Factory audits intimidate most buyers because they don't know what to look for. This checklist covers 47 specific things to verify — with explanations of why each matters. If you're earlier in the process, start with our complete sourcing guide before diving into audit specifics. If you need to verify a supplier's legitimacy before scheduling a visit — checking their business registration, cross-referencing certifications, and running online lookups — see how to verify a Chinese supplier first.

Why factory audits matter

Skipping a factory audit is one of the most expensive mistakes a hardware buyer can make. The cost of a proper audit runs $300–$800. The cost of not doing one can be orders of magnitude higher.

A UK consumer electronics seller ordered 3,000 units of a Bluetooth speaker from a supplier with strong Alibaba reviews and two years of Gold Supplier status. No factory audit was done. The shipment arrived eight weeks later: components didn't match the agreed BOM, FCC documentation referenced a different product model, and the packaging used a trademarked logo without authorization. Amazon rejected the entire shipment. The seller ate the cost of the goods, freight, duties, and destruction fees — approximately $28,000 in total losses, plus four months of lost sales velocity. The supplier had been a trading company reselling assembled goods from a subcontractor they'd never disclosed.

A one-day factory visit would have caught all three problems before a single dollar of production money was committed. For consumer electronics sourcing especially, where certification requirements are strict and Amazon compliance is unforgiving, auditing before production is non-negotiable.

Pre-audit preparation

Walking into a factory visit unprepared wastes both your time and theirs. Before you schedule the audit, assemble the following:

Your product specification package: A BOM (Bill of Materials) listing every component with part numbers, a mechanical drawing or CAD file if relevant, and the product specification sheet. This is what you'll use to verify the factory actually understands what they're making.

Certification requirements list: Write out every market certification your product needs — FCC for the US, CE for Europe, RoHS across both, TELEC for Japan, PSE for Japan's power products. Bring this list and check each one explicitly. Don't assume a factory understands your target market's requirements.

Your quality standards document: If you don't have one yet, use IPC-A-610 Class 2 as the baseline for commercial electronics. Write down your visual inspection criteria and packaging requirements before the visit.

A competitor product sample: If you can bring a competing product of the quality level you're targeting, use it as a reference during the visit. Show the factory your target and ask specifically how they'd achieve that standard.

Questions about capacity and clients: Before you arrive, prepare specific questions — not yes/no questions the factory can answer favorably, but open questions that require detail. "What's your current monthly production volume for Bluetooth audio products?" is better than "Can you make 5,000 units a month?" Ask for references in your product category. Ask how old their main SMT line is. Ask who currently manufactures similar products for them.

Section 1: Legal & Business (8 items)

1. Business license validity — Does the license cover manufacturing (制造业) or just trading?
2. License registration scope — Does the claimed product category match what's on the license?
3. Company age — How long have they been registered? Less than 2 years is a risk flag.
4. Bank account name — Does the bank account name match the company name on the license?
5. Export license — Do they have an export license, or do they use a freight forwarder's license?
6. ISO 9001 certification — Is it current? Which body issued it? Verify on the certification body's website. ISO 9001:2015 is the current quality management system standard — a factory certified to ISO 9001:2015 has had its QMS audited by an accredited third party.
7. Product certifications — FCC, CE, RoHS — are they actually held, or is the factory using a customer's certificate?
8. Trade assurance or equivalent — Do they participate in any third-party verification scheme?

Digging deeper on business legitimacy

The business license check (item 1) deserves more attention than most buyers give it. China's unified social credit system assigns every registered business an 18-digit social credit code starting with "9". Ask to photograph the physical license — a factory that won't show it in person has something to hide. Cross-check the code and registered business scope against the National Enterprise Credit Information System (SAMR) before placing a first order.

More importantly: does the license say 制造业 (manufacturing) or 批发零售业 (wholesale/retail)? Trading companies can and do present as manufacturers on Alibaba. This distinction matters because a trader has no control over the factory they're sourcing from, no ability to implement your QC requirements on the production line, and no accountability for subcontractor quality.

On Alibaba verification badges: "Gold Supplier" and "Verified Supplier" status are paid membership tiers, not quality certifications. They indicate the company has paid Alibaba's subscription and had a basic identity check — not that their products meet any technical standard. Cross-reference any factory's Alibaba profile against their 1688.com listing. If their 1688 profile shows them purchasing rather than selling the product you're discussing, they're a trader.

For export licenses (item 5): certain product categories — radio frequency equipment, batteries, specific electronic components — require specific export licenses beyond a general business license. If you're importing FCC/CE-certified products, the factory should have documentation showing they can legally export those goods.

Section 2: Facility (10 items)

1. Physical size vs. claimed capacity — A 200m² factory claiming 50,000 units/month output is lying.
2. Production line count — How many SMT lines? Manual assembly lines? Wave solder?
3. Worker count — Ask for payroll records. 20 workers making 10,000 units/month is physically possible or not?
4. Material storage — Is ESD-sensitive material stored properly? Is the storage area organized?
5. Work-in-progress storage — Is WIP labeled and tracked?
6. Finished goods storage — Is it separate from raw materials? Is it clean?
7. Power supply — Is there backup power? Electronics manufacturing needs stable power.
8. Cleanliness — Is the floor clean? Are tables organized? Dirty factories make dirty products.
9. Lighting — Is inspection lighting adequate? 1000+ lux for electronics assembly.
10. Temperature/humidity control — Required for component storage and SMT paste application.

Section 3: Equipment (9 items)

1. SMT line age — Equipment older than 15 years is a risk; older than 20 years is a red flag. This is especially relevant when auditing PCB assembly factories, where line age directly correlates with placement accuracy and defect rates.
2. Solder paste printer — Do they have an automatic printer, or are they hand-applying paste?
3. Reflow oven profile capability — Can they program and verify reflow profiles?
4. AOI (Automated Optical Inspection) — Do they have it? Is it in use or turned off?
5. X-ray capability — Required for BGA inspection. Do they have it in-house or outsource?
6. Wave solder — For through-hole components, is the wave solder properly maintained?
7. Hand soldering stations — Are they ESD-safe? Are iron tips replaced regularly?
8. ICT/FCT test fixtures — For your product specifically, do they have or will they build test fixtures?
9. Calibration records — Are test instruments calibrated? When was the last calibration?

What equipment age tells you

SMT equipment age (item 19) is a proxy for several things: the factory's investment in quality, their financial health, and their technical capability. A Yamaha or Juki pick-and-place machine from 2015 is meaningfully better than a domestic-brand machine from 2012 — the placement accuracy spec, feeder reliability, and software capability are all different.

Ask for the equipment list with purchase years. A factory manufacturing modern wireless products (BLE 5.0 chips with 0201 components) on a 15-year-old line is operating at the edge of that equipment's placement accuracy spec. It's not disqualifying, but it's something to understand before committing.

For your product specifically, ask whether they have or will build ICT/FCT (In-Circuit Test / Functional Circuit Test) fixtures (item 26). A factory that doesn't test 100% of units electronically before packing is relying on sampling — and sampling will miss latent defects that show up after the product ships.

Section 4: Quality Systems (11 items)

1. Incoming material inspection process — Do they inspect components when they arrive?
2. Incoming QC records — Can they show you actual records from the past month?
3. In-process QC — Who checks quality during production? How often?
4. Final inspection process — What's their sampling plan? AQL 2.5 or 4.0? If you need independent pre-shipment inspection, this is the stage where it slots in — before the balance payment is released.
5. Defect rate records — What's their reported defect rate? Is it credible?
6. Customer complaint handling — How do they track and respond to customer complaints?
7. Non-conforming material process — What happens to rejected components or products?
8. Engineering change control — How do they handle product changes? Do they notify customers?
9. IPC-A-610 knowledge — Do their QC inspectors know IPC-A-610? What class do they inspect to?
10. Golden sample practice — Do they use golden samples? Can they show you the current one?
11. Traceability — Can they trace a specific unit back to its production date and batch components?

Reading the quality system

The difference between a factory with real quality systems and one that's paper-compliant shows up in the details of items 28–38.

For IPC-A-610 (item 36): ask the QC manager which class they inspect to. Class 2 is the baseline for commercial electronics. Class 3 is for high-reliability applications (aerospace, medical). A factory that can't name the class they use doesn't actually know IPC-A-610 (the Acceptability of Electronic Assemblies standard) — they've put the poster on the wall without training to the standard.

For defect rate records (item 32): a credible outgoing defect rate for electronics assembly is 0.3%–1.5% for commercial products. If a factory reports 0% defects, they're either lying or not measuring. If they report 5%+, quality control is failing. Ask to see the actual tracking sheet — real factories have them in a binder or spreadsheet, updated by line supervisors.

For engineering change control (item 35): this matters more than most buyers realize. Ask what happens if they need to substitute a component due to a supply shortage. Do they notify the customer first? Do they require approval before substitution? A factory that doesn't have a formal change control process has probably already substituted components in orders without telling buyers. This is how "the same product" ships with different specs on the second and third order.

Section 5: Product-Specific (for electronics, 9 items)

1. ESD controls — Are wristbands in use? Are mat ground straps connected?
2. BT/WiFi module source — Where do they source the radio module? Grey market is a risk.
3. Battery source and documentation — UN38.3 test reports for lithium batteries.
4. Firmware flashing process — How is firmware loaded? Is the version controlled?
5. Product testing — What do they test on 100% of units before packing?
6. Waterproofing process — For IPX-rated products, how is sealing verified? Pressure test?
7. Cosmetic inspection criteria — Do they have a written standard, or is it subjective?
8. Packaging verification — Is drop testing done? Carton marking compliance checked?
9. Regulatory marking verification — Is CE/FCC marking correct and complete on production units?

Red flags that should stop an order

Some audit findings are conditionally remediable — you can require the factory to fix a specific issue before production begins and verify the correction. But certain findings mean you should walk away without placing the order.

Factory refuses to show the production floor. Any legitimate manufacturer will walk you through their facility. Reluctance to show you the production environment means either the facility doesn't match what they've claimed, or production for your product would be subcontracted without disclosure.

Claims certifications but can't produce original test reports. A factory that says "we have FCC certification" but can't provide the actual grant letter and test report with matching model numbers is using someone else's certification or misrepresenting their compliance status. This is a legal problem for the importer — not just a quality problem.

Price quote 30%+ below market average. Electronics manufacturing has fairly transparent cost structures. If a factory's quote is dramatically below every other supplier you've quoted, they're planning to hit the margin somewhere else — typically through component substitutions or cutting QC steps. The EU startup Bluetooth speaker case is a good example of how a suspiciously low quote led to specification problems at the shipment stage.

No dedicated QC department. In a factory of 50+ workers, QC should be a separate function from production, with at least one dedicated QC person who reports separately from the production manager. If the factory tells you "the production team handles quality," there's no independent check on production quality decisions.

Can't name any existing overseas clients in your category. Ask which foreign buyers they currently produce similar products for. They don't need to name them specifically — client confidentiality is reasonable — but they should be able to describe the product category, volume, and target market. A factory that can't describe any comparable client experience has likely never manufactured your type of product at scale.

ESD controls are non-functional. Walk the line and look at whether wristbands are actually worn and connected, whether mats are grounded, whether ESD-sensitive components are in appropriate packaging. Decorative ESD controls (wristbands hanging on hooks, mats with unplugged ground cords) mean ESD damage is an ongoing production problem.

Ownership or management changes in the past 12 months. This isn't always a red flag, but it warrants investigation. A factory that changed ownership recently may have also changed its key technical staff, quality systems, or component sourcing relationships — all of which can affect your product quality without being visible from the outside.

How to use this checklist

Don't present this as a questionnaire — factories will give you the answers they think you want to hear. Instead, ask open-ended questions and observe. "Show me your incoming inspection process" will tell you more than "Do you do incoming inspection?" (The answer to the second question is always yes.)

Disqualifying findings: items 1–4 (legal irregularities) and items 39–47 (ESD failures, undocumented firmware) should be treated as disqualifying without remediation. Everything else is conditionally remediable. In one case, a Japanese distributor saved 22% by switching factories after an audit revealed the original supplier was a trader, not a manufacturer.

Need someone to run this audit for you?

Our Factory Audit & Verification service covers this entire checklist — with on-site visits, photo documentation, and a written pass/conditional/fail report delivered within 48 hours.

Frequently asked questions

How long does a factory audit take?
A standard audit takes 4–8 hours on-site for an electronics factory. Add 1–2 days for travel if the factory is outside Shenzhen or Dongguan. We deliver the written report within 48 hours of the visit.

Can I do an audit remotely?
A partial audit is possible — you can verify business registration, request photos of the facility, and review certifications remotely. But equipment verification, ESD compliance, and quality process observation require physical presence. Remote-only audits miss the items that matter most.

How much does a factory audit cost?
Our standalone factory audit service is priced at $300–$800 depending on location and scope. Audit is included at no extra charge in our commission-based sourcing engagements.

What happens if the factory fails the audit?
We issue a Pass / Conditional / Fail rating. Conditional means specific remediation steps are required before production begins — we follow up to verify. Fail means we recommend finding an alternative factory; we'll restart the search at no additional cost if you're in a commission-based engagement.

Do you audit factories I found myself?
Yes. Audit is a standalone service. We can audit any factory in Shenzhen, Dongguan, Yiwu, and most other manufacturing regions in China.

Our factory audit service pricing explains how audit fees are structured — project-based or included in a monthly retainer.