Jurisdiction Map of Commercial Courts in Istanbul: A Guide to "Where to File a Lawsuit?" Based on Branch – Place of Transaction – Place of Performance 2026

In Istanbul, filing commercial disputes in the "correct court" (jurisdiction) directly affects the speed and strategy of the case. Cases filed in the wrong place are often of jurisdiction ; this results in significant time loss in terms of fees/expenses, notifications, and deadline management. Therefore, in commercial cases, jurisdiction (which district/court?) is as critical as the assigned jurisdiction (Is it the Commercial Court of First Instance?).

In this article, we will construct a "map of authority" by focusing on the three most frequently encountered connection points in Istanbul practice:

• Authorization via branch

• Authorization based on the place of transaction (the place where the commercial relationship is actually conducted)

• Jurisdiction based on the place of performance (the place where the obligation is to be fulfilled)

1) The backbone of jurisdiction in commercial cases: Articles 6, 10, 14, 16 and 17 of the Code of Civil Procedure

In commercial disputes, territorial jurisdiction is mostly by the Code of Civil Procedure (HMK) :

• General jurisdiction: The defendant's place of residence (Code of Civil Procedure, Article 6).

• Lawsuits arising from contracts: The place where the contract is to be performed also has jurisdiction (Code of Civil Procedure, Article 10).

• Branch operations: In lawsuits arising from the operations of a branch, the location of the branch also has jurisdiction (Code of Civil Procedure, Article 14/1).

• Tort (including commercial torts): Alternatives such as the place where the act was committed / the place where the damage occurred / the place of residence of the injured party (Code of Civil Procedure, Article 16).

• Agreement on jurisdiction between merchants: Merchants or public legal entities may authorize one or more courts in writing; as a rule, lawsuits can only be filed in those courts (Code of Civil Procedure, Articles 17-18).

The key idea is this:
In commercial relationships, most lawsuits from contracts (sales, supply, service, lease, work, distributorship, franchise, etc.). Therefore, when determining which commercial court a case should go to in Istanbul, the first checkpoint is usually Article 10 of the Code of Civil Procedure (place of performance) . This is immediately followed by branch connection (Article 14/1 of the Code of Civil Procedure) and, in some cases, tort connection (Article 16 of the Code of Civil Procedure).

---

2) How does "authorization via branch" work?

2.1. If there is a branch transaction: the central court and branch court cases will be heard together

Article 14/1 of the Code of Civil Procedure is clear: In cases arising from the transactions of a branch, the court of the place where that branch is located also has jurisdiction.

In the context of Istanbul, this leads to the following result:

• Even if the company's headquarters are located on the Anatolian side of Istanbul, if the dispute through a branch on the European side , within the judicial district where the branch is located will have jurisdiction.

2.2. Practical criteria for identifying "branch transactions"

In practice, courts do not reduce the definition of "branch operation" to simply the presence of "branch" written on a sign. The following facts become important:

• Signing of the contract by the branch / conducting contract negotiations at the branch

• The order is picked up through the branch, and the shipment/delivery is handled by the branch organization

• The unit issuing the invoice/delivery note must be a branch

• Branch personnel actually managing the performance (e.g., service, maintenance, assembly)

Tip: Even if the word "branch" doesn't appear even once in the contract, evidence (email, quotation form, delivery note, delivery receipt, service report, warehouse exit records) can bring you 14/1 of the Turkish Code of Civil Procedure .

---

3) Why is the "place of operation" important? (It's not a rule in itself, but it helps you find the right rule.)

The phrase "place of processing" may not seem like a standalone authorization clause in the law; however, in Istanbul, the most functional guidelines . This is because the place of processing allows you to determine the following:

• the transaction conducted through a branch ? → Article 14/1 of the Code of Civil Procedure comes into play.

• Did the dispute arise from a contract or from a commercial tort ? (e.g., unfair competition, trademark/domain name redirection, attack on trade reputation, data breach, etc.) → Article 16 of the Turkish Code of Civil Procedure opens up the options.

• If a contractual relationship exists, the actual execution serves to indicate the "place of performance" → this is linked to Article 10 of the Code of Civil Procedure.

In short, the place of the transaction is often the area of ​​evidence that leads to the correct jurisdiction.

---

4) How to find the "place of performance"? (The most common key to determining Istanbul jurisdiction)

Article 10 of the Code of Civil Procedure opens the door for you to say: "Lawsuits arising from contracts may also be filed in the court of the place where the contract is to be performed."

So what happens if the contract doesn't explicitly state a "place of performance"? The answer is Article 89 of the Turkish Code of Obligations.

4.1. Turkish Code of Obligations, Article 89: General rule regarding the place of performance

According to Article 89 of the Turkish Code of Obligations, if there is no determination by the will of the parties:

• Monetary debts: At the creditor's place of residence at the time of payment.

• Partial debts: Where the subject matter of the debt is located at the time the contract is concluded.

• Other debts: These are payable at the debtor's place of residence at the time the debt arose.

This clause also contains an important safety valve: if the creditor's subsequent change of residence "significantly complicates" performance, the debt may be performed at the creditor's previous place of residence

4.2. Definition of "place of performance" in commercial disputes

In commercial cases in Istanbul, the place of performance is usually defined as follows:

• Goods delivery/supply: Delivery address (warehouse, construction site, store, depot)

• Service contracts: Location where the service is actually provided (e.g., maintenance/repair, installation, consulting site)

• Construction/manufacturing contracts: The place where the work is performed (construction site/facility)

• Monetary debt (amount/receivable): According to Article 89 of the Turkish Code of Obligations, this is often determined by the creditor's place of residence at the time of payment (unless otherwise stipulated in the contract).

Strategic outcome: In the same case, the defendant's domicile (Article 6 of the Code of Civil Procedure), the place of performance (Article 10 of the Code of Civil Procedure), and the branch (Article 14/1 of the Code of Civil Procedure) can all be considered simultaneously. This creates a "discretionary jurisdiction" area for the plaintiff.

---

5) Jurisdiction Map in Istanbul: District → Courthouse area → Commercial Court

Now let's get to the critical practical question: "The place of performance/branch/transaction is in this district; which courthouse in Istanbul do I go to?"

The following mapping is based on the district-court district connections in the Judicial Guide . Additionally, the information regarding the HSK (Supreme Council of Judges and Prosecutors) judicial district update , as mentioned in the Istanbul Bar Association's announcement, which includes Eyüpsultan within the Gaziosmanpaşa basin, should also be taken into consideration.

5.1. European Side – court districts (practical distribution of commercial cases)

A) Istanbul Courthouse area

Districts: Bayrampaşa, Beşiktaş, Beyoğlu, Fatih, Kağıthane, Sarıyer, Şişli.

Note: This list is based on the announcement stating that, following a decision by the HSK (High Council of Judges and Prosecutors), Eyüpsultan was removed from this jurisdiction and included in the Gaziosmanpaşa Courthouse jurisdiction

B) Gaziosmanpaşa Courthouse basin

Districts: Arnavutköy, Gaziosmanpaşa, Sultangazi , and Eyüpsultan.

C) Bakırköy Courthouse basin

Districts: Bakırköy, Bahçelievler, Bağcılar, Güngören, Esenler, Zeytinburnu.

D) Küçükçekmece Courthouse area

Districts: Küçükçekmece, Başakşehir, Avcılar.

E) Büyükçekmece Courthouse basin

Districts: Büyükçekmece, Beylikdüzü, Esenyurt.

5.2. Anatolian Side – courthouse area

Istanbul Anatolian Courthouse basin

Districts (according to the guide): Ataşehir, Çekmeköy, Kadıköy, Kartal, Maltepe, Pendik, Sancaktepe, Sultanbeyli, Tuzla, Ümraniye, Üsküdar; also the annexes of Adalar, Beykoz, and Şile.

---

6) Practical decision tree for "Where should I file a lawsuit?"

Step 1: Is there an authorization agreement?

the parties are merchants and the contract contains a written jurisdiction clause , then, in most cases, only those courts have jurisdiction according to Articles 17-18 of the Code of Civil Procedure.

Note: Authorization agreements cannot be made in cases of absolute authorization or matters that cannot be resolved through other means.

Step 2: Is there a branch transaction involved?

If the dispute arises from the transactions of a branch, the location of the branch is also competent (Code of Civil Procedure, Article 14/1).
The district where the branch is located → find the court district on the map above → the relevant Commercial Court of First Instance.

Step 3: Determine the "place of performance" if a contractual relationship exists

According to Article 10 of the Code of Civil Procedure, the court of the place of performance has jurisdiction.
When determining the place of performance, remember Article 89 of the Turkish Code of Obligations: In monetary debts, payment is generally made at the place of residence; in delivery/work obligations, the nature of the contract and the work are the determining factors.
Place of performance district → court district on the map → relevant Commercial Court of First Instance.

Step 4: If multiple options appear, choose the "strongest connection"

More than one competent court may emerge in the same case:

• Defendant's place of residence (Article 6 of the Code of Civil Procedure)

• Place of performance (Article 10 of the Code of Civil Procedure)

• Branch (HMK 14/1)

• Options for torts (Article 16 of the Turkish Code of Civil Procedure)

In this situation, the location of the evidence, ease of access to witness/delivery/service records, and enforceability make a practical difference when making a choice.

Step 5: Manage the risk of jurisdictional disputes

In cases where jurisdiction is uncertain, the opposing party must raise the objection to jurisdiction in their response ; otherwise, the right to object is lost. For the plaintiff, establishing a solid foundation from the outset (place of performance, branch transaction, invoice/delivery evidence) significantly reduces the likelihood of a lack of jurisdiction.

---

7) Three typical scenarios in the Istanbul case

Scenario 1: “Sales/delivery via branch” (Articles 14 + 10 of the Turkish Code of Civil Procedure)

The offer/invoice prepared by the branch, the shipment from the branch warehouse, the delivery and receipt by the branch personnel…
→ Authorization arises both through the branch district and the delivery (performance) location.

Scenario 2: “Dispute over monetary claim – place of payment” (Turkish Code of Obligations Article 89 + Turkish Code of Civil Procedure Article 10)

If the place of payment is not explicitly stated in the contract, Article 89 of the Turkish Code of Obligations applies to monetary debts; in most cases, the creditor's place of residence at the time of payment is considered the place of performance.
→ The correct court district in Istanbul is selected based on the district where the creditor's headquarters are located.

Scenario 3: “Commercial tort – unfair competition / reputational attack” (Code of Civil Procedure, Article 16)

The location where the damage occurred, the place where the act was committed, or the place of residence of the injured party become alternative options.
→ In digital breaches, since the "location where the damage occurred" can be debatable, the evidence strategy (access logs, customer loss, notice of default, platform correspondence) becomes important.

---

 In Istanbul, the right commercial court is found with the right "point of contact"

In Istanbul, two steps are all it takes to read the geographical jurisdiction in commercial lawsuits like a "map":

1. jurisdiction rule (Code of Civil Procedure 6 / 10 / 14 / 16 / 17).

2. Convert the district where the place of performance/branch/operation was found to the courthouse area (Judicial Guide + current HSK judicial district announcements).