CISG Contract Formation with Turkish Parties: When Is a Sales Contract Binding?

Under the CISG, a contract for the international sale of goods with a Turkish company can be formed without a signed written document, once a sufficiently definite offer is met by an acceptance. Foreign parties should identify the exact moment of formation before assuming no contract exists.

Contract formation determines whether, and from when, a sale is legally binding. Many foreign companies dealing with Turkish suppliers or buyers assume that without a signed contract there is no obligation. Under the CISG, which governs most international sales of goods between parties in different contracting states, formation can occur informally through correspondence, purchase orders, order confirmations or even conduct.

The CISG applies automatically to contracts for the sale of goods between parties whose places of business are in different states, at least one of which is a CISG contracting state, unless the parties have validly excluded it. Türkiye is a contracting state. Where the CISG's rules on formation do not resolve an issue, Turkish domestic law, principally the Turkish Code of Obligations No. 6098 and, for parties who qualify as merchants, the Turkish Commercial Code No. 6102, may become relevant as background law for matters the CISG leaves open.

Turkish courts and arbitral tribunals seated in Türkiye generally apply the CISG's own formation rules to international sales rather than domestic contract-formation doctrine, once the CISG's scope of application is established. Practice confirms that an offer must be sufficiently definite, indicating goods, quantity and price or a means of determining them, and that an acceptance can be an express statement or conduct indicating assent, such as dispatching goods or paying the price.

A recurring debate concerns silence: under the CISG, silence or inactivity does not by itself amount to acceptance. Another debate concerns partial or conditional acceptances that materially alter the offer's terms, which are treated as a rejection combined with a counter-offer rather than an acceptance. Determining whether an alteration is material is a fact-specific and sometimes contested exercise.

For the CISG's formation rules to apply, both the offer and any dispute about formation must fall within the CISG's substantive scope, meaning a sale of goods between parties with places of business in different states, at least one a contracting state, and no valid exclusion of the CISG. Communications should be reviewed for definiteness, timing of dispatch and receipt, and any conduct suggesting performance had begun.

An offer can be withdrawn before or at the same time it reaches the offeree, and it can often be revoked before acceptance is dispatched unless it states it is irrevocable or the offeree reasonably relied on it as irrevocable. Acceptance must generally reach the offeror within the time fixed or, if none is fixed, within a reasonable time given the circumstances. Late acceptance can still bind the offeror if it promptly treats it as effective.

Disputes over whether and when a contract was formed are decided by the court or arbitral tribunal with jurisdiction under the parties' agreement or applicable jurisdiction rules. Turkish commercial courts frequently hear such disputes when the Turkish party is sued or sues locally, and CISG formation issues are treated as substantive law questions decided on the merits.

Evidence should include the full chain of correspondence, purchase orders, order confirmations, invoices, delivery documents, prior dealings and trade usages between the parties, and any internal records showing when goods were dispatched or received. Because CISG formation can occur informally, the absence of a signed contract is not, by itself, evidence that no agreement exists.

A common mistake is assuming that a purchase order alone, without any response, creates a binding contract. Another is ignoring that a supplier's order confirmation with additional terms may constitute a counter-offer rather than an acceptance. Foreign companies also sometimes overlook that conduct, such as shipping or accepting goods, can itself form or confirm a contract even without further paperwork.

Does a contract need to be in writing to be enforceable against a Turkish party under the CISG? No. The CISG generally does not require a particular form, and a contract can be proven by any means, including witnesses and correspondence.

Can silence to an order confirmation count as acceptance? Generally no. Silence or inactivity alone does not constitute acceptance under the CISG.

What happens if a Turkish supplier's confirmation adds new terms? If the added terms materially alter the offer, the confirmation is treated as a counter-offer, and no contract is formed until the other party accepts those new terms.

Can the parties still choose to exclude the CISG's formation rules? Yes, subject to conditions, parties may exclude or vary the CISG, including its formation rules, through a clear contractual provision.

We regularly review commercial correspondence with Turkish counterparties to determine, as an initial and often decisive question, whether and when a binding contract came into existence before advising on breach, non-conformity or termination. Getting this threshold question right materially affects the strength of any later claim.