Bank Secrecy Act.

In plain English

The Bank Secrecy Act, passed in 1970, is the backbone of US anti-money-laundering rules. It requires banks and other financial firms to keep records and file reports that help the government spot illegal money movement, such as reports on cash transactions above a threshold and on activity that looks suspicious. It is why a bank may ask about the source of a large deposit. The law is about detecting crime, not restricting ordinary customers, though it shapes a lot of what banks must track behind the scenes.

01Why it matters

The Bank Secrecy Act is the reason your bank asks questions about large cash deposits and monitors accounts, so it explains routine friction that is really about anti-crime rules.

02The math, step by step

You deposit 15,000 dollars in cash. Under Bank Secrecy Act rules, the bank files a currency transaction report with the government, a routine step for large cash amounts, not an accusation.

03What this is NOT