The Customer Changed the Build. Did the Commercial Model Change With It?
Late BOM revisions, substitute approvals, extra inspection, new packaging or changed delivery can alter EMS cost after the original quote. Change control should connect the technical revision with its material, labor, scrap and logistics consequence.
The short answer
A customer or engineering change becomes a commercial event when it alters material, labor, test, inventory exposure or delivery cost. The technical ECN should therefore trigger a cost-impact review before the new baseline disappears into normal production.
The same question belongs to the wider The EMS Quote Looked Profitable. Where Did the Margin Go? operating picture: customer-change cost recovery has to remain connected to the decisions made before and after it, rather than becoming a separate local control.
Preserve the quoted baseline
Know which BOM revision, sources, process and delivery assumptions supported the original price. Classify the change origin. Customer change, supplier-driven substitution, internal engineering correction and manufacturability improvement can have different commercial treatment. Identify obsolete material. A component replacement can leave open PO, warehouse stock, kits and WIP exposed. Measure new component cost. The replacement part may have different unit price, MOQ, lead time or approved-source restrictions. Include rework of WIP. Existing assemblies may need component replacement, reprogramming or additional inspection. Include test changes. New firmware or design behavior can require fixture, script, limit or cycle changes. Include tooling and NRE. The revision may need new stencil, fixture, programming or engineering validation.
Include packaging changes. Customer labeling, packing or accessory changes can add material and labor after quotation.
Include delivery consequence
A late revision may create premium freight, partial shipment or schedule disruption. Use effectivity to define cost population. The cost depends on which POs, stock, WIP and finished goods fall under the new revision. Separate recoverable and absorbed cost. Commercial teams may choose to absorb some changes. Preserve the decision. Create a change-cost summary. For significant revisions, present material, WIP, NRE, labor and logistics impact together. Avoid charging without evidence. A clear cost bridge supports a better customer conversation than a generic change fee. Avoid absorbing without visibility. Free customer service is still a business decision and should not disappear from program profitability. Update future standards. Once the change becomes the new baseline, update BOM, routing, test and cost assumptions.
Review repeat change behavior. Programs with frequent late revisions may need different commercial terms or change cutoffs.
Use a commercial freeze point
As production commitment increases, changes become more expensive. Define when customer changes trigger stronger review—for example after PO release, kitting, SMT start or completed production. Separate unavoidable and avoidable obsolete stock. Some obsolete material is an unavoidable consequence of a customer change. Some results from overbuy or weak effectivity control. Preserve the cause because the corrective action differs. Track unbilled change burden. Not every recoverable change is actually invoiced. Compare approved recovery with billed/collected outcome where the commercial process supports it. Review chronic change customers. If one program repeatedly changes BOM or delivery after release, use the history to revisit lead time, liability terms or change procedures.
Create a cost-impact checkpoint in ECN workflow. For changes above a threshold, require a quick review of material, PO, WIP, tooling, test and delivery impact before implementation. This does not need to delay every minor change; it targets revisions that can materially affect margin. Use effectivity to protect old and new economics. A change can apply from a specific work order, date or serial. Costs before and after effectivity should not be mixed. This makes obsolete-stock and rework exposure easier to explain. Capture open-PO cancellation cost. Suppliers may charge cancellation, restocking or NCNR liability when a component changes. Include those commitments in the commercial bridge.
Review customer approval lag. If the customer takes time to approve a substitute or revision, the factory may incur expedite or schedule cost later. Preserve this timing when discussing recovery.
Separate design correction from customer enhancement
A change fixing an internal engineering error is different from a customer-requested feature. The cost may be operationally similar but commercial responsibility differs. Use change history in annual pricing. Programs with frequent revision activity can justify different change terms, NRE treatment or liability rules during renewal. Include finished-goods exposure. A late change may affect already completed stock. Decide whether it can ship, be reworked or becomes obsolete. This can be a larger cost than raw material. Close change economics after implementation. Once the new revision is stable, compare estimated impact with actual cost. This improves future change-order decisions and prevents inflated or understated recovery assumptions.
Use change-cost thresholds by lifecycle stage. A small BOM change before purchasing may have little cost. The same change after kitting or completed production can be expensive. The review threshold should reflect where the job is in its lifecycle, not only the engineering size of the change. Connect customer change to delivery re-promise. If the revision changes material or process, the original date may no longer be feasible. Recalculate the operational promise instead of keeping the old date and creating an unplanned expedite. Preserve old-revision inventory usability. Some superseded material can still be used for service, other product or old-revision orders. Do not scrap automatically. Engineering disposition should define allowed reuse.
Use rework feasibility before accepting late change. A customer may assume existing WIP can be converted. Manufacturing engineering should confirm whether the change can be reworked reliably and whether traceability remains valid.
Include quality-validation cost
A new component or process may require first-article, additional inspection or pilot validation. That cost belongs to the change decision when it is incremental. Review quote impact for future releases. Even if the current change cost is absorbed, the new revision may have a permanently higher recurring cost. Update the next release or annual price basis so the margin leak does not continue. Connect change to supplier commitments. A new component can create a new MOQ while the old component remains under NCNR PO. Both sides of the transition belong in the commercial impact. Use change history to improve customer collaboration. Evidence of repeated late changes can support earlier design freeze, stronger approval deadlines or clearer liability terms. The goal is a smoother shared process, not simply more charges.
Use technical approval and commercial approval as separate checkpoints. Engineering can approve the technical change while commercial teams still need to decide price, liability or delivery. Keeping the decisions separate avoids delaying urgent engineering work while still protecting the business from silently absorbing material cost. Preserve change-request timing. Record when the customer or engineering change was received relative to purchasing, kitting and production. Timing is key evidence when explaining why the same technical change created very different cost on different jobs.
Review absorbed change cost at program level. A single absorbed change may be good service. Repeated absorbed changes can become a structural margin leak. Aggregate the pattern by program so account teams can decide whether the commercial model still reflects the actual service.
This history also strengthens future customer discussions because the organization can show how timing, revision effectivity and already-committed material created the cost instead of presenting a generic surcharge. Where the same pattern repeats, the account team can move from one-off negotiation to clearer change-control terms.
It also helps distinguish customer-driven revision cost from internal implementation delay, so the company can improve its own execution without automatically attributing every margin impact to the customer.
This matters commercially.
What management should measure
Track customer/ECN changes with material impact, obsolete inventory, open-PO exposure, rework cost, new tooling/NRE, test changes, premium logistics, recovered customer charges, absorbed change cost and margin change by program.
A practical review
Choose one major ECN from the last month. Reconstruct the original quote baseline and list every affected PO, inventory position, WIP unit, test step and shipment. Then compare total cost impact with what was recovered or deliberately absorbed.
Where Epicor Mars fits in customer-change cost recovery
For customer-change cost recovery, the key system-design question is how to keep enterprise control and electronics-specific execution on the same operating thread. Epicor provides the enterprise-grade ERP foundation for customer orders, purchasing, inventory, planning, costing, finance, approvals and governance. Epicor Mars extends that foundation with the EMS industry context needed at the point of work, including BOM and revision context.
That connection is directly relevant to The Customer Changed the Build. Did the Commercial Model Change With It?. Late BOM revisions, substitute approvals, extra inspection, new packaging or changed delivery can alter EMS cost after the original quote. Change control should connect the technical revision with its material, labor, scrap and logistics consequence. When the Epicor Mars execution record stays tied to the Epicor work order, material and customer context, management can compare the business commitment with what the factory actually executed without maintaining a second source of truth.
For customer-change cost recovery, that complementary positioning is the point: Epicor remains the enterprise-grade foundation, while Epicor Mars adds the EMS workflows needed to make this particular control operational on the factory floor. Explore Epicor Mars for electronics manufacturing.
Frequently asked questions
Does every ECN require repricing?
No. Only changes with meaningful commercial impact need a pricing decision.
Who should own the cost review?
Engineering identifies technical impact; purchasing, operations and commercial teams contribute the economic consequences.
What if the business chooses to absorb the cost?
Record it so program profitability remains accurate.
Why use effectivity in cost analysis?
Because only the transactions and WIP exposed to the changed revision should be included.