What a factory audit is for

A factory audit is the step between a supplier who sounds right on email and a purchase order you can defend. Its purpose is not to confirm the factory exists — it is to confirm that this specific facility already makes your kind of product, at your kind of volume, to the quality level you wrote down, and that the legal entity you pay is the one doing the work. An audit costs a fraction of one bad production run, which is why skipping it is the most expensive form of thrift in overseas manufacturing.

Step one: verify who you are actually dealing with

Before quality comes identity. Many "factories" that quote US founders are trading companies with a showroom and a network of subcontractors. Trading companies are not automatically bad, but you must know which one you have, because it changes pricing, control, and accountability — see factory vs trading company.

Ask for and check:

  • The business license, with the registered entity name and unified social credit code. Confirm the registered scope of business includes manufacturing, not only trade.
  • Name matching. The entity on the license, the quotation, the contract, and the bank account should be the same. A mismatch between contract party and payee is a classic loss scenario.
  • Export capability — whether they export directly or through an agent, and who appears on your customs documents as shipper.
  • Certificates, independently verified. ISO 9001 or ISO 13485 certificates should be checked on the issuing registrar's public database, not accepted as a PDF. Scope and expiry matter as much as existence.
  • Customer references in your product category, ideally US or EU brands, and a real conversation with at least one.

What to inspect on the production floor

The core question is fit between your product and what this plant genuinely knows how to do. A large, clean hall proves nothing if the machines in it are wrong for your process.

  • Equipment. What machines exist, in what sizes and tonnages, how old, and how many are running versus idle. Match the list to your process — see how to evaluate a contract manufacturer.
  • Subcontracting. Which operations leave the building — plating, painting, printing, heat treat, PCB assembly. Every outsourced step is a supplier you have not audited.
  • Capacity. Shifts per day, line utilization, and where your order sits in the mix. Being far too small a customer is as risky as being too large.
  • Incoming material control. Is there receiving inspection for resins, metals, and components, and what happens to rejected material? Ask to see nonconforming material quarantined and labeled.
  • Metrology. Calipers, gauges, CMM or vision systems, and current calibration records. No calibration records means no defensible dimensional data.
  • Process control. Work instructions at each station, first-article approval, in-process checks, and traceability records that connect a finished lot to its materials.
  • Tooling management. Where molds and fixtures are stored, how maintenance is logged, and who is recorded as owner — a topic worth reading in full: who owns your mold in China.
  • Component authenticity. For electronics, ask about approved vendor lists and how they handle brokered parts, because gray-market supply is a real hazard — see counterfeit electronic components.
  • Order and safety. Housekeeping, marked walkways, guarded machines, and reasonable working conditions correlate strongly with process discipline.
  • Relevant experience. Products like yours physically coming off a line — not a claim that they can make anything.

The trap most first-time importers fall into

Many suppliers operate multiple sites, and the polished hall shown to visitors is not always where your parts will be made. Ask explicitly: which building, which line, which shift will run my order? Then ask to see that line.

US-specific diligence that an ordinary audit misses

American importers carry obligations no Chinese supplier will raise for you:

  • Supply chain provenance. US law restricts imports linked to forced labor, and enforcement traces upstream inputs. You need documented visibility into raw material origin, not just final assembly.
  • Classification and duty exposure. Confirm the product's HTS classification and country of origin rules before you commit to a price — landed cost is the only number that matters, as covered in import duties and tariffs from China.
  • Regulatory marks. If your product needs certification marks, verify the factory understands that marks apply to your specific model and cannot be borrowed from a similar unit they built for someone else.
  • Contract protections. Put confidentiality, non-use, and non-circumvention terms in place before files are shared — see NNN agreements for China manufacturing.

Audit formats and what they cost

  • Desktop verification — license, certificates, references. Costs nothing but your time and should always happen first.
  • Live video walkthrough — you direct the camera in real time, unannounced enough that a staged tour is hard. Weak on documents, useful on reality.
  • Third-party on-site audit — an inspection firm sends an auditor with a standard checklist and returns a photographed report. Usually a few hundred to low four figures in USD, the best value in the whole process.
  • Your own visit or your engineering partner's — the most informative, and the right choice when tooling and a long-term relationship are at stake.

An audit qualifies the supplier; it does not guarantee the goods. Pair it with pre-shipment sampling — see AQL inspection explained — and set realistic first-order quantities using minimum order quantity negotiation.

Red flags that justify walking away

  • Refusal to show the production line, or to name the entity that will invoice you.
  • A quote far below every other bid, with no explanation of how.
  • Pressure to pay a large deposit to a personal or third-country account.
  • No engineering questions about your drawings — a real manufacturer always has some.
  • Willingness to copy or "improve on" another brand's product.
  • Certificates that cannot be verified with the issuing body.

We qualify suppliers before your money moves

Projects House manages overseas manufacturing for US clients: supplier shortlisting, audit specification, drawing packages the factory cannot misread, and inspection tied to payment. If you have a supplier you are close to committing to, send us the details through our contact form and we will tell you what still needs checking.