Mixer in an AML report

What it means

A mixer (or tumbler) takes coins from many users, pools them and pays out different coins, so the trail between where money came from and where it went is hard to follow. Some are custodial services; others are smart contracts.

Why it is a risk for you as the recipient

People use mixers for privacy, but they are also a standard step in laundering stolen and ransomware funds. Because the origin becomes unclear, exchanges often treat mixer exposure as high risk and ask for an explanation.

• When OFAC sanctioned the mixer Tornado Cash on 8 August 2022, it said the service had been used to launder more than USD 7 billion since 2019.^[1]
• On 21 March 2025 the US Treasury removed Tornado Cash from the SDN list, while saying it remained concerned about North Korean hackers laundering funds.^[2]

Example situation

Illustrative scenario, not a real case. An address offers you a good OTC rate for BTC. A check shows that 40% of its incoming coins came out of a mixer two hops earlier. You do not know who sent them into the mixer — and neither will your exchange.

What to do if it shows up in a report

1. Ask the counterparty where the coins came from and decide whether the explanation is credible.
2. Prefer to decline: you carry the risk if the exchange holds the deposit.
3. If you used a mixer yourself for privacy, keep records of the coins you put in and their origin.