Oral Commercial Agreement With a Turkish Company: Can It Be Enforced in Court? 2026 Updated Guide

Can a foreign company enforce an oral commercial agreement against a Turkish company? Learn about contract validity, proof, WhatsApp messages, emails, invoices, witnesses, payments and commercial litigation in Turkey.

Foreign companies doing business in Turkey sometimes enter commercial relationships without signing a detailed written contract. The parties may negotiate by telephone, agree on essential terms during meetings, exchange WhatsApp messages or emails, issue invoices and begin performing their obligations without ever executing a formal agreement. A dispute may arise months later when the Turkish company denies the agreement, refuses payment, disputes the price or claims that particular contractual terms were never accepted. An oral commercial agreement is not automatically unenforceable merely because it was not reduced to a signed contract. However, validity and proof are separate questions. Certain transactions are subject to mandatory form requirements, and even where an oral agreement can legally exist, proving its precise terms in commercial litigation may become the central difficulty.

Are Oral Commercial Agreements Valid in Turkey?

As a general principle, Turkish contract law recognizes freedom of form unless legislation requires a particular form for the transaction concerned. This means that many ordinary commercial contracts can potentially be concluded orally or through conduct demonstrating mutual agreement.

The absence of a signed document therefore does not automatically mean that no contract exists.

Validity and Proof Must Be Distinguished

This distinction is essential.

A contract may be legally capable of being concluded orally, but the party seeking enforcement may still encounter evidentiary restrictions when attempting to prove the agreement and its terms before a Turkish court.

The first question is therefore whether the transaction required a particular legal form. The second is how the alleged agreement can be proved.

Some Commercial Transactions Require a Specific Form

Foreign companies should not assume that every transaction can be concluded orally. Turkish legislation imposes formal requirements for various transactions.

Where mandatory form is required for validity, an oral understanding may not produce the same legal consequences as a properly executed transaction.

The specific contract type should therefore be identified before assessing enforceability.

How Is an Oral Agreement Formed?

An enforceable contractual relationship generally requires corresponding expressions of intent concerning the transaction.

In a commercial dispute, the court may examine whether the parties actually reached agreement on essential matters such as the goods or services, price or pricing mechanism, quantity, performance obligations and other material terms.

Performance Can Be Powerful Evidence

The parties’ subsequent conduct may provide significant evidence of the existence of a commercial relationship.

For example, a foreign supplier may deliver goods, the Turkish company may accept them, invoices may be issued, partial payments may be made and additional orders may follow.

Such conduct can make a simple denial that “there was never any agreement” considerably more difficult to maintain.

Emails Can Become Critical Evidence

Business emails may show negotiations, acceptance of prices, quantities, delivery schedules, payment promises, complaints or acknowledgement of debt.

Foreign companies should preserve the complete email chain rather than individual screenshots.

WhatsApp Messages May Be Important

Commercial negotiations increasingly occur through WhatsApp and similar messaging applications.

Messages may potentially help establish what the parties discussed, who accepted particular conditions and whether the Turkish company subsequently acknowledged its obligations.

The evidentiary value of electronic communications depends on the circumstances, authenticity and applicable procedural rules.

Preserve the Entire Conversation

A party should avoid relying solely on isolated messages favorable to its position.

Preserve the complete conversation, including dates, participants, attachments and surrounding messages. Context can become important when the opposing party alleges that a screenshot was altered or taken out of context.

Invoices Are Important but May Not Prove Every Contractual Term

Invoices can provide significant evidence concerning the commercial relationship, goods, services and price.

However, an invoice should not automatically be treated as conclusive proof of every disputed contractual term.

The complete commercial record should be evaluated.

Commercial Books Can Become Relevant

Accounting and commercial records can play an important role in disputes between businesses.

Invoices recorded in company books, payment entries, account statements and other commercial records may help reconstruct the relationship between the parties.

Bank Transfers Can Support the Claim

A payment from the Turkish company can be particularly useful where the company later denies the underlying relationship.

Preserve bank records showing the amount, sender, recipient, date and payment description.

Partial Payment Can Be Significant

Suppose a Turkish company orally agrees to purchase machinery from a foreign supplier, accepts delivery and pays 30% of the invoice but refuses the remainder.

The partial payment can become an important part of the evidentiary picture when the buyer later alleges that no binding commercial agreement existed.

Purchase Orders Should Be Preserved

A purchase order may establish product, quantity, price, delivery conditions and other essential details.

Even where no master agreement exists, purchase orders combined with invoices, delivery documents and correspondence can help establish individual transactions.

Delivery Documents Can Be Crucial

Preserve delivery notes, transportation documents, customs documentation, warehouse records and signed receipt documents.

The foreign company should be able to demonstrate not only that negotiations occurred but also what performance was actually provided.

What If Services Were Provided Instead of Goods?

Service disputes can be more difficult because there may be no physical delivery.

Preserve reports, presentations, project files, meeting records, timesheets, correspondence, access logs and documents showing that the Turkish company received and used the services.

Can Witnesses Prove an Oral Commercial Agreement?

Witness evidence may become relevant in appropriate circumstances, but Turkish procedural rules concerning proof by document and witness evidence must be considered carefully.

A company should not assume that bringing an employee who attended the meeting will automatically be sufficient to prove a high-value commercial claim.

Written Evidence Is Particularly Important in High-Value Disputes

The larger the claim, the more important it becomes to construct the case around reliable documentary and electronic evidence.

Emails, messages, invoices, bank transfers, commercial books and performance records should be collected before litigation begins.

What If the Turkish Company Denies the Price?

Price disputes are common in oral-contract cases.

The foreign company should search for quotations, price lists, purchase orders, emails, messages, previous transactions, invoices and payment records demonstrating how the price was determined.

What If the Buyer Says the Price Was Renegotiated?

Review communications after the original agreement.

A buyer may argue that the parties later agreed to a discount or different payment arrangement. The chronology of communications becomes particularly important.

What If the Payment Date Was Never Written Down?

The absence of a written payment date does not necessarily eliminate the underlying claim. The applicable contractual rules, invoices, commercial practice and parties’ conduct should be examined to determine when payment became due.

What If There Was No Agreement on Currency?

Currency can become a major issue in international transactions.

The court may examine invoices, quotations, previous transactions, payment records and correspondence to determine what the parties actually agreed.

What If the Turkish Company Claims the Employee Had No Authority?

This can become a separate dispute.

The foreign company should determine who negotiated the transaction, that person’s position, previous dealings and whether the Turkish company acted in a manner indicating that the representative had authority.

Company Representatives Should Be Identified

Preserve email signatures, business cards, corporate correspondence and other records identifying the individuals involved.

A company may have difficulty denying its representative’s involvement after accepting the benefits of the transaction, although authority must always be analyzed according to the specific facts and applicable law.

Previous Transactions Can Help Explain the Relationship

If the parties conducted business repeatedly using the same informal process, previous transactions may help establish their commercial practice.

For example, repeated orders may historically have been made through WhatsApp, followed by delivery, invoicing and payment without formal contracts.

That history can become relevant to understanding the disputed transaction.

Do Not Fabricate a Contract After the Dispute Begins

A foreign company should never create a document and present it as though it had been signed earlier.

The proper approach is to reconstruct the actual commercial relationship using genuine contemporaneous evidence.

Preserve Original Electronic Evidence

Do not rely only on printed copies.

Preserve original emails, electronic files, message histories and available metadata. Authenticity can become important if the Turkish company disputes the communications.

What If the Turkish Company Admits the Debt in a Message?

A message acknowledging that payment is due can be highly important evidence.

The precise wording and context should nevertheless be examined carefully to determine what exactly was acknowledged.

What If the Company Says, “We Will Pay Next Month”?

Such a statement may support the creditor’s position, particularly when connected with an identifiable invoice or transaction.

Preserve the complete conversation.

What If the Turkish Company Objects to the Invoice?

The timing and content of the objection should be examined carefully.

Determine whether the buyer disputed the goods, quantity, price, quality or merely requested additional time for payment.

These are materially different positions.

Acceptance of Goods Can Affect the Dispute

If goods were delivered and used without immediate rejection, the buyer’s subsequent conduct may become important.

The seller should preserve evidence of delivery, acceptance and any complaints received.

Defective Goods Allegations Must Be Taken Seriously

The Turkish buyer may admit the transaction but refuse payment by alleging defects.

The dispute then changes from “Was there a contract?” to questions concerning conformity, inspection, notification of defects and contractual remedies.

Foreign Companies Should Preserve Quality Evidence

Keep inspection certificates, photographs, technical specifications, manufacturing records and communications concerning acceptance.

This can become important if non-payment is defended through alleged defects.

Can an Oral Contract Be Terminated?

Potentially, but the legal consequences depend on the contract type, agreed terms and applicable statutory rules.

Where the existence of the agreement itself is disputed, termination communications should be preserved carefully.

Notice Communications Can Become Evidence

A termination notice, payment demand or response may contain admissions concerning the underlying relationship.

For example, a Turkish company that responds, “We terminated because delivery was late,” may be taking a position inconsistent with a later claim that no contract ever existed.

Mediation May Be Required Before Commercial Litigation

Depending on the nature of the commercial claim and applicable procedural rules, mandatory mediation may need to be completed before filing certain commercial lawsuits in Turkey.

The specific claim should be assessed before proceedings are initiated.

A Strong Mediation File Is Important

Mediation should not be treated merely as a procedural formality.

The foreign company should prepare its invoices, payment records, communications and calculation of the claim before negotiations begin.

Can the Foreign Company Start Enforcement Proceedings?

Depending on the nature of the receivable and available evidence, enforcement proceedings may be considered.

If the debtor objects, further litigation may become necessary to establish or enforce the claim.

Jurisdiction Must Be Determined

International commercial disputes can raise questions concerning which Turkish court has jurisdiction and whether the parties agreed on a particular forum.

Emails, purchase orders and standard terms should be checked for jurisdiction clauses.

Applicable Law Must Also Be Examined

The fact that one party is Turkish does not automatically resolve every choice-of-law question in an international commercial relationship.

The governing law should be determined before building the substantive claim.

Arbitration Clauses Can Create Separate Issues

Sometimes parties never sign a master contract but exchange standard terms containing an arbitration clause.

Whether an arbitration agreement was validly concluded requires separate analysis because arbitration agreements are subject to specific formal requirements.

Standard Terms Should Be Collected

Search quotations, purchase orders, order confirmations, invoices, websites and correspondence for references to general terms and conditions.

The question is not merely whether the terms existed, but whether they became part of the contractual relationship.

Limitation Periods Should Be Checked Immediately

A foreign company should not postpone enforcement merely because negotiations continue.

The applicable limitation period depends on the nature of the claim and contractual relationship.

Send a Structured Payment Demand

Before litigation, the foreign company should consider sending a formal demand clearly identifying the transaction, invoices, outstanding amount and payment request.

The debtor’s response may also become relevant evidence.

Avoid Emotional Correspondence

Once a dispute develops, communications should remain factual.

Do not make threats or unsupported accusations. Assume that every email and message may later be submitted to a court.

Build a Chronological Evidence File

A practical litigation file should begin with the first negotiation and continue through performance and non-payment.

The chronology may include quotation, acceptance, purchase order, delivery, invoice, partial payment, complaints, payment promises, formal demand and subsequent correspondence.

Quantify the Claim Correctly

Determine principal debt, currency, due dates, contractual interest if applicable and other legally recoverable amounts.

Do not inflate the claim with unsupported losses.

Lost Profit Claims Require Strong Evidence

If breach of the oral agreement allegedly caused additional commercial losses, causation and amount should be documented separately.

A claim for the unpaid invoice is generally evidentially different from a claim for substantial future profits.

Foreign Companies Should Secure Evidence Before Relationships Deteriorate Further

Once litigation becomes likely, employees may leave companies, email accounts may be closed and message histories may disappear.

Preserve relevant evidence immediately.

2026 Practical Litigation Strategy

A foreign company seeking to enforce an oral commercial agreement against a Turkish company should first identify the contract type and determine whether any mandatory form requirement applies. It should then reconstruct the transaction using contemporaneous evidence: emails, WhatsApp communications, purchase orders, invoices, delivery documents, bank transfers, accounting records and admissions.

The legal strategy should distinguish existence of the contract, exact contractual terms, performance by the foreign company, breach by the Turkish company and the amount of the resulting claim.

Frequently Asked Questions

Is an oral commercial agreement automatically invalid in Turkey?

No. Many contracts can potentially be concluded without a formal written agreement unless legislation imposes a particular form requirement.

Can WhatsApp messages prove the agreement?

They can potentially constitute important evidence depending on their content, authenticity and applicable procedural rules.

Are invoices enough to prove the entire contract?

Not necessarily. They can be important evidence, but the complete commercial relationship should be examined.

Can bank transfers prove the agreement?

Payment records can strongly support the existence and performance of a commercial relationship, particularly when connected with identifiable invoices or orders.

Can witnesses prove an oral agreement?

Witness evidence may be relevant, but procedural restrictions concerning proof should be examined. Documentary and electronic evidence remains particularly important.

What if the Turkish company accepted the goods but never signed anything?

Acceptance, use, invoicing, correspondence and payments may all become relevant in proving the contractual relationship and performance.

What if the Turkish company denies the agreed price?

Quotations, purchase orders, messages, previous transactions, invoices and partial payments should be examined.

Can a foreign company sue in Turkey?

Potentially, yes. Jurisdiction, governing law, contractual dispute-resolution clauses and mandatory procedural steps should first be analyzed.

Is mediation required before filing the lawsuit?

Certain commercial monetary claims may be subject to mandatory mediation before litigation. The specific dispute should be reviewed before filing.

What should the foreign company do first?

Preserve every piece of contemporaneous evidence and reconstruct the transaction chronologically. In an oral-contract dispute, the strongest case is usually built not around one document but around a consistent chain of negotiations, performance, delivery, invoicing, payment and subsequent acknowledgements.

Client-Focused Legal Support for Oral Commercial Contract Disputes in Turkey

Disputes involving oral commercial agreements can require detailed analysis of contract formation, electronic correspondence, invoices, commercial books, bank transfers, delivery records, authority of company representatives, unpaid receivables and international jurisdiction. Fırat Fesih Kaya Law Office assists foreign companies, international suppliers, investors and exporters in commercial disputes with Turkish companies. Lawyer Fırat Fesih Kaya provides legal assistance in evaluating contractual evidence, preparing payment and receivables claims, conducting mandatory mediation where applicable, initiating commercial litigation and enforcement proceedings, and defending foreign companies against contractual counterclaims.

Phone:
+90 312 434 22 22

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+90 532 769 22 22

Email:
info@firatfesihkaya.av.tr

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Mevlana Boulevard No:221, Yıldırım Tower, Office No:148, 06520 Balgat, Çankaya, Ankara, Turkey