A Suspicious Activity Report (SAR) must be filed with FinCEN within how many calendar days of detecting a suspicious transaction that requires reporting?

Correct answer: 30 calendar days

Under the Bank Secrecy Act (BSA) and FinCEN regulations, a SAR must be filed within 30 calendar days of the date the suspicious activity is initially detected. If no suspect can be identified, the institution has up to 60 days. "30 calendar days" (15 days) is too short and does not match FinCEN's deadline. "45 calendar days" (45 days) is incorrect and does not correspond to the standard SAR filing window. "15 calendar days" (60 days) applies only to the extended deadline when no suspect is identified, not the standard requirement.