Is a PI or PO Enough, or Do You Need a Formal Contract with a Chinese Supplier?

There is no document called “Manufacturing Agreement.” What you have instead is a quotation, a pro forma invoice, your purchase order, a month of email and WeChat messages, a bank transfer, and a message from the factory saying production has started.

Then a problem appears. The supplier says your PO terms were never accepted; you say the payment accepted the order. Both sides point to a different document.

The first question is whether that record already formed a contract; the second, and usually the more important, is what the contract actually says. A thin document chain may be enough to prove a sale while still leaving the buyer exposed on product acceptance, payment, tooling, intellectual property, and remedies.

Do not begin by asking whether a PI or PO is “legally binding” in the abstract. Reconstruct the transaction, identify which terms were actually accepted, and only then decide whether a short confirmation will close the gaps or a fuller contract review and negotiation is needed.

Contract formation and contract protection are different questions

A contract can exist without a document titled “Contract.” Under Articles 469 and 471 to 483 of the PRC Civil CodePRC Civil Code · Articles 469 and 471–483Contracts may be made in writing, orally, or in another form. Retrievable data messages can be written form, and a contract is generally formed through offer and acceptance.Official text · SPC ↗ , the parties may contract in written, oral, or other form, retrievable electronic communications can count as writing, and a contract is generally formed through offer and acceptance .

That means a PI, a PO, an email or WeChat exchange, a platform order, or any combination of them can establish a deal, and payment, production, shipment, and acceptance of the goods can reinforce that conclusion. Article 490PRC Civil Code · Article 490Where the parties use a written contract, it is normally formed on signature, chop, or fingerprint; accepted main performance can also form it before those formalities are completed.Official text · SPC ↗  also recognizes formation through accepted main performance even when a contemplated written contract has not yet been signed or chopped.

Existence, however, is a low threshold compared with protection: a record that proves “1,000 units at USD 8 each” may say nothing reliable about:

• which Chinese legal entity owes performance;
• the controlling specification and approved sample;
• objective inspection and acceptance criteria;
• whether the balance is due before or after inspection;
• ownership and permitted use of drawings, packaging, and tooling;
• subcontracting and change control;
• refund, repair, replacement, and damages; or
• governing law, forum, language, notices, and evidence.

A buyer can therefore have a valid contract and a weak case at the same time.

Reconstruct one transaction timeline

Start with the entire record, not the document that best supports your preferred answer, and put these items in date order:

1. quotations and product discussions;
2. the supplier’s PI and any revised PI;
3. your PO and incorporated standard terms;
4. specifications, drawings, samples, testing requirements, and packaging files;
5. email, WeChat, WhatsApp, and platform messages;
6. payment instructions and bank records;
7. production, inspection, shipping, and acceptance records; and
8. later changes to price, quantity, timing, or product requirements.

Preserve full conversations with account identity, timestamps, attachments, and the surrounding messages, because a cropped screenshot of “OK” does not show what was accepted. For practical evidence steps, see the guide to preserving WeChat evidence for a Chinese court.

Then build a term table: for each material issue, note what the quotation said, what the PI said, what the PO said, what later messages changed, and how the parties performed. Conflicts that are invisible when each document is read alone tend to surface immediately in this format.

Seven questions determine whether the record is usable

1. Who is the supplier?

Use the supplier’s complete registered Chinese name and Unified Social Credit Code, not only an English trading name, and compare the entity shown on the Chinese business licence, PI, PO acceptance, invoice, bank account, export documents, and company chop.

If a mainland factory performs while a Hong Kong company or an unrelated trading company receives payment, do not assume they are interchangeable. Identify which entity sells, which makes the goods, which receives payment, and which has accepted the obligations, because a demand against “the factory” becomes difficult when the record names only another company.

2. Was there a sufficiently definite offer?

The record should permit a decision-maker to identify the essential bargain. Product, quantity, price, currency, and the parties are the starting point; delivery timing, place, payment sequence, and specification may also be central, depending on the transaction.

A quotation marked “for discussion only,” an expired quote, or a PI that leaves product requirements open may be an invitation to negotiate rather than a final offer. Conversely, a detailed PI requesting a stated deposit by a deadline may look much more definite.

3. What counted as acceptance?

Acceptance may be a signed or chopped confirmation, a clear written reply, payment requested by the offer, or performance that the other party accepts; the answer depends on the wording and the conduct.

Silence should not be overread either: a supplier’s failure to object to your PO is not automatically acceptance of every term on the back. Look for affirmative conduct tied to that PO: an order confirmation, a deposit request, a production update referring to the PO number, or shipment against its specifications.

4. Did the reply change a material term?

A reply that changes price, payment, product, quantity, delivery, liability, or dispute resolution may be a counteroffer rather than an acceptance , which is why “battle of forms” problems arise when the buyer sends a PO with one set of terms and the supplier returns a PI with another.

Nor is a slogan such as “the last form wins” a safe guide: PRC law and the CISG both require a more careful examination of offer, acceptance, material changes, and later conduct. The practical solution is to identify the conflict and sign a final confirmation stating which documents control and in what order.

5. Did performance cure missing formalities?

It may. Payment accepted by the supplier, production started at the buyer’s instruction, or goods delivered and accepted can prove a contract despite a missing signature. But performance does not necessarily import every unacknowledged standard term.

The supplier may, for example, clearly accept the order’s product and price while disputing an arbitration clause hidden in a linked webpage, so analyze the formation of the sale separately from the incorporation of each disputed term.

6. Was the person authorized?

Messages from a sales employee can be relevant, but authority still matters, so record the employee’s company email, WeChat account, title, prior dealings, and whether the company implemented the employee’s instructions. For final execution, use the correct legal entity, an authorized signatory, and the agreed Chinese company chop.

An unofficial English stamp or a sales representative’s personal signature is not equivalent to verifying the counterparty and execution authority.

7. Does the contract impose a special effectiveness condition?

Some drafts say they become effective only when both parties sign, when the supplier applies a company chop, when a deposit arrives, or when a separate approval occurs. A court or tribunal will read that wording together with the parties’ later conduct and applicable law.

Nor should you assume that Article 490 overrides every expressly agreed condition: if the document says no contract exists until a named formality is complete, that wording deserves specific review before payment.

What a PI usually proves, and what it often leaves out

A pro forma invoice is usually a pre-shipment commercial document, one that may identify the seller, buyer, goods, quantity, price, payment account, Incoterm, and delivery estimate. Combined with acceptance and payment, it can be powerful evidence of the sale.

Its weaknesses are just as predictable. Many PIs use a shortened supplier name, a broad product description, “30/70” payment shorthand, an estimated lead time, and no workable remedy, and they often omit inspection standards, sample hierarchy, ownership of custom work, subcontracting controls, and dispute resolution.

So the correct conclusion is not that “a PI is never a contract”; it is that a PI may prove a contract while rarely being designed to allocate all manufacturing risk.

What a PO usually proves, and why sending one is not enough

A purchase order usually communicates the buyer’s order and internal controls, and it may attach detailed specifications and buyer-friendly standard terms. But sending the PO is only the first step, because the buyer must still prove that the supplier accepted those terms.

Common weaknesses include:

• the PO names an English trade name rather than the registered company;
• standard terms appear only through a broken or changeable web link;
• the supplier never signs or refers to the PO;
• the supplier’s PI contains conflicting payment, delivery, or forum terms;
• incorporated documents are not attached or versioned; and
• a later WeChat exchange informally changes the order.

Ask for an order confirmation that identifies the PO, attaches the final specification, accepts the document hierarchy, and is signed or chopped by the proper entity. A short confirmation of that kind can do more than another unacknowledged ten-page attachment.

Emails and WeChat can bind, but preserve the full context

The legal recognition of electronic records is not limited to contract formation. The PRC Electronic Signature Law recognizes data messages and addresses when electronic records satisfy the written and original-form requirements, and PRC evidence rules likewise treat instant messaging and communication-group information as electronic data .

That does not make every message conclusive, though. A decision-maker still asks who controlled the account, whether the record is complete and authentic, what the participants meant, and whether a later message superseded an earlier one, so preserve exports where available, the device and account information, attachments in their original format, payment references, and messages showing subsequent performance.

Plain language matters as well: “Noted,” “we will try,” and “should be okay” may not show final acceptance. Ask for direct confirmations instead:

Please confirm that [full Chinese legal name] accepts PO 1048, the attached Specification V3 dated 18 July 2026, and the payment, inspection, delivery, and dispute terms listed in the attached order confirmation.

Then insist on an unqualified acceptance rather than another vague response.

The CISG may govern even if your papers never mention it

For an international sale of goods, the United Nations Convention on Contracts for the International Sale of GoodsUnited Nations Commission on International Trade LawUnited Nations Convention on Contracts for the International Sale of Goods (Vienna, 1980) (CISG) | United Nations Commission on International Trade LawDate of adoption: 11 April 1980 Entry into force: 1 January 1988 Purpose The purpose of the CISG is to provide a modern, uniform and fair regime for contracts …uncitral.un.org↗ may apply when the parties have places of business in different Contracting States or when applicable conflict rules lead to a Contracting State’s law. Parties can exclude or modify its operation, but silence does not necessarily exclude it.

The CISG covers formation and the parties’ sale obligations, but it does not govern every issue: its Article 4 generally leaves contract validity and property effects outside its scope , and those questions may fall to the law selected by the contract or to conflict-of-laws rules.

China is a CISG Contracting State, and its current status entry lists a declaration concerning Article 1(1)(b), not a current Article 96 written-form reservation, so old templates that still say China always requires a written CISG contract should not be relied on. Even so, written evidence remains commercially essential, because the real problem is proving the agreed deal, not merely satisfying a form rule.

Standard terms require more than attachment

Buyer and supplier forms often contain standard terms. Under Articles 496 to 498 of the Civil CodePRC Civil Code · Articles 496–498A provider of standard terms must use fairness, call attention to significant terms, and explain them on request. Certain unfair exclusions or shifts may be invalid, ambiguity is read against the provider, and negotiated terms prevail.Official text · SPC ↗ , the provider of standard terms has duties of fairness, notice, and explanation for terms that materially affect the other party . Unreasonable exclusions, aggravated obligations, or the removal of major rights can be invalid, ambiguity is generally construed against the provider, and negotiated terms prevail over standard terms.

That is one more reason not to bury the clauses that matter: put payment triggers, product acceptance, liability, governing law, and forum where both sides can see and negotiate them, and preserve the redline or message showing that they were actually discussed.

Decide whether you need a confirmation, a review, or negotiation

Use the smallest document package that actually controls the risk.

A short order confirmation may be enough for a low-risk, repeat purchase of a standard product when the entity, specification, quantity, price, payment, delivery, acceptance, and dispute terms are already coherent.

A contract review is appropriate when documents already exist but you need to identify formation issues, conflicting terms, missing protections, and enforcement problems before payment.

Review plus a negotiation strategy is appropriate when the supplier has pushed back, the buyer needs ranked priorities, and each proposed concession should be matched with a protection or commercial adjustment.

Lawyer-led negotiation is appropriate when the transaction is valuable, custom assets or regulated goods are involved, the supplier is sophisticated, or the dispute clause and entity structure create meaningful enforcement risk.

A custom manufacturing arrangement usually needs a master agreement plus order-level documents. A practical package can include:

• a master supply or manufacturing agreement;
• a PO or order schedule with commercial terms;
• version-controlled specifications and approved-sample rules;
• inspection and acceptance procedures;
• tooling, IP, confidentiality, and subcontracting terms where relevant; and
• one document-hierarchy clause stating what controls in a conflict.

The purpose is not paperwork for its own sake; it is to make the same entity, product, payment sequence, and remedy visible before money and leverage move to the supplier.

Summary

If production has not started, consolidate the deal now. If a deposit has been paid, object promptly to conflicting terms and obtain a signed clarification before sending the balance. If the supplier has gone quiet after taking the deposit, switch from consolidating the paperwork to the recovery sequence in Chinese Supplier Went Silent After Your Deposit. If goods are already in production, take care that your wording does not accidentally cancel an existing contract while you are trying to improve it.

The most useful contract review does not stop at “is this binding?” It identifies what is likely binding, what remains disputed, what evidence is missing, and which changes must be negotiated before the buyer takes on more risk.

PI, PO, email, and WeChat records can form a real contract with a Chinese supplier, but they can just as easily form a fragmented contract that proves the order while leaving the most expensive questions unanswered. Reconstruct the accepted deal, resolve the conflicts in one final record, and match the document depth to the transaction’s actual exposure. For a structured starting point on that final record, the free bilingual China supplier contract template covers the terms a PI and PO chain usually leaves open.

For help choosing the right level of support, Kelly Zhang Law provides contract review, contract review with a negotiation strategy, and lawyer-led contract negotiation for China supplier transactions. Contact Kelly Zhang Law with the current document chain before the next payment, production approval, or tooling commitment.

References

1. PRC Civil Code, Articles 469, 471–483, 490, and 496–498, official SPC textwww.court.gov.cn中华人民共和国民法典 - 中华人民共和国最高人民法院最高人民法院政务网站,最高人民法院网，最高人民法院，最高人民法院网是人民群众了解和联系最高人民法院的重要窗口，承载着司法公开、法治宣传、服务群众、接受监督等重要使命。是最高人民法院的政务网站，是最高人民法院在互联网上唯一的正式身份。www.court.gov.cn↗.

2. PRC Electronic Signature Law, including rules on data messages and electronic records, official MOFCOM text中华人民共和国商务部中华人民共和国电子签名法商务部发布的《电子签名法》官方文本，含数据电文与电子记录相关规则。dcj.mofcom.gov.cn↗.

3. Supreme People’s Court Provisions on Evidence in Civil Litigation, Article 14 electronic-data categories, official SPC textwww.court.gov.cn最高人民法院关于民事诉讼证据的若干规定 - 中华人民共和国最高人民法院最高人民法院政务网站,最高人民法院网，最高人民法院，最高人民法院网是人民群众了解和联系最高人民法院的重要窗口，承载着司法公开、法治宣传、服务群众、接受监督等重要使命。是最高人民法院的政务网站，是最高人民法院在互联网上唯一的正式身份。www.court.gov.cn↗.

4. UNCITRAL, CISG text and explanatory materialsUnited Nations Commission on International Trade LawUnited Nations Convention on Contracts for the International Sale of Goods (Vienna, 1980) (CISG) | United Nations Commission on International Trade LawDate of adoption: 11 April 1980 Entry into force: 1 January 1988 Purpose The purpose of the CISG is to provide a modern, uniform and fair regime for contracts …uncitral.un.org↗ and current status tableUnited Nations Commission on International Trade LawStatus: United Nations Convention on Contracts for the International Sale of Goods (Vienna, 1980) (CISG) | United Nations Commission on International Trade LawAuthoritative information on the status of the treaties deposited with the Secretary-General of the United Nations, including historical status information, ma…uncitral.un.org↗.