Contract Law
This section covers the core institutions of the law of obligations — from contract formation to termination, from performance to adaptation. The articles are prepared in light of the Turkish Code of Obligations (No. 6098).
Standard Terms and Consumer Protection: The 'Unwritten' Sanction
Review of unfair terms under TBK m.20-25 and TKHK m.5
When are standard contractual clauses invalid? Standard terms, the 'unwritten' sanction and review of unfair terms in consumer contracts.
Standard clauses found in credit contracts, membership terms, insurance policies and service forms — drafted in advance by one party and presented to the other — are called 'standard terms' (genel işlem koşulları). TBK m.20-25 establishes a special review regime to protect the weaker party.
Definition and Scope — TBK m.20
Standard terms require advance unilateral preparation for use in multiple similar contracts (TBK m.20). Absence of individual negotiation alone does not automatically make every one-off clause a standard term. Actual prior use in another contract is not required.
Standard terms must comply with the nature of the contract, the matter and statutory rules. Review applies regardless of whether they appear in the contract document or a separate document.
'Unwritten' Sanction — TBK m.21-22
For standard terms adverse to the other party to enter the contract, three conditions must be met: (i) the drafter must, at the time of contract, expressly inform the other party of the terms; (ii) provide an opportunity to learn their content; and (iii) obtain the other party's acceptance. Failing any one of these, the standard term is deemed unwritten (TBK m.21/1).
The 'unwritten' sanction is stronger than classical invalidity: the provision is treated as never having been part of the contract. Under TBK m.22, the rest of the contract continues to be valid, and the drafter cannot claim it would not have concluded the contract without the unwritten provision.
Content Review — TBK m.25
Standard terms may not contain provisions contrary to good faith that are adverse to or aggravate the other party's position (TBK m.25). Such terms are invalid even if part of the contract.
Bank fees, insurance, interest variation and early-repayment clauses are subject both to standard-term review and special financial/consumer rules. Not every arrangement fee or early-repayment charge is automatically invalid; the legal basis, cap, disclosure and consent requirements must be assessed for the transaction.
Unfair Terms in Consumer Contracts — TKHK m.5
Article 5 of the Consumer Protection Act (No. 6502) provides stricter protection against unfair terms in consumer contracts. Terms unilaterally inserted without negotiation that, contrary to good faith, cause an imbalance to the consumer's detriment are unfair and absolutely null.
No application by the consumer is required; the court reviews ex officio. In consumer proceedings before the Consumer Arbitration Board or the Consumer Court, unfair terms may themselves form a discrete subject of dispute.
Practical Considerations
In contractual disputes, not only the signed text but also offer correspondence, revision history, invoices, delivery records, payment records, formal notices and the parties' subsequent conduct are taken into account. The formation, performance and termination of a contract often acquire meaning only through these ancillary documents.
Form requirements, authority of representation, penalty clauses, exclusion-of-liability provisions, standard terms and consumer-protection rules may all affect the validity or enforceability of a contract. For standard terms, the requirements of clear information, an opportunity to learn their content and acceptance under Article 21 of the Code of Obligations must be considered, together with any special consumer rules.
Before any dispute arises, the scope of obligations, delivery date, defect notice, default notice, interest and competent-court clauses should be drafted explicitly. Vague provisions may give rise to interpretation disputes and to difficulties of proof later on.
Statutory Provisions
The Turkish version of this page provides the relevant statutory texts or selected excerpts in Turkish. For the current consolidated legislation, our primary reference is mevzuat.gov.tr ; the Official Gazette and relevant court decisions should also be consulted for amendments, commencement and annulment provisions.
Conclusion
Boilerplate 'I have read and understood' acknowledgements no longer provide automatic protection. Showing the standard terms to the other party and negotiating them before signing reduce the risk of later 'unwritten' findings.
This article is for information purposes only and does not constitute legal advice. If you would like professional assistance on a specific matter, you may request a consultation.
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