← Buyer GuidesHow to Verify a Chinese Factory: Audit Checklist
A factory audit is an on-site assessment of a manufacturer's capability, quality system, and export readiness — the due-diligence step that separates real factories from trading companies.
Key points
- Desktop audit first (licenses, certificates, export records), on-site audit second. Never skip straight to price.
- Walk the full flow: raw material warehouse → injection molding → assembly → QC lab → finished-goods warehouse.
- Ask what is outsourced. Core processes done in-house (molding, membrane handling) mean better control.
- Check the QC lab: calibrated TDS meters, pressure test rigs, and written inspection records — not just equipment on display.
- Red flags: no QC lab, no export records, refusal of unannounced visits, prices far below market.
Action checklist
- Collect business license, export license, and ISO 9001 certificate (verify dates).
- Confirm production lines match your product (RO assembly, not just filter cartridges).
- Photograph the QC lab: TDS meters, hydrostatic test rig, incoming-material area.
- Review 3 recent inspection reports — look for real defect records, not blank passes.
- Ask for the outsourcing list: which processes leave the building?
- Check finished-goods warehouse: FIFO labeling, humidity control, packing standards.
- End with a written corrective-action list and a deadline, not a handshake.
Common questions
How much does a third-party factory audit cost?
Typically a few hundred USD per man-day plus travel, depending on the city. Compared to a bad container, it is the cheapest insurance you will ever buy.
Can I audit by video call instead?
For re-audits of known suppliers, yes. For a first-time supplier, an on-site visit (by you or an agent) catches things video calls miss — warehouse conditions, actual staffing, and whether the QC lab is really used.
Related reading
A note on honesty. CWS provides sourcing and QC services for water purification products. This guide is general information for overseas buyers — not a guarantee of any outcome. We don't promise the lowest price in China, and we don't promise zero defects. What we do promise: written inspection criteria, lot traceability, and telling you when something is outside what we can verify.