Treasury cuts crypto exchange MEXC off from US financial system over $16 billion in illicit flows

The United States Treasury has moved to cut one of the world's largest cryptocurrency exchanges off from the American financial system, accusing the platform of processing more than $16 billion in transactions tied to sanctions evasion by Russia, Iran and North Korea over the past five years.

The Treasury's Financial Crimes Enforcement Network, known as FinCEN, said in an order issued Friday that it is barring U.S. financial institutions from processing any funds transfer to or from MEXC Global, a Seychelles-registered exchange that ranks among the top 20 crypto trading platforms by volume. The action, part of a campaign the agency calls Operation Economic Outcast, does not freeze MEXC's assets or add the exchange to the Treasury's sanctions list. Instead, it uses a narrower but increasingly favored tool: declaring a foreign financial entity a "primary money laundering concern" and severing its access to U.S. dollar clearing.

Treasury Secretary Scott Bessent framed the action in blunt terms in the Treasury's press release announcing the order.

"Either you support the Iranian regime, or you have access to the U.S. financial system," Bessent said, adding that Treasury would "continue to sever the Iranian regime's economic lifelines."

The allegations, by the numbers

According to FinCEN's order, MEXC facilitated at least $16 billion in illicit transactions between May 2021 and May 2026. The agency broke the figure down by jurisdiction. Roughly $1.5 billion was linked to Russian sanctions evasion, including $232 million in direct transactions with entities already sanctioned by the United States, the European Union or the United Kingdom. FinCEN said MEXC continued processing transactions involving the sanctioned Russian exchange Garantex and its rebranded successor, Grinex, as recently as June 2026, more than four years after the Office of Foreign Assets Control first designated Garantex. The order also cites nearly $200 million in transactions connected to A7A5, a ruble-pegged stablecoin, and about $26 million benefiting the sanctioned A7 payment network.

On the Iran side, FinCEN said MEXC carried out roughly $1 billion in direct transactions with more than 40 identified Iranian virtual-currency exchangers, some of which are themselves under sanction. About $22 million of that flow, the agency said, benefited Iran's central bank and the Islamic Revolutionary Guard Corps' Qods Force. The order adds further allegations involving North Korean sanctions evasion, ransomware payments and darknet-market activity, though it provides less dollar detail on those categories.

Founded in 2018, MEXC says it processes more than $1 billion in trading volume daily and holds about $5 billion in reserves, offering more than 3,000 tokens across more than 50 fiat currencies. FinCEN said the exchange's public anti-money-laundering policies, which claim to bar users from jurisdictions including Iran and North Korea, were undercut by "severe deficiencies" in its actual compliance controls. MEXC had not issued a public response to the order as of Sunday.

Part of a wider campaign against crypto's shadow rails

The MEXC order is the latest step in a Treasury campaign that has spent much of the autumn targeting the infrastructure Moscow has built to move money around Western sanctions using digital assets. On October 1, Treasury's Office of Foreign Assets Control designated Russia's A7 Network, a payment system Treasury says is led by the sanctioned businessman Ilan Shor, as a significant transnational criminal organization. FinCEN said in that action that more than 180 entities tied to the network processed at least $179 billion through the A7A5 stablecoin between February 2025 and June 2026, and that Iran's central bank and Revolutionary Guard had used the network's services. MEXC's dealings with Garantex, Grinex and the A7A5 token, as described in Friday's order, place the exchange inside that same web of entities Treasury has spent recent months trying to isolate.

Crypto-industry analysts note that Friday's order is a meaningfully different instrument from a standard sanctions designation. It does not add MEXC's officers or wallets to the Specially Designated Nationals List, and it does not compel other governments to act. Decrypt, which first flagged the order's text in detail, noted that offshore users may still be able to trade on MEXC peer to peer, but that any bank still willing to clear dollars for the exchange now carries direct legal exposure. Cointelegraph's reporting on the order similarly described it as a chokehold on MEXC's dollar on-ramps rather than a global asset freeze.

Who the order touches

The immediate targets are U.S. banks and payment processors, which the order prohibits from transmitting funds involving MEXC once it takes effect. That reaches any American correspondent bank, clearing house or fintech that still routes dollars to or from the exchange on behalf of customers, and it creates civil and criminal liability for institutions that do not comply. The order leaves existing Bank Secrecy Act reporting duties and OFAC sanctions programs untouched; it adds a new restriction on top of them.

For MEXC's customers, the practical effect will depend heavily on how exposed they are to the U.S. dollar system. Traders using non-dollar funding rails, or operating entirely outside U.S. jurisdiction, may see limited disruption in the near term. Those relying on U.S. banks or dollar-denominated stablecoin on-ramps to move funds onto or off the platform face a narrowing set of options as American financial institutions move to comply. The broader digital-asset industry, which has spent much of 2026 lobbying Washington for clearer rules rather than case-by-case enforcement actions, is likely to read the order as a signal that Treasury intends to keep using targeted financial-access restrictions against offshore exchanges it views as inadequately policing illicit flows.

What happens next

The order takes legal effect 30 days after it is published in the Federal Register, giving MEXC and the banks that service it a short window to unwind remaining dollar-linked exposure. FinCEN's release also points users and industry insiders toward the agency's whistleblower program, which can pay awards to people whose tips lead to penalties exceeding $1 million in sanctions or Bank Secrecy Act cases, including tips involving Iranian proxies operating outside Iran.

Treasury officials have signaled that MEXC is unlikely to be the last target of Operation Economic Outcast. The department has already blacklisted the Iranian exchange Nobitex and proposed a rule that would cut off companies linked to the A7 Network more broadly, a measure that one industry estimate says could eventually bind more than 300,000 U.S. financial institutions if finalized. For now, the MEXC order stands as the clearest example yet of Treasury using the funds-transfer restriction, rather than a sanctions listing, as its preferred tool for pressuring crypto platforms it says have become conduits for Russian, Iranian and North Korean money.