How to control factory subcontracting
Ask the supplier to disclose every outside process and production address, approve the route in writing, and require approval before changes. Link batch records to those sites and check your order while it is being made. Cambridge China Bridge can coordinate these checks through its own staff in China.
Get an order-specific process map
Our factory audit checklist covers asking about subcontracting before ordering. Turn that answer into a process map for your actual order: materials, forming, assembly, surface treatment, printing, testing and packing. Against each stage, record the company, physical address, whether work leaves the main factory, and who checks it when it returns.
Ask explicitly about overflow production, rework and subcontractors sending work onwards. A statement that the supplier makes the finished product does not tell you where its parts are processed. Keep supplier identity checks separate: see factory versus trading company.
Approve addresses and processes together
Attach the agreed process map to the order documents. Name the approved main site and outside sites, the operations each may perform, the specification revision and the person authorised to approve changes. Ask the supplier to acknowledge that moving work, adding a subcontractor or passing work onwards needs your written approval before it happens.
For each proposed change, request the reason, affected batches, equipment and process differences, inspection arrangements and access to the proposed site. Decide what samples, visits or tests you need before approving it. Assess outside sites according to how their work affects the product, especially where later inspection cannot reveal a hidden defect.
Check your order during production
Arrange access while your order is running, including to approved outside processors where relevant. Give the visitor your order reference, specification and process map. Ask them to connect the site entrance and production area with identifiable order materials, tooling, work in progress and production records. General factory photographs show capability, not who made your order.
Choose work in progress from the floor and follow its batch reference into the job card and material records. Compare the operations observed with the approved route. Check dispatch and return records for outside work. A live video can support this check, but unexplained gaps call for a visit; a final quality inspection alone cannot establish the production route.
Keep the batch trail through outside work
Ask the factory to preserve batch identity when goods leave and return. Keep records linking material lots, job cards, outside processing, quantities sent and received, rejects, rework and finished carton references. Record splits and merges so a mixed batch does not erase its origins. Use our batch traceability guide for the onward trail to customers.
For businesses selling consumer products in the UK, official guidance says to keep records identifying suppliers so product origins can be traced. For subcontracting control, extend your order records to the actual processing sites. Before release, choose a finished batch and ask the supplier to retrieve its complete route, including outside work.
Resolve gaps before releasing the order
If an address, batch record or production account conflicts with the approved map, ask the supplier to identify and separate the affected goods. Pause your shipment approval while you establish where they were made and which operations changed. Request records and access rather than accepting a replacement photo folder.
Review whether the changed route affects materials, finish, performance or existing test evidence. Agree the checks needed and record your acceptance or refusal for the affected batch. Keep any approval specific to that order and route; update the approved map before repeat production. Cambridge China Bridge can coordinate site visits and record checks through its own staff in China.
Frequently asked questions
Should I ban all factory subcontracting?
You can approve disclosed outside processes where the sites and controls suit your product. Define permitted work and require written approval before any change or onward subcontracting.
How do I check which factory made my order?
Check during production. Match identifiable order materials and work in progress to job cards, batch records and the approved site. Follow dispatch and return records for outside processes.
Does a passed inspection prove the approved factory made it?
No. It supports a decision about the goods inspected. Establishing where they were made also needs production observations and records linking the batch to the approved route.
What if my supplier will not name its subcontractor?
Treat the process as unverified. Explain the site details, records and access needed for approval. If the supplier refuses, pause approval of that route and consider another supplier.