A Currency Transaction Report (CTR) and a Suspicious Activity Report (SAR) are the two main filings U.S. financial institutions send to the Treasury Department about customer transactions, and the difference between a SAR and a CTR comes down to this: a CTR is an automatic report triggered whenever more than $10,000 in physical cash moves through an account, while a SAR is a confidential, judgment-based report filed when a transaction looks like it could involve illegal activity, no matter the dollar amount. They go to the same agency. They follow different rules, run on different clocks, and have very different consequences for the person named in them.
What a CTR Is and When It’s Filed
A CTR is mechanical. If a deposit, withdrawal, exchange, or transfer involves more than $10,000 in physical currency, the institution must file one. No one at the bank is judging whether the transaction looks odd. The dollar amount alone triggers the filing.1eCFR. 31 CFR 1010.311 – Filing Obligations for Reports of Transactions in Currency
“Currency” means coins and paper bills. Checks, wire transfers, and electronic payments don’t count toward the threshold even when they’re far larger.
The threshold also catches cash spread across a single business day. Three separate $4,000 cash deposits at the same bank on Tuesday get aggregated into one $12,000 transaction, and a CTR is filed. Night-drop and weekend deposits are treated as received on the next business day.2FFIEC BSA/AML InfoBase. FFIEC BSA/AML Assessing Compliance with BSA Regulatory Requirements – Currency Transaction Reporting The aggregation applies whenever the bank knows the transactions were conducted by or on behalf of the same person. Multiple smaller trips don’t help.
To complete the CTR, the institution records the customer’s name, address, Social Security or taxpayer identification number, account number, and a verified government-issued ID such as a driver’s license. The specific ID number used for verification has to appear on the report itself.2FFIEC BSA/AML InfoBase. FFIEC BSA/AML Assessing Compliance with BSA Regulatory Requirements – Currency Transaction Reporting
What a SAR Is and When It’s Filed
SARs are the opposite of automatic. A bank files one when it knows, suspects, or has reason to suspect that a transaction involves illegal funds, is designed to evade federal reporting rules, or has no apparent lawful purpose given what the bank knows about the customer. For banks, the regulatory floor is $5,000. The transaction must involve or aggregate at least that much before the filing becomes mandatory.3eCFR. 31 CFR 1020.320 – Reports by Banks of Suspicious Transactions
Below $5,000, a bank can still file voluntarily if it believes the activity is relevant to a possible legal violation.4eCFR. 31 CFR 1020.320 – Reports by Banks of Suspicious Transactions Dollar amount does not shield a transaction from a SAR the way it governs a CTR.
The heart of a SAR is its narrative, where the institution explains in plain language exactly what raised red flags about the activity, including how the suspect moved or concealed funds.5Financial Crimes Enforcement Network. FinCEN SAR Narrative Completion Guidance A CTR has no narrative. It’s a form full of identifiers.
Can the Bank Tell You About It
This is the sharpest practical difference between the two reports, and the one that matters most to someone who shows up in them.
A CTR is a routine administrative filing, and the bank is allowed to tell you about it. Business owners who regularly deposit cash expect these filings and often hear about them at the teller window.
SARs operate under strict secrecy. Federal law prohibits a financial institution and all of its current or former employees from telling anyone that a SAR has been filed or that one even exists. Breaking that confidentiality can result in civil penalties of up to $100,000 per violation, criminal fines of up to $250,000, and imprisonment of up to five years. If the disclosure stems from broader anti-money-laundering program failures, additional penalties of up to $25,000 per day can stack on top.6Financial Crimes Enforcement Network. FinCEN Advisory FIN-2012-A002 – SAR Confidentiality Reminder
To keep the secrecy workable, federal law gives banks a safe harbor. Any institution or employee that files a SAR, or voluntarily discloses a possible violation, is shielded from civil liability. The person named in the report cannot sue the bank for filing it, regardless of whether the suspicion turns out to be wrong.7Office of the Law Revision Counsel. 31 USC 5318 – Compliance, Exemptions, and Summons Authority
If you ask your bank directly whether a SAR has been filed on you, they are legally required to refuse to answer. That isn’t evasion. It’s the law.
Filing Deadlines
CTRs are due within 15 calendar days of the transaction.8eCFR. 31 CFR 1010.306 – Filing of Reports The clock is simple because the trigger is a specific, dated cash transaction.
SAR deadlines run from a different starting point: the moment someone at the institution first notices something suspicious, not the date of the transaction itself. From that initial detection, the institution has 30 calendar days to file. If suspicious activity is detected but no suspect can be identified, the deadline extends to 60 calendar days.9FFIEC BSA/AML InfoBase. FFIEC BSA/AML Assessing Compliance with BSA Regulatory Requirements – Suspicious Activity Reporting
Both reports go through the BSA E-Filing System, a secure electronic portal run by the Financial Crimes Enforcement Network (FinCEN), a bureau of the Treasury Department.10Financial Crimes Enforcement Network. BSA E-Filing System Paper filings are no longer accepted.11Financial Crimes Enforcement Network. Bank Secrecy Act Filing Information Institutions must retain copies of SARs and their supporting documentation for five years from the filing date.12Financial Crimes Enforcement Network. Suspicious Activity Report Supporting Documentation The same five-year retention rule applies broadly to BSA records, CTR documentation included.13FFIEC BSA/AML InfoBase. FFIEC BSA/AML Appendices – Appendix P – BSA Record Retention Requirements
Structuring: Why Dodging a CTR Triggers a SAR
The two reports connect through one specific behavior: structuring. Structuring is the practice of deliberately breaking up cash transactions to stay below the $10,000 CTR threshold. Depositing $9,500 on Monday and $9,500 on Tuesday instead of $19,000 at once is the textbook example. Federal law makes this a standalone crime, even when the underlying money is completely legitimate.14Office of the Law Revision Counsel. 31 USC 5324 – Structuring Transactions to Evade Reporting Requirement Prohibited You don’t need to be laundering drug proceeds or evading taxes. Splitting transactions to dodge the reporting requirement is itself illegal.
Structuring is also one of the most common reasons banks file SARs. A teller trained in BSA compliance will flag repeated deposits just under $10,000. The result is almost backwards from what someone trying to avoid attention expects: a routine CTR is visible and harmless, while trying to avoid one generates a confidential SAR that draws far more scrutiny and that the customer cannot even be told about.
Penalties depend on scale. When the illegal conduct involves less than $100,000 within a 12-month period, a conviction can bring up to five years in federal prison and a fine of up to $250,000. If the structuring involves more than $100,000 in a 12-month period or is tied to another criminal offense, the maximum sentence doubles to 10 years, with fines up to $500,000.15Office of the Law Revision Counsel. 31 USC 5322 – Criminal Penalties Federal authorities can also seize structured funds, though Department of Justice policy generally requires evidence linking the money to criminal activity beyond the structuring itself before pursuing forfeiture.
Who Has to File These Reports
Banks and credit unions handle most CTR and SAR filings, but the Bank Secrecy Act defines “financial institution” more broadly than most people assume. The definition reaches brokers and securities dealers, money services businesses (which includes check cashers, currency exchanges, and money transmitters), and casinos or card clubs with more than $1 million in gross annual gaming revenue.16eCFR. 31 CFR 1010.100 – General Definitions Dealers in precious metals, stones, or jewels also fall under BSA obligations when transactions involve significant cash payments.
All of these entities file through the same BSA E-Filing System and face the same retention requirements. For a customer, that means moving large cash sums to a check casher, a casino cage, or a money transmitter does not escape the reporting regime. The same two reports, with the same rules about disclosure and the same confidentiality around SARs, apply there too.