Secondary Sanctions Explained: Primary vs Secondary (2026)

A Singaporean logistics firm arranges a shipment for a Turkish manufacturer. The goods are construction materials, the buyer is in Central Asia, and every part of the deal is legal under local law. Then, silence. Six months later, the firm’s U.S. dollar accounts are frozen. Why? The U.S. Treasury determined the final buyer was a front company for a sanctioned Russian entity. The Singaporean firm just learned a brutal lesson in secondary sanctions.

Primary sanctions are simple. They apply to a country's own citizens and companies, telling them who they can't do business with. Secondary sanctions are different. They target foreign companies—third parties—threatening to sever their access to a critical market, like the U.S. financial system, if they deal with those same sanctioned targets.

Primary Sanctions - A set of legal restrictions that apply to persons and entities directly under the jurisdiction of the `sanctioning state` (e.g., its citizens, residents, and corporations). These rules prohibit them from engaging in specific activities with sanctioned countries, entities, or individuals, regardless of where the activity occurs.

Secondary Sanctions - Measures that a `sanctioning state` applies to non-domestic `third parties` (e.g., foreign banks or companies) to prevent them from dealing with targets of its primary sanctions. Enforcement is not through traditional legal penalties but by threatening to restrict the third party's `market access` or `banking access` within the sanctioning state's economy.

What's the Real Difference Between Primary and Secondary Sanctions?

The distinction boils down to jurisdiction versus influence. Primary sanctions are a direct exercise of legal authority over a country's own people. Secondary sanctions are pure economic statecraft, a tool to project foreign policy influence and force companies in other countries to align with the sanctioning state's objectives.

Primary sanctions are straightforward. If you are a "U.S. Person"—a citizen, resident, or American company—you are legally barred by your own government from dealing with anyone on the Specially Designated Nationals (SDN) List. A violation isn't just a slap on the wrist; it can lead to massive fines and even prison time, decided in a U.S. court.

Secondary sanctions operate in a gray area. They don't allege that a foreign company in, say, Malaysia or Brazil, has broken U.S. law. Instead, they present a stark commercial choice: keep doing business with a U.S.-sanctioned entity, and you risk losing all access to the U.S. dollar, American investors, and the entire U.S. market.

Who do secondary sanctions apply to?

These sanctions target non-U.S. persons. Think foreign financial institutions, manufacturers, shipping companies, insurers, and tech firms that may have no direct U.S. nexus whatsoever.

The goal is to completely isolate the primary target, making them too toxic for anyone in the global marketplace to touch. For most international businesses, the choice between one client in a sanctioned country and retaining access to the world's largest economy is, on paper, a simple one. In practice, it means abandoning potentially profitable, long-term relationships overnight.

How Do Secondary Sanctions Actually Work in Practice?

The United States is the world's most prominent and powerful user of this tool. Its process is run mainly by the U.S. Department of the Treasury's Office of Foreign Assets Control (OFAC).

When OFAC decides that a foreign entity has engaged in a "significant transaction" with a person under U.S. primary sanctions, it can impose various penalties. The true weapon isn't a fine; it's designation on the SDN List. This move effectively serves as an economic death sentence. It prohibits any U.S. person from dealing with the newly listed foreign entity and freezes any of its assets that touch U.S. jurisdiction. Another crippling penalty is the loss of correspondent banking accounts, which instantly cuts off a company's ability to transact in U.S. dollars.

This aggressive approach contrasts sharply with that of the European Union. The EU has a strong framework for primary sanctions but is deeply reluctant to use secondary measures. In fact, the EU has often viewed the extraterritoriality of U.S. secondary sanctions as an attack on its own sovereignty, going so far as to enact "blocking statutes" to protect EU companies from them.

What is an example of a secondary sanction?

The U.S. sanctions against Iran provide a clear, real-world example. Picture a German engineering firm that sells specialized industrial pumps to an Iranian company—a transaction perfectly legal under German and EU law. Later, the U.S. Treasury determines the Iranian buyer is secretly controlled by the Islamic Revolutionary Guard Corps (IRGC), an entity on OFAC's SDN list.

OFAC could then designate the German firm for providing material support to the IRGC. The consequences would be immediate and brutal:

• All U.S. persons and companies would be prohibited from doing business with the German firm.
• The firm's U.S. bank accounts would be frozen instantly. Any U.S. dollar payments in transit, anywhere in the world, could be seized.
• Even without a direct U.S. link, international banks would likely refuse to process payments for the firm to avoid their own risk, crippling its global operations within days.

Are Secondary Sanctions Legal Under International Law?

Here, the consensus shatters. The legality of secondary sanctions remains one of the most divisive issues in international economic law.

Critics, including the European Union and other close U.S. allies, argue their extraterritoriality violates bedrock principles of state sovereignty. By trying to apply U.S. policy to actors and transactions with no U.S. nexus, they contend America is overstepping its bounds. In their view, only the United Nations Security Council has the authority to impose such globally binding measures.

Proponents, led by the United States, see it differently. They defend these sanctions as an essential foreign policy tool, especially when multilateral action through the UN is blocked by a veto. In this view, states must have a way to confront threats to their national security, like nuclear proliferation, terror financing, or human rights atrocities.

While these disputes rarely end up at the International Court of Justice, legal challenges do happen. Sanctioned companies have fought back in national courts or regional bodies like the European Court of Human Rights (ECHR), often arguing the designation lacked due process or violated property rights. The EU itself bases its own sanctions framework on legal acts published in EUR-Lex, which also provides the foundation for its countermeasures like the Blocking Statute.

What Are the Top Compliance and Legal Risks for Businesses in 2026?

For any company operating internationally, the primary legal risk as of 2026 is the sheer, unpredictable complexity of the sanctions landscape. Geopolitical friction, especially concerning Russia and China, has made economic sanctions a frontline weapon of statecraft. Businesses are getting ensnared in conflicts they have no direct part in.

This creates a crushing compliance risk. A transaction that is perfectly legal in your home country can trigger devastating penalties from a sanctioning state. To manage this, global firms now need far more sophisticated due diligence. It’s no longer enough to know your customer (KYC). You must know your customer's customers (KYCC) and the ultimate end-user of your products. The problem is that proving this ultimate end-user can be nearly impossible without intrusive investigations that can alienate your legitimate business partners.

The risk landscape has exploded. A decade ago, sanctions compliance was about a few heavily sanctioned countries like Iran and North Korea. Today, sanctions hit major global economies. This means a much wider range of businesses—from banking and insurance to tech and logistics—are in the crossfire.

What is an OFAC secondary sanction?

An "OFAC secondary sanction" is not a penalty for breaking U.S. law, because the foreign target is outside American jurisdiction. It is a foreign policy designation imposed by the U.S. Treasury's Office of Foreign Assets Control. This designation is a public declaration that a foreign person or entity has acted against U.S. national security interests, perhaps by dealing with a sanctioned Russian bank or Iranian paramilitary group. The consequence is simple: you are blacklisted from the U.S. financial and commercial system.

This article is published by an independent law firm for informational purposes only and does not represent or claim affiliation with any government body, international organization, or official authority.

Frequently Asked Questions

How do you comply with secondary sanctions?

Compliance requires a dynamic, risk-based approach. It involves screening all parties against global sanctions lists, conducting deep supply chain due diligence, and embedding strong sanctions clauses in contracts. Most importantly, it often means making the difficult choice to forgo business that may be legal locally to preserve vital market access to the U.S. or other major economies.

What is the main purpose of sanctions?

The main purpose is to change the behavior of a target—a state, regime, or organization—without going to war. Sanctions are a tool to alter strategic decisions. The stated goals often include deterring nuclear proliferation, countering terrorism, promoting human rights, and upholding international law.

How are Interpol notices different from economic sanctions?

It's easy to confuse these, but they operate in completely different worlds. Think of it this way: sanctions target your money, while an Interpol notice targets you. Economic sanctions are a foreign policy weapon. Governments, like the U.S. or blocs like the EU, use them to freeze assets and block transactions. An Interpol notice, however, is a law enforcement tool. It’s a global alert from police to other police, asking them to find and potentially arrest someone pending extradition. One is about financial restriction, the other is about physical liberty.