Meet Anna, a teller at a small community bank in Ohio.
Most days, her work is routine: deposit slips, warm greetings, and the occasional small-town gossip about the football game. But one Tuesday, something unusual happens.
Mr. Clark, a quiet man who normally deposits his paycheck, walks in carrying a shoebox filled with cash. He asks Anna to split it into three different deposits—each just under $10,000.
Anna’s stomach tightens. She’s seen plenty of cash deposits before, but something about this doesn’t feel right.
And that gut feeling? It’s exactly where most Suspicious Activity Reports (SARs) begin.
Why SARs Exist
Before we dive into Anna’s steps, let’s zoom out for a second.
A Suspicious Activity Report (SAR) is a confidential filing that financial institutions must send to the Financial Crimes Enforcement Network (FinCEN) whenever they spot something unusual.
Think of it as your way of telling FinCEN:
“We saw something that doesn’t add up. You may want to look closer.”
You’re not accusing anyone of a crime—you’re flagging activity so investigators can connect the dots.
Red Flags Anna Noticed
Back to Anna. Why did the shoebox set off her internal alarm?
- Structuring: Multiple deposits just under $10,000 suggest an attempt to avoid the Currency Transaction Report (CTR).
- Behaviour Change: Mr. Clark’s history didn’t include large cash deposits. This was new.
- Unusual Source: A shoebox stuffed with cash isn’t exactly a standard way to handle legitimate earnings.
Compliance Tip: Always look for patterns and sudden changes. Risk often hides in behaviour that doesn’t fit the customer’s normal profile.
How to File a Suspicious Activity Report (SAR) in the U.S.
Here’s exactly what Anna did—and what you should too:
- Notice Something Off
Suspicion doesn’t require proof of crime. It requires a reasonable belief that the activity is unusual, inconsistent, or designed to hide something.
- Document Everything Internally
Anna didn’t rely on memory. She wrote down:
- Dates and times of deposits
- Exact amounts ($9,900 each)
- Mr. Clark’s instructions to split the money
- Notes on his behaviour and attitude
Pro tip: Detailed internal notes save time later and strengthen the SAR narrative.
- Escalate to the Compliance Officer
At most banks, tellers don’t file SARs directly. They escalate to a compliance officer (CO) or manager, who decides whether the activity meets the SAR threshold.
Anna followed her bank’s internal escalation policy.
- File Through FinCEN’s BSA E-Filing System
The CO logged into BSA E-Filing and completed SAR Form 111.
The form asked for:
- Who: Mr. Clark’s details, accounts, and ID.
- What: Description of the cash deposits and instructions.
- When/Where: Specific dates, amounts, and branch location.
- Why Suspicious: Explanation of structuring behaviour.
Golden Rule: Keep it factual. Avoid speculation, personal opinions, or accusations.
- Meet the Filing Deadline
- 30 days: If you can identify the suspect.
- 60 days: If you need more time to collect details.
Anna’s bank filed well within the 30-day window.
- Keep It Confidential
Here’s the tricky part: SARs are secret by law.
That means:
- Anna couldn’t tell Mr. Clark.
- She couldn’t warn other tellers.
- She couldn’t even tell friends or family.
Violation of SAR confidentiality carries serious penalties.
- Retain Records
Her bank stored a copy of the SAR and all supporting documents for five years, as required.
What Happens After Filing?
This is where many people wonder: “Does FinCEN investigate right away?”
Here’s the reality:
- SARs don’t usually trigger an immediate response.
- Instead, they go into FinCEN’s massive database.
- Law enforcement agencies access that database when building cases.
So, Anna may never hear what happened—but her SAR could be the missing puzzle piece in a much bigger investigation.
Real-World Impact of SARs
- Drug trafficking cases: SARs often uncover cash smuggling operations.
- Terrorism financing: Small, unusual transfers flagged by SARs have led to dismantling networks.
- Fraud rings: Patterns emerge when multiple banks file SARs on the same individuals.
Each SAR adds a breadcrumb for investigators to follow.
Quick SAR Filing Checklist
Watch for unusual or suspicious activity
Document facts clearly (dates, amounts, behaviour)
Escalate to your compliance officer
File electronically through FinCEN (Form 111)
Submit within 30 days (60 if extended)
Keep the report factual—no opinions
Never disclose the SAR to the customer
Retain SAR + supporting docs for 5 years
Small Action, Big Impact
It started with a shoebox of cash and a hunch. Filing that SAR might have felt like just another task for Anna, but in reality, her report could be part of something much larger.
When combined with thousands of other SARs, these small alerts help uncover criminal networks, disrupt money laundering schemes, and protect the integrity of the financial system.
That’s the real power of SARs: individual vigilance fuelling collective protection.
