Federal law treats splitting a large cash deposit into smaller chunks under $10,000 to avoid bank reporting as a crime that can send someone to prison for up to 5 years, even when every dollar is legally earned. That penalty appears in 31 U.S.C. § 5324, which prohibits structuring transactions to dodge Bank Secrecy Act reports. The stakes are not abstract: regulators have highlighted a case where a defendant was convicted of structuring even though prosecutors did not allege money laundering or any other underlying crime.
Why breaking deposits into chunks matters now
The core rule comes from 31 U.S.C. § 5324, which bans anyone from structuring, attempting to structure, or helping structure transactions to evade currency reporting requirements, according to the statutory text published by the Office of the Law Revision Counsel at 31 U.S.C. § 5324. That provision sets a baseline maximum penalty that is commonly 5 years in prison for a violation. In practice, this means the government can charge a felony based solely on how a person arranges deposits or withdrawals, even if the source of the cash is lawful.
Regulators describe structuring as “breaking up” transactions to avoid the reports banks must file under the Bank Secrecy Act. The Financial Crimes Enforcement Network, or FinCEN, states that structuring occurs when someone conducts financial activity “in a particular way” to evade Bank Secrecy Act reporting or recordkeeping rules, including splitting cash into amounts under $10,000, according to its suspicious activity reporting guidance. FinCEN adds that multiple deposits below $10,000 across different days can still count as structuring if the pattern is meant to avoid a report.
The tension behind the headline is that enforcement targets behavior that can look like ordinary cash management. The Supreme Court in Ratzlaf v. United States, 510 U.S. 135, recognized that “currency structuring is not inevitably nefarious” and focused on the willfulness requirement for a conviction, according to the opinion text reproduced by Cornell Law School at 510 U.S. 135. Yet the statute still allows prosecutors to pursue prison time based purely on the pattern of transactions.
The evidence behind structuring prosecutions on clean money
FinCEN has documented a case that matches the headline’s warning. In a case example titled “Judge Rules Defendant Guilty of Structuring; No Connection to Criminal Activity Alleged,” the regulator reports that a defendant was convicted of structuring even though prosecutors did not bring money laundering charges because there was no indication the currency came from illegal activity, according to the narrative posted by FinCEN at its case examples page. The account states that the judge still found the defendant guilty of violating the structuring statute.
FinCEN’s guidance gives a concrete picture of how that can happen. The agency explains that a customer who makes several cash deposits below $10,000 on different days can still trigger a suspicious activity report if the pattern appears designed to avoid a currency transaction report, according to the same FinCEN guidance on suspicious activity reporting. FinCEN links that pattern directly to the definition of structuring under the Bank Secrecy Act.
On the reporting side, the Internal Revenue Service tells businesses that willful failure to report cash payments of more than $10,000 can lead to up to 5 years in prison, according to IRS Publication 1544 on reporting cash payments over $10,000. That publication describes structuring in plain language and connects it to Form 8300 obligations, reinforcing that the same 5 year ceiling appears in the cash reporting context.
The Department of Justice’s Criminal Resource Manual section on structuring explains that Congress enacted § 5324 to close gaps in the Bank Secrecy Act that had allowed people to avoid reporting simply by splitting transactions, according to the DOJ analysis at its structuring guidance. The manual highlights Ratzlaf v. United States, 510 U.S. 135, as a key Supreme Court decision on what the government must prove about a defendant’s intent.
Separate forfeiture rules add another layer. Under 31 U.S.C. § 5317, the government must show probable cause that funds were derived from an illegal source or structured to conceal another crime before the IRS can seize property in a structuring case, according to the statutory text at 31 U.S.C. § 5317. The Department of Justice has also announced that the Attorney General restricted the use of civil and criminal forfeiture for structuring offenses, generally requiring additional criminal activity or charges, according to a policy statement at a DOJ press release.
Bank reporting rules interact closely with these criminal statutes. Under 31 C.F.R. § 1010.313, a financial institution must aggregate multiple currency transactions that exceed $10,000 in one business day when it has knowledge of them, according to the regulation text at 31 C.F.R. § 1010.313. That aggregation rule explains why a person who tries to stay under $10,000 per visit can still trigger a single report and, if intent is proven, a structuring charge.
What remains unresolved and what to watch next
The central unresolved question is how often prosecutors now bring standalone structuring cases involving lawful funds after policy changes on forfeiture. The hypothesis that filings under 31 U.S.C. § 5324 declined in districts that adopted the 2015 restrictions while Bank Secrecy Act referrals stayed flat cannot be confirmed from the available primary sources. None of the cited statutes, guidance documents, or case examples provide district level filing statistics or trend data on referrals.
There is also limited public detail on how banks apply aggregation rules in practice beyond what 31 C.F.R. § 1010.313 requires and what FinCEN’s administrative rulings describe. The latest publicly available guidance in the record explains that multiple deposits under $10,000 across days can be viewed as structuring, but it does not quantify how often that pattern leads to criminal charges versus internal bank monitoring.
For readers who handle significant cash, the practical takeaway is straightforward. Federal law treats structuring as a separate offense, with a maximum 5 year prison term under § 5324 and a similar ceiling for willful reporting failures under IRS Publication 1544, even when the underlying money is legal. Anyone facing questions about repeated sub $10,000 deposits, Form 8300 obligations, or asset seizures is dealing with a system where the pattern of transactions, not just their source, can drive criminal exposure.
