General rules for making a contract in Türkiye

1) What mandatory elements must a contract between two residents contain?

Most contracts under the Turkish Code of Obligations (TCO) can be made orally or in writing. Moreover, pursuant to Article 2 of the Turkish Code of Obligations, if the parties have agreed on the essential points of the contract, the agreement shall be deemed concluded even if secondary issues have not yet been settled.

To be valid under the TCO, a contract between two residents must include: mutual consent, legal capacity, a definite subject matter, a lawful cause, and compliance with any special form requirements. In addition, for all contracts, the following conditions are required: the parties must have legal capacity; the contract must not contravene mandatory legal rules, public order, general morality, or personal rights; its subject matter must not be impossible; the declarations of intent must be made in a sound and free manner; and the parties’ declarations of intent must not be fictitious or merely apparent (sham transaction)

2) Is notarization or state registration required for B2B contracts?

According to the Turkish Code of Obligations, written form is generally not mandatory for the validity of B2B contracts, and agreements can be concluded orally unless the law explicitly requires otherwise. Notarization or state registration is only necessary in specific cases prescribed by law. For example, a Promise to Sell Real Estate Agreement must be executed in official form before a notary in order to be valid. Similarly, certain contracts involving intellectual property rights, share transfers, or real estate transactions may also be subject to formal requirements. Outside of these exceptions, B2B contracts are valid without notarization or registration, provided that the essential elements of a contract are fulfilled.

3) What are the general requirements for the form and language of a contract between residents?

According to Article 26 of the Turkish Code of Obligations, parties are free to determine the content of a contract, provided that it does not violate mandatory provisions of law, public order, morality, or personality rights. 

Similarly, Article 12 establishes the principle of freedom of form, meaning that contracts are not subject to a particular form unless otherwise required by law.

As a general principle, contracts in Turkish law are subject to freedom of form (Article 12 of the Turkish Code of Obligations). This means that, unless otherwise prescribed, contracts can be concluded in any form (oral, written, or implied by conduct).

However, if a special form requirement exists, it must be expressly stipulated in the Turkish Code of Obligations or another relevant law. Examples include:

• Real estate sale contracts → must be executed in official form before the land registry (Land Registry Law);
• Promise of sale of immovable property → must be executed before a notary public (Article 237 TBK);
• Suretyship contracts → must be in writing and include specific handwritten statements by the surety (Article 583 TBK).

If such a required form is not observed, the contract is deemed null and void (definitively invalid).

Within this framework, it is legally possible for the parties to conclude a contract in a foreign language. However, if the contract is later brought before Turkish courts, it must be translated into Turkish by a sworn translator and notarized in order to be submitted as valid evidence. This may result in additional translation and notary costs during litigation.

To avoid such expenses and for practical convenience, it is common practice in Turkey to draft bilingual contracts (Turkish + a foreign language). This ensures that both parties can understand the contract in their own language while also eliminating the need for extra translation and notarization costs in potential court proceedings.

4) What are the consequences of non-compliance with the written form of a contract?

According to Article 12 of the Turkish Code of Obligations (TCO), contracts are in principle subject to the freedom of form; however, if a specific written or official form is expressly required under the TCO or a special law (for example, suretyship contracts under Article 583 of the Turkish Code of Obligations, promise of sale of immovable property under Article 237 of the Turkish Code of Obligations, or real estate sale contracts under Article 26 of the Land Registry Law ), failure to comply results in absolute nullity . In such cases, the contract produces no legal effect from the outset, cannot be enforced by the parties, and the court must consider its invalidity ex officio.

The legal consequences of nullity are determined by statutory provisions and case law (Court of Cassation precedents). In practice, parties may reclaim payments made under such contracts through unjust enrichment (Articles 77 et seq. of the Turkish Code of Obligations). Furthermore, in situations where the legislator has expressly conditioned the validity of a contract upon compliance with a formal requirement, the absence of such form may also serve as a ground for the contract to be declared null and void, pursuant to the relevant provision of the Turkish Code of Obligations or the applicable special law.

5) What specific rules apply when contracting with public authorities or state customers?

Under Turkish law, the distinction between private law contracts and administrative (public) contracts is clearly reflected in several legal sources. The Turkish Code of Obligations governs private contracts based on the principles of freedom of form and contractual freedom. Public authorities may also conclude such private law contracts (e.g., lease agreements or sales contracts), which are subject to civil courts. However, when the administration contracts for the provision of public services or exercises public authority, the resulting agreements are regarded as administrative contracts. This distinction is grounded in the Constitution (Articles 125 and 155), which provides for judicial review of all administrative acts and assigns jurisdiction to the Council of State (Danıştay) over disputes concerning administrative contracts, and in the Administrative Procedure Law No. 2577 (Article 2/1-c), which expressly subjects disputes arising from administrative contracts to administrative jurisdiction. In addition, specific statutes regulate public contracts, such as the State Procurement Law No. 2886, the Public Procurement Law No. 4734, and the Public Procurement Contracts Law No. 4735. While private contracts remain within the scope of the TCO, contracts concluded under these procurement laws are considered public contracts subject to mandatory administrative law principles.

6) What are the requirements for performance and modification of contracts?

Under Turkish law, the principle of freedom of contract governs the performance and modification of contracts. Parties are generally free to determine the content, terms, and conditions of their agreement, provided that such arrangements do not contravene mandatory provisions, public order, morality, or personal rights. Modification of a contract requires mutual consent of the parties in the same form as required for the validity of the original contract. Contractual performance must comply with the principle of good faith. In cases of delay, partial performance, or impossibility, the rules on default, impossibility of performance and, where relevant, force majeure (not expressly codified but recognized under case law and doctrine) apply. Additionally, Article 138 TCO on hardship (excessive difficulty of performance) allows a party to seek judicial adaptation or termination of the contract where unforeseeable changes fundamentally alter the equilibrium of obligations.

7) What are the requirements regarding currency and payments in contracts with non-residents?

Pursuant to Decree No. 32 on the Protection of the Value of the Turkish Currency and the Communiqué No. 2008-32/34, contracts between residents and non-residents may stipulate payment obligations in foreign currency, unless expressly restricted by the Ministry of Treasury and Finance. Turkish residents are generally prohibited from indexing certain domestic contracts (e.g., real estate leases, employment agreements, service and consultancy agreements between residents) in foreign currency; however, this restriction does not extend to contracts concluded with non-residents. Payment obligations must comply with Turkish foreign exchange regulations, and settlement through authorized banks in Türkiye is required for cross-border transfers. Certain areas remain subject to additional restrictions. For example, the use of foreign currency loans by Turkish residents is limited and subject to eligibility and income requirements, except where specific exemptions apply and crypto-assets are prohibited from being used as a means of payment under regulations issued by the Central Bank of Türkiye.

8) Can foreign law be chosen to govern a contract and what are the restrictions?

Yes, according to International Private and Procedural Law no. 5718 parties are free to choose a foreign law to govern their contractual relations. However, such choice is limited by mandatory provisions of Turkish law and Turkish public policy. Even where foreign law applies, Turkish courts may disregard provisions of the chosen law if they are manifestly incompatible with fundamental principles of Turkish law. Notable restrictions apply, in particular that contracts concerning immovable property in Türkiye are mandatorily governed by Turkish law and subject to its formal requirements, that in employment and consumer contracts foreign law may be chosen only to the extent that the mandatory protective provisions of Turkish law remain applicable, and that certain agreements such as suretyships must in any case comply with Turkish form requirements irrespective of the chosen law.

9) What are the requirements for registration and reporting of cross-border contracts?

Turkish law does not require the registration of all cross-border contracts, but specific reporting obligations may apply depending on the transaction. Foreign direct investments must be notified to the Ministry of Industry and Technology through the E-TUYS system, while mergers and acquisitions that meet certain thresholds require approval from the Competition Authority. Corporate changes such as amendments to articles of association or capital increases are registered with the Trade Registry, and cross-border financial obligations including loans and securities must be reported to the Central Bank via the International Transactions Reporting System. In addition, certain payments may trigger tax reporting obligations such as withholding tax, stamp duty, VAT or transfer pricing documentation. Sector-specific contracts in regulated industries, for example in finance, energy or telecommunications, may also require approval or reporting to the relevant regulator. Non-compliance with these obligations may lead to administrative fines or regulatory sanctions.

Authors: Adil Ali Ceylan, Gülendam Tüylüoğlu, Betul Arslan Aydın, Aigerim Sabit Bikmaz