- Tether says roughly $550m of Iran-linked USDT was frozen during 2026. Its own statement itemises about $474m of that.
- Democratic staff on a Senate subcommittee analysed 846 sanctioned or seizure-targeted wallets and referred Tether to the Treasury and Justice departments.
- A referral is not an open investigation, and nobody has found that Tether broke any law.
Most people who hold USDT hold it for an hour at a time, parked between trades. On 28 September two documents landed about what the company behind that can do to a balance, and they were published within hours of each other, saying close to the opposite.
If your USDT address is ever caught up in a sanctions net, the tokens do not leave your wallet. They simply stop being movable, because the issuer switched them off at the contract level. No court order is needed for that, and your own country’s legal process does not come into it.
That power is the reason both of these documents exist. One side says the switch was used well. The other says it was used slowly. Either way, it is a reminder that a balance in USDT is a claim on a company that can freeze it.
What each side published
The Senate report, Tethered to Terrorism: Crypto & Iran’s Shadow Banking Network, came from the Democratic minority staff of the Permanent Subcommittee on Investigations, under ranking member Richard Blumenthal. Staff took transaction data from 846 crypto wallets that had either been sanctioned by the US Treasury’s Office of Foreign Assets Control or targeted for seizure by Israel’s National Bureau for Counter Terror Financing over links to Iran and regional armed groups.
The report says roughly 84% of those wallets transacted exclusively or almost exclusively in USDT. Its own conclusion, in the report’s words, is that “the Subcommittee’s analysis demonstrates that USDT has become a significant financial lifeline within Iran’s shadow banking network.”
Blumenthal put it harder in his accompanying press statement, saying his report “exposes how Tether and its flagship token have become central to Iran’s shadow banking system, allowing the Iranian government to fund its regional proxies, commit human rights abuses, and pursue hostile drone and missile programs as they defy our sanctions regime.” He referred the findings to Treasury and Justice and asked both to examine the company’s sanctions and anti-money-laundering compliance.
Tether published its own release the same day. It says actions involving USDT led to approximately $550m being frozen across addresses US authorities connected to Iran’s central bank and to Iranian sanctions networks: more than $344m across two wallets in April, with OFAC adding those same addresses to its Central Bank of Iran entry the following day, and more than $130m across four TRON wallets in July. Chief executive Paolo Ardoino said in the release that “Tether has consistently demonstrated that USD₮ is not a haven for sanctioned actors, terrorist organizations or criminal networks.”
Two numbers that do not quite add up
The itemised freezes come to roughly $474m. The release does not break down how the remaining $75m or so of the headline total was frozen, and the figure is self-reported rather than audited. Tether also leads with a cumulative all-time number, more than $4.9bn frozen in cooperation with law enforcement globally and more than $2.4bn of that tied to US authorities, which is a wider claim than the Iran figures on their own support.
On the other side, a referral is a letter. It does not establish that Tether violated federal law, and neither department has confirmed a new case. The report is preliminary and comes from minority staff, so the Republican majority on the same subcommittee has not co-signed it.
The lag is the actual argument
Senate investigators describe a case where some addresses tied to a single designation were blacklisted while others were left alone for a period, during which more than $34.6m in USDT moved out of the unfrozen wallets. That detail comes from the report as described in secondary coverage, and the dates attached to it in some write-ups look garbled, so treat the timeline as unconfirmed.
What it shows, if the figure holds, is a gap between the moment a wallet was publicly flagged and the moment the issuer switched it off. That is a timing problem rather than evidence that the company was asked to act and declined. Tether’s framing is that it reacts to information from authorities: Ardoino’s statement says “public provide authorities with a level of visibility into the movement of funds that simply does not exist with cash, and Tether can act when credible information is provided by law enforcement.”
Worth being careful with the percentages too. The wallets in the sample were already flagged or designated, so 84% describes which currency sanctioned actors were using by the time they were caught. A separate figure reported elsewhere, 87% of 757 wallets, uses a different denominator again. Neither measures USDT’s overall share of Iran-linked illicit finance, and neither measures the company’s compliance record.
What it means from here
An issuer freeze is not a seizure. The tokens are not forfeited, not transferred to a government, and not returned to anyone. They sit where they are, unusable, until the issuer says otherwise.
For a UK holder that distinction matters more than the politics. UK sanctions run through OFSI and the Treasury’s consolidated list, and the EU has its own regime, but none of that governs whether Tether blacklists an address. The power sits in the token’s , so a US designation reaches a balance held in Manchester on exactly the same terms as one held in Miami. If you route money through USDT between trades, our guide to withdrawals covers what to do when funds stop moving, and self-custody explains where holding your own keys does and does not help. Holding your own keys does not help here: a frozen token is frozen in your wallet as readily as on an exchange.
What to watch
Whether Treasury or Justice confirms anything at all. A referral that produces no action in six months was a press release with a footnote. Whether any Republican member of the subcommittee signs up to the findings, which would turn minority staff work into a committee position. And whether Tether accounts for the unitemised $75m, because the company chose to publish a round total and only showed its working for most of it.