Twenty-four Türkiye-based companies are now on the US sanctions list for Iran. Few of them are defence firms, and none of their assets in Türkiye is frozen by the listing itself.

Key points

• Between February and October 2026, the United States listed at least 24 Türkiye-based companies under its Iran sanctions programmes. Fifteen of them were added after 24 August.
• An OFAC listing blocks assets and dealings within US reach. It does not freeze anything in Türkiye. Only a decision under Turkish law, published in the Resmî Gazete, can do that.
• For most of the 2026 listings, Turkish law provides no route to such a decision. Commercially, however, the company can lose dollar payments, banking relationships and US-linked suppliers within days.
• Removal from the list (delisting, listeden çıkarılma) is possible, but it depends on evidence of a genuine change in circumstances that the company starts building on day one.

The numbers behind the headlines

The US Treasury’s Office of Foreign Assets Control (OFAC) and the State Department have used nine separate actions this year to list Turkish companies on the Specially Designated Nationals and Blocked Persons List (the SDN List, often called the OFAC yaptırım listesi).

Activity	Turkish companies listed	Legal basis
Trading or shipping Iranian petrochemicals and petroleum products	12	E.O. 13846 (State Department)
Paying for or supplying Iran’s missile, drone and weapons procurement	5	E.O. 13382 (non-proliferation)
Banking: an investment bank and two subsidiaries	3	E.O. 13902 (Iran’s financial sector)
Aviation and logistics services for Mahan Air	3	E.O. 13224 (counter-terrorism)
Supplying truck parts into Iran’s automotive sector	1	E.O. 13902 (automotive sector)

Several Turkish nationals and Istanbul residents were listed alongside these companies as owners, managers or exchange house operators.

The pace has changed sharply. Treasury launched its campaign against Iran’s economic lifelines, Operation Economic Outcast, on 24 August 2026. Since then, six actions have reached Türkiye: four petrochemical companies on 24 August, the bank on 4 September, the aviation firms on 8 September, a defence trading company on 29 September, an auto parts supplier on 1 October and three more petrochemical importers on 8 October.

Why Türkiye is in the frame

The listings follow the war. United States and Israeli strikes on Iran began on 28 February 2026, a ceasefire held from 8 April, and on 13 July Washington resumed strikes and reimposed its blockade of the Strait of Hormuz. Indirect talks were still running through Qatari mediation in early October, but sanctions pressure has only grown.

Operation Economic Outcast widened the legal net in three ways that matter to Turkish business.

More sectors. Under Executive Order 13902, Treasury can now sanction any person, anywhere, who operates in a designated sector of the Iranian economy. Five sectors were added on 24 August (digital assets, technology, gold, aviation and shipping) and two more on 1 October (automotive and rail). They sit alongside the financial, petroleum and petrochemical sectors already covered. A Turkish company no longer needs to be part of a weapons network to be listed. Selling truck parts was enough on 1 October.

Direct pressure on governments. Treasury announced that every country would be given a defined timeline to shut down the Iran-related activity it had identified, and that Treasury would act itself if they did not.

Direct pressure on banks. On 5 October, OFAC issued an alert to foreign financial institutions doing business with Iran. It warns that such institutions “could be targeted at any time without advance notification” and “should take immediate action to terminate such activity and relationships”. The alert cites the Turkish investment bank listed in September as an example. Behind it sits the threat of secondary sanctions (ikincil yaptırımlar): a foreign bank that knowingly facilitates a significant transaction for a listed person can lose its US correspondent and payable-through accounts, and with them its access to the dollar.

Türkiye’s position explains the rest. Its border and trade with Iran, its gold market, its airports and its logistics sector make it a natural transit point. Treasury’s own releases describe Iranian oil revenue moving through Hong Kong to the UAE and Türkiye, where it is converted into gold and cash.

Who actually gets listed

Very few of the 24 are what a screening officer would expect.

Payers, not manufacturers. In February, a customs broker, a food company and a textile machinery trader were listed for one reason: they paid for sensitive machinery bought for the maker of Shahed drone engines. One sent more than USD 1 million.

Ordinary goods with a military use. A cotton linter exporter was listed in April. Cotton linters appear on no control list, but they are processed into nitrocellulose for solid-fuel rocket motors.

Young companies with foreign owners. The defence trading company listed on 29 September was formed in Istanbul in June 2025. Its sole shareholder is the chairman of a Pakistani defence group that, according to Treasury, procures weapons for Iran’s Ministry of Defense. One of the aviation firms was set up in İzmir in July 2024.

Agents and forwarders. Mahan Air’s general sales agent and the forwarder that coordinated its shipments, including drone components, were listed on 8 September.

Past trades, listed today. The three importers listed on 8 October bought between roughly USD 3.5 million and USD 20 million of Iranian-origin petrochemicals in 2023 and 2024. The listings came two years after the trades.

That last point is the one most businesses miss. Exposure is measured against conduct the US government has already mapped, and the mapping reaches back years. Clean trading today does not protect a company from transactions recorded in 2023.

What an OFAC listing does

The SDN listing takes effect through US jurisdiction:

• Property of the listed company in the United States, or held by a US person anywhere, is blocked and must be reported to OFAC.
• Any company owned 50 per cent or more by one or more listed persons is blocked automatically, even if it is not named (the 50 per cent rule).
• US persons may not deal with the listed company. Neither may transactions that pass through the United States, which in practice catches dollar payments cleared through US banks.
• Turkish subsidiaries of US companies are bound directly. Under the Iranian Transactions and Sanctions Regulations, a foreign entity owned or controlled by a US person is generally prohibited from dealing with Iran as if it were a US person.
• Non-US persons commit a violation if they cause a US person to breach the sanctions or act to evade them. Civil liability is strict.

For a Turkish company that settles in dollars, banks with an internationally active Turkish bank or buys from US-linked suppliers, these effects arrive almost immediately, although no Turkish authority has acted.

What an OFAC listing does not do: the asset freeze question in Türkiye

An OFAC listing does not freeze assets in Türkiye. An asset freeze (malvarlığının dondurulması) over property located in Türkiye needs a decision under Turkish law, and Turkish law offers two routes only.

Law No. 6415 on the Prevention of the Financing of Terrorism. Article 5 gives effect to UN Security Council terrorism listings. Article 6 allows a foreign government to request a freeze. The request must be reasoned and sent through the Ministry of Justice or the Ministry of Foreign Affairs. The Evaluation Commission assesses it, the President decides, and reciprocity applies. Under Article 11, the decision is published in the Resmî Gazete and treated as notified on publication.

Law No. 7262 on the Prevention of the Financing of the Proliferation of Weapons of Mass Destruction. Article 3 gives effect to UN Security Council listings by a Presidential decision published in the Resmî Gazete. There is no mechanism for a foreign state’s request. The FATF’s 2026 evaluation of Türkiye found that the Iran-related freezing decrees still refer to Resolution 2231 rather than to the Resolution 1737 regime restored in September 2025.

Applied to the 2026 listings:

US legal basis	Turkish companies	Route to a freeze in Türkiye
E.O. 13846	12	None
E.O. 13902	4	None
E.O. 13382	5	Law 7262, only if the company is also listed by the UN Security Council
E.O. 13224	3	Law 6415 Article 6, only on a US request and a published Presidential decision

The test is simple. If no decision naming the company has been published in the Resmî Gazete, its assets in Türkiye are not frozen under Turkish law.

A closed account is not a frozen account

When a Turkish bank refuses a transfer or ends its relationship with a listed customer, it is managing its own secondary sanctions risk under its contract and risk policy. It is not executing a freezing order, because none exists.

The difference decides the response. A company can challenge an unlawful freeze. It cannot force a bank to keep a relationship the contract allows the bank to end. What it can do is negotiate the orderly release of balances, the settlement of receivables and the transfer of funds owed to it.

Turkish regulators also keep powers of their own. Twelve days after the investment bank was listed, the Banking Regulation and Supervision Agency (BDDK) decided on 16 September 2026, under Article 18(5) of Banking Law No. 5411, that the Savings Deposit Insurance Fund (TMSF) would exercise the shareholder rights, other than dividend rights, attached to 99.98 per cent of its shares. Ownership did not pass and the licence was not revoked. Sanctions law froze nothing; banking law took over governance. Financial institutions should expect the same pattern: supervisory action under the regulator’s own statute, rather than a sanctions freeze.

UK and EU exposure is separate

UK and EU businesses are not bound by OFAC listings, but they are bound by their own regimes, and those have tightened too. The UK’s Iran (Sanctions) (Amendment) Regulations 2026 took effect on 29 September 2026. They add restrictions on oil, petrochemicals, gold, precious metals, maritime goods and sectoral software, as well as limits on correspondent banking and a broad insurance ban. A Turkish exporter selling into the UK or EU, or banking through London or Frankfurt, should screen against UK and EU lists as well as the SDN List and treat each result on its own legal basis.

Protecting the business: defence, dual-use and industrial exporters

Look behind the shareholder register. Identify ultimate owners and directors, their other companies and where those companies trade. A recently formed company wholly owned by a foreign defence executive is a recognised risk pattern.

Refuse third-party payments. If an unrelated Turkish company, especially a customs broker or a food trader, offers to pay the price, treat it as a sign of concealed end use and refuse or escalate.

Screen end use, not just classification. Uncontrolled inputs such as cotton linters and truck parts have led to listings. Iran’s technology, automotive and rail sectors are now designated sectors in their own right.

Apply the same diligence to agents and forwarders. Distributors, freight forwarders and sales agents act in your name. Three listings on 8 September came from agency and logistics roles alone.

Review the last three years of Iran-linked trade. The October petrochemical listings rested on 2023 and 2024 imports. A confidential look-back now lets a company assess its exposure, end any residual business and prepare its position before a listing.

Draft contracts for a listing. Include an immediate termination right if the counterparty or its owners are listed, a duty to notify any listing, and a requirement that payments come only from the named counterparty’s named account.

Protecting the business: banks, payment institutions and exchange offices

Keep two screens and two records. Turkish freezing decisions under Laws 6415 and 7262 are legal obligations and must be executed. OFAC matches are risk decisions. Each needs its own procedure and a record of the basis for every decision.

Apply the 50 per cent rule. A name-only screen will clear unnamed subsidiaries that US rules treat as blocked.

Review correspondent and nested relationships. The Turkish bank listed in September was designated for providing correspondent services to Iranian banks. The 5 October alert makes clear that such services, including to Iranian banks’ branches and subsidiaries in third countries, can lead to sanctions without warning.

Bring gold and exchange activity into scope. Gold is now a designated sector. Two Türkiye-linked individuals were listed in May for roles in an Iranian exchange house, and the FATF found in 2026 that Türkiye’s Group B exchange offices are not required to run a compliance programme. Banks serving those offices carry that gap.

Be ready for supervisory questions. Requests linked to Treasury’s country timelines are likely to arrive through BDDK, MASAK or correspondent banks. Institutions should be able to show which Iran-related activity they identified and how they ended it.

If your company is listed: the first steps and the road to delisting

Read the entry. The SDN entry shows the designating agency, the executive order, the programme tags and any linked party. These determine the 50 per cent consequences for subsidiaries, the risk your counterparties face and the case you must answer.

Establish the Turkish position. Check the Resmî Gazete. Without a Turkish decision there is no Turkish freeze. Contact your banks before they decide alone, and identify which relationships can be ended under contract and which payments are owed to you.

Do not move assets to avoid the listing. For a non-US person, evasion is a violation in itself, and it will count against any later petition.

Start the delisting file at once. Removal is sought under 31 CFR 501.807 through OFAC’s Reconsideration Portal. The petition must show that the designation lacked a sufficient basis or that circumstances have changed since it was made. OFAC checks completeness within seven to ten business days, may send questionnaires within 90 days of opening the file, decides whether to meet the petitioner and issues a written decision. There is no deadline, and OFAC warns that review can be lengthy.

A change in circumstances must be real and documented. Ending the Iran business, the exit of the owners or managers named in the listing, an independent review of past transactions and a working compliance programme are the facts OFAC weighs. Public denials do not change the record.

Delisting does happen, including during this campaign. OFAC removed Turkish persons from its Russia-related listings in March, took 84 entries off the SDN List in July and, on 8 October, removed two container ships from its Iran listings. Treasury repeats in every release that the goal of sanctions is a change in behaviour. That is the standard a well-prepared petition meets.

How Herdem can help

Herdem Attorneys at Law advises Turkish and international companies, defence and dual-use exporters, banks and payment institutions on US, UK and EU sanctions. Our work includes:

• confidential Iran exposure reviews and look-backs before any listing;
• immediate response when a client, counterparty or subsidiary is listed, including the Turkish-law position on freezes and bank exits;
• OFAC delisting petitions and the compliance evidence they require;
• sanctions compliance programmes, contract clauses and screening procedures.

To discuss a listing, a counterparty concern or a compliance review in confidence, contact our Istanbul office on +90 212 306 3152 or through herdemlaw.com.

This article reflects the position as at 26 October 2026. It is general information and does not constitute legal advice.