Batch traceability with a Chinese supplier
Agree a lot coding method before production, then link each finished batch to its component lots, production records, inspection result and deliveries. Keep those links when goods are split, mixed or reworked, and test them before shipment. Discuss factory implementation with Cambridge China Bridge.
Agree the traceability brief before production
Government product safety guidance identifies traceability as important for accountability. For your factory brief, define what a production lot contains, which changes create a new lot, where identifiers appear and who maintains the records. Agree access, retrieval arrangements and a retention period suited to the product and your business needs.
Ask the supplier to demonstrate its current records using an actual production run. Assign responsibility at the factory and within your buying team, and agree the record template before placing the order. Use the bulk production guide for sample and specification control; this guide adds the links needed to identify affected goods.
Give each lot a stable identity
Agree identifiers that distinguish the factory, product and production lot without relying on a purchase order or shipping date alone. Keep a register explaining each code, including its production site and dates. Do not reuse codes. Define when a component change, process change or subcontracted operation requires a separate lot or recorded subdivision.
Agree where the identifier will be marked on the product, its packaging and outer cartons, as appropriate to your handling needs. Test whether it remains legible after normal storage and handling. A barcode can carry the identifier, but the underlying record must still be readable and retrievable. A carton containing mixed lots needs a contents record identifying each lot and quantity.
Record the components actually used
For materials and components relevant to safety, function or recurring defects, capture the maker, part description, specification revision, incoming lot identifier, receipt record and incoming check result. Link the lots actually issued to each finished production lot. An approved BOM describes the intended product; it does not show which component batches the factory used.
Record substitutions, material mixing, subcontracted work and rework as they happen. Preserve the original identifiers and link any replacement components or resulting lots. If the factory cannot separate output made before and after a component change, treat the affected scope as uncertain rather than assigning a precise boundary without evidence.
| Record | Details to capture | Link to preserve |
|---|---|---|
| Incoming component | Maker, part revision, incoming lot and check result | Finished lots that consumed it |
| Production | Finished lot, site, dates, process record and quantities | Actual component lots and subcontracted operations |
| Inspection and release | Report reference, sampled lots, result and release decision | Finished lots and cartons covered |
| Delivery | Shipment reference, carton contents, quantities and recipient | Released lots dispatched and received |
Connect inspection, release and delivery
Ask the inspector to record the lot identifiers visible on sampled goods and cartons, photograph them and state which lots the report covers. A report headed only with the order reference leaves uncertainty when the order contains different production runs. Use quality inspection explained to agree the inspection method separately from the traceability check.
Keep the release decision against the inspected lots. After sorting or rework, link the original failure, corrective work and subsequent inspection rather than replacing the earlier report. At dispatch, reconcile released lots with packing records and actual carton markings. Record split shipments and link each delivery to its recipient; retain those links through warehouse repacking and onward business deliveries.
Test the chain before accepting it
Choose a packed product and ask the factory to retrieve its production record, component lots, inspection evidence and dispatch allocation. Then choose a component lot and ask which finished lots used it and where those goods went. Compare the records with physical markings and reconcile quantities produced, rejected, held, reworked and dispatched.
If links are missing, hold shipment while the supplier resolves them. Where affected goods cannot be separated reliably, widen the containment scope. Keep buyer-accessible copies and a record of corrections, then repeat the exercise after changes to coding or production. For action after a safety problem reaches customers, see recalling imported products.
Frequently asked questions
Is a purchase order number enough for batch traceability?
An order can contain different production runs and component lots. Use separate lot identifiers and map them back to the order, inspection records and deliveries.
What component records should I ask a Chinese factory for?
Ask for the maker, part and revision, incoming lot, receipt and check records, and the finished lots that used it. Prioritise components relevant to safety, function and recurring defects.
How do I trace a batch split across shipments?
Keep the production lot identifier and record the cartons, quantities, shipment references and recipients for each dispatch. Preserve the links when your warehouse repacks or forwards goods.
How can I check whether factory traceability works?
Trace a packed product back to its component lots, then trace a component lot forward to finished goods and deliveries. Check physical markings and quantity reconciliation, not just the supplier's template.