checklist were documented.

4. Documented the reconciliation process — The reconciliation logic was captured in a procedure. Validation rules were written down. A secondary review step was added. The process could be replicated if the controller left.

The Time Outcome

The first close after these changes took six days instead of ten. Within three months, with refinement, the close was consistently completed in three days. The time savings came from:

• Fewer back-and-forth requests between finance and plant
• Clear rules for when to adjust vs when to correct at source
• Documented logic that allowed parallel work instead of sequential dependence

If a similar pattern exists in your environment — production figures that require manual reconciliation, definitions that vary between finance and operations, or a close that depends on one person’s spreadsheet — the starting point is understanding where ownership and definitions are missing, not replacing systems.

See Manufacturing Data Strategy for the governance framework, or Production and Operational Data Strategy for how MES-ERP handoffs are addressed specifically.

Related Resources

• Manufacturing examples
• Manufacturing Data Strategy
• Production and Operational Data Strategy