US OFAC freezes ~$475M in Iran-linked USDT via Tether blacklist on Tron

U.S. authorities have frozen about $475 million worth of USDT linked to Iran in under three months, using Tether’s issuer-controlled blacklist features on the Tron blockchain. On July 14, the U.S. Treasury’s OFAC sanctioned four Tron wallet addresses holding roughly $131 million in USDT. These addresses are tied to Iran’s Central Bank (Bank Markazi). OFAC framed the action as part of efforts to disrupt Iran’s dollar-denominated revenue networks used to evade sanctions. This latest move follows Tether’s earlier April freeze of more than $344 million across two other Tron wallets, also carried out in coordination with OFAC and U.S. law enforcement after the addresses were identified. Tether’s role is central: the USDT issuer can block addresses and prevent tokens from being moved or redeemed, even though balances and wallet addresses remain visible on the public blockchain. In some cases, tokens can also be canceled and reissued at another address—giving U.S. agencies a compliance tool that goes beyond “monitoring” on-chain activity. The sanctions come as U.S.-Iran tensions escalate around the Strait of Hormuz, including renewed restrictions on maritime traffic into and out of Iranian ports. Treasury officials say the broader enforcement campaign, dubbed Operation Economic Fury, targets exchanges, intermediaries, and blockchain addresses involved in moving value into dollar-linked crypto. For traders, the headline risk is regulatory/issuer-control over stablecoins: Tether blacklist actions can rapidly immobilize USDT held on public chains, potentially affecting liquidity and counterparty assumptions around “censorship resistance.”