How to choose a factory in China

Choosing a factory is one of the biggest decisions in a hardware project. The right partner catches design problems early, keeps quality steady and tells you bad news quickly. The wrong one can cost months.

There's no perfect checklist that guarantees a good result, and no directory (including this one) can vouch for a supplier. What you can do is reduce risk step by step. This guide shows how.

Step 1: know exactly what you're buying

Before searching, write down:

The process you need: CNC machining, injection molding, PCB assembly, die casting, full product assembly, or several of these.
The quantity: 50 prototypes and 50,000 production units need very different partners.
Your stage: prototype, pilot or mass production. See EVT, DVT, PVT explained.
What matters most: price, speed, precision, cosmetic quality, English communication, or engineering help.

A factory that is excellent at millions of simple parts may be a poor fit for 200 complex ones, and the reverse is also true. Fit matters more than size.

Step 2: understand who you're talking to

Suppliers in China come in a few types, and they often look similar online:

Factories: own the machines and make the parts. Usually best for price and technical conversation, once you're at volume.
Trading companies: sell parts made by other factories. They may offer easier communication and a wider range, but add a margin and a layer between you and production. Some are open about this; some present themselves as factories.
Sourcing agents: work on your behalf to find and manage suppliers, usually for a fee or commission. Useful if you can't be on the ground.
Contract manufacturers (CMs) / EMS: build and assemble your whole product, often managing sub-suppliers for plastics, metal and electronics.

None of these is "good" or "bad"; they suit different needs. What matters is knowing which one you're dealing with. Ask directly: "Do you make this in your own facility? Which processes do you do in-house and which do you outsource?"

Step 3: build a longlist

Common starting points:

Directories like this one, filtered by process and location (browse factories).
Online B2B platforms, where many suppliers list services.
Instant-quote platforms for prototypes, which give you a baseline price.
Referrals from other hardware founders, accelerators and meetups.
Trade fairs and visits to industrial areas in Shenzhen and Dongguan.

Aim for five to ten names. Look for evidence they do your process and your type of part: photos of similar work, an equipment list, and relevant industries.

Step 4: send a clear RFQ

Send the same package to everyone: files, quantities, material, finish, quality needs and delivery terms. See How to write an RFQ. How suppliers respond is itself useful information:

Did they reply within a reasonable time?
Did they ask sensible questions, or just send a number?
Did they give DFM feedback (suggestions to make it easier to manufacture)?
Is the quote broken down clearly?

Step 5: check what you can

You can't know everything from a distance, but you can check a lot:

Business licence (营业执照, yíng yè zhí zhào). Ask for a copy. Check that the company name matches the one on your contract and bank details, and that the registered business scope covers manufacturing, not just trading.
Bank details. The receiving account should normally be in the name of the company you're contracting with. Be very cautious if a supplier asks you to pay a personal account or a different company, or suddenly changes bank details by email.
Video call tour. Ask to see the production floor, the machines for your process, and the inspection area. It's quick and free.
Samples of similar work. Ask for photos or physical samples of parts like yours.
References. Ask if you can speak with an existing customer.
Certifications such as ISO 9001 (a quality management standard) if your industry needs them. Ask for the certificate and check it with the issuing body where possible.
A factory audit (验厂, yàn chǎng). For bigger commitments, you or a third-party inspection company can visit and assess the site. See Quality inspection explained.

A small group reviewing parts on a factory floor with a production manager during a factory visit

Step 6: compare quotes properly

Put the quotes side by side in a spreadsheet: tooling cost, unit price at each quantity, lead time, MOQ (起订量), payment terms, what's included, and who owns the tooling.

Be careful with a quote that is far below the others. It may be a genuine advantage, or it may mean a different material, skipped finishing, or a price that rises later. Ask why.

Step 7: start small

Don't jump straight to a large order:

Order samples (打样, dǎ yàng) or a small first batch.
Inspect them carefully against your drawing.
Sign a golden sample (金样) as the reference for production.
Run a pilot (试产) before mass production.

This costs a little time and money, and it's the most reliable way to learn how a supplier actually works.

Step 8: put key terms in writing

Before production, agree in writing:

Price, quantity, specs and drawing revision
Payment terms (a deposit, 定金, then balance, is common)
Lead time and what happens if it slips
Quality standard and inspection method
Tooling ownership
Confidentiality and IP protection (see NNN agreements explained)

Warning signs

Pressure to pay quickly, or to pay a personal or unrelated account
Unwillingness to do a video call or show the production floor
No questions at all about a complex part
Prices far below every other quote with no clear reason
Vague answers about which processes are in-house

One warning sign isn't proof of a problem, but it's a reason to slow down and ask more.

Keep reading

Next steps

Read the contract manufacturing hub
Browse factories and sourcing agents in the directory
See the Production stage of the Path
Glossary: 验厂 factory audit, 打样 sampling, 试产 pilot production
Not sure where to start? Get an intro

Updated 29 September 2026