A Suspicious Activity Report (SAR) is a formal document submitted to a Financial Intelligence Unit (FIU) by financial institutions and other regulated entities when they detect activity that may be linked to Money Laundering, Terrorist Financing, Fraud or other forms of Financial Crime. The purpose of a SAR is to alert authorities to potentially suspicious transactions or behavior without notifying the customer involved.

Filing a SAR is a legal requirement under Anti-Money Laundering (AML) regulations in many jurisdictions. In the United States, for example, SARs are submitted to the Financial Crimes Enforcement Network (FinCEN) under the Bank Secrecy Act (BSA). Similar requirements exist globally, aligned with recommendations from the Financial Action Task Force (FATF).

A SAR typically includes detailed information about the parties involved in the activity, a description of the suspicious behavior or transaction, and the rationale for why it was deemed suspicious. Common triggers for a SAR include unusual transaction patterns, attempts to avoid reporting thresholds, inconsistent customer profiles or links to High Risk Jurisdictions or sanctioned individuals.