The U.S. government froze about $131 million in Tether on the Tron blockchain Monday, targeting wallets it says are tied to Iran’s central bank. The Treasury Department’s Office of Foreign Assets Control sanctioned four addresses, marking the latest move in a campaign that has seen authorities seize or freeze nearly $1 billion in cryptocurrency connected to Iran since late May.
How Tether helps enforce sanctions
Tether can blacklist addresses and prevent tokens from moving, even though the wallet and its balance remain visible on the blockchain. In certain cases, the company can cancel tokens at one address and issue an equivalent amount at another — effectively letting law enforcement take control of the value. That’s a power Bitcoin doesn’t have. No central company can stop a Bitcoin transaction.
This isn’t the first time Tether has worked with U.S. authorities on Iran-related freezes. In April, Tether froze over $344 million across two other Tron wallets in coordination with OFAC and U.S. law enforcement. The latest action brings the total frozen in less than three months to about $475 million.
Operation Economic Fury
The Treasury Department launched Operation Economic Fury in June, sanctioning four Iranian crypto exchanges — Nobitex, Bitpin, Ramzinex, and Wallex — for helping Iran evade sanctions. Treasury said Nobitex processed more than half of Iran’s crypto inflows in 2025 and helped the Central Bank of Iran acquire hundreds of millions in stablecoins.
Chainalysis estimated Iran’s cryptocurrency ecosystem received over $7.78 billion in 2025. Addresses linked to the Islamic Revolutionary Guard Corps accounted for about half of Iran’s crypto activity in Q4 2025 and received over $3 billion that year.
Maritime restrictions resume
Separately, U.S. Central Command resumed restrictions on maritime traffic entering and leaving Iranian ports beginning July 14, after fresh strikes against Iranian military targets. Treasury Secretary Scott Bessent said OFAC targeted the wallets as part of a broader effort to disrupt revenue networks Iran uses to evade sanctions.
Bessent said by late May the U.S. had seized or frozen nearly $1 billion in cryptocurrency connected to Iran through the campaign. Monday’s freeze adds to that tally, but it’s unclear how much more remains in wallets the U.S. hasn’t yet identified.
