Category: Suspicious Activity Reporting

Monetary Instrument Log

Also known as: MIL, Monetary Instrument Sales Log, MIL

Simply put

A Monetary Instrument Log is a record that certain financial institutions in the United States keep when they sell certain paper payment instruments (such as cashier's checks, money orders, and traveler's checks) for cash within a specified dollar range. It captures details about the purchaser and the transaction so the information can be retrieved later if regulators or law enforcement request it. Keeping the log is a recordkeeping duty, not the filing of a report, and the log's existence does not by itself indicate any wrongdoing.

Formal definition

In the US, the Monetary Instrument Log is the record maintained by banks and other affected financial institutions to satisfy the recordkeeping requirement associated with the sale of certain monetary instruments for cash, generally understood to fall under 31 CFR 1010.415. The obligation applies to the issuance or sale of bank checks and drafts, cashier's checks, money orders, and traveler's checks purchased with currency, and typically attaches when the currency used falls within a specified range (commonly cited as $3,000 to $10,000 in currency; the exact threshold values should be confirmed against the applicable regulation). This is narrower than the broader Bank Secrecy Act definition of "monetary instrument" at 31 CFR 1010.100, which also encompasses currency and other negotiable instruments such as personal and business checks, these latter items are not the instruments that trigger the MIL recordkeeping duty. Institutions must verify the purchaser's identity and retain the required transaction and purchaser information; per FFIEC BSA/AML guidance, such records must generally be retained for five years and made available to the Secretary of the Treasury upon request. The MIL is a compliance recordkeeping control and, unlike a Suspicious Activity Report, is not itself a report to FinCEN, and its entries do not establish criminal conduct.

Why it matters

The Monetary Instrument Log addresses a specific vulnerability in the payment system: paper instruments such as cashier's checks, money orders, and traveler's checks purchased with currency can be used to convert cash into more portable and transferable forms of value. By requiring covered institutions to capture purchaser and transaction details when these instruments are sold for cash within the applicable currency range (commonly cited as $3,000 to $10,000, with exact values to be confirmed against 31 CFR 1010.415), the MIL creates a retrievable audit trail that regulators and law enforcement can request later. This helps deter and detect the misuse of monetary instruments without imposing the burden of a filed report on every qualifying sale.

It is important to understand what the MIL is and is not. It is a recordkeeping control under the Bank Secrecy Act, not a report submitted to FinCEN, and it is fundamentally different from a Suspicious Activity Report. The existence of a log entry does not indicate suspicion, wrongdoing, or criminal conduct on the part of the purchaser; it simply reflects that a covered transaction occurred and was documented as the regulation requires. Compliance officers should be careful not to conflate a routine recordkeeping obligation with the separate, judgment-based decision to file a SAR.

Because the requirement is narrow in scope, precision matters for compliance staff calibrating their controls. The MIL duty attaches only to the specified instruments purchased with currency in the relevant range, it does not extend to every item that meets the broader BSA definition of "monetary instrument" at 31 CFR 1010.100, which also encompasses currency and negotiable instruments such as personal and business checks. Treating those broader items as MIL-triggering, or failing to capture qualifying cash sales, can each produce compliance gaps that examiners may identify during a BSA/AML review.

Who it's relevant to

BSA/AML compliance officers at US financial institutions

Compliance staff at banks and other affected US financial institutions are responsible for ensuring the MIL is maintained accurately for qualifying cash purchases of covered instruments. They must correctly scope the obligation to the specific instruments and currency range set out in 31 CFR 1010.415, ensure identity verification procedures are followed for both customers and non-customers, and confirm records are retained for the required five-year period.

Frontline tellers and branch staff

Employees who sell cashier's checks, money orders, and traveler's checks are the point at which MIL data is captured. They need clear procedures for recognizing when a purchase with currency falls within the threshold range and for collecting and verifying the required purchaser information at the time of sale.

BSA/AML examiners and auditors

Examiners assessing compliance with BSA regulatory requirements review whether covered institutions maintain complete and accurate monetary instrument sales records, retain them for the required period, and can make them available to the Secretary of the Treasury upon request. Internal auditors perform similar checks to identify recordkeeping gaps before an examination.

Law enforcement and financial intelligence analysts

Investigators may request MIL records to reconstruct how currency was converted into monetary instruments as part of a broader inquiry. Analysts should treat these records as an evidentiary trail to be corroborated, recognizing that a log entry documents a transaction and does not itself establish criminal conduct.

Inside MIL

Regulatory Basis and Nature

The Monetary Instrument Log (MIL) is a record-keeping requirement under the US Bank Secrecy Act, implemented at 31 CFR 1010.415. It is an operational recordkeeping obligation, not a reporting obligation, no filing is submitted to FinCEN as a consequence of maintaining the log itself, which distinguishes it from SAR or CTR reporting.

Covered Instruments

The recordkeeping duty applies to sales of bank checks or drafts, cashier's checks, money orders, and traveler's checks. It does not extend to personal checks or business checks. While 'currency' falls within the broader BSA definition of a monetary instrument at 31 CFR 1010.100(dd), currency itself is not one of the instruments for which a MIL must be kept.

Triggering Threshold

The obligation is triggered when a financial institution sells one or more of the covered instruments to a customer for currency in an aggregate amount between $3,000 and $10,000, inclusive. Sales in this currency range trigger the recordkeeping requirement; practitioners should confirm the exact triggering conditions against the current text of 31 CFR 1010.415.

Purchaser Information Captured

For each covered transaction, the institution generally records identifying details of the purchaser, distinguishing between purchasers who are deposit accountholders and those who are not, along with verification of identity information as specified in the regulation.

Transaction Details Captured

The log generally records the type(s) of instrument(s) purchased, the date of the transaction, the serial number(s) of the instrument(s), and the dollar amount(s) involved, so that transactions within the covered currency range are documented consistently.

Common questions

Answers to the questions practitioners most commonly ask about MIL.

Is maintaining a Monetary Instrument Log a suspicious activity reporting obligation?

No. The Monetary Instrument Log (MIL) requirement under 31 CFR 1010.415 is a record-keeping obligation, not a reporting obligation. It requires certain financial institutions to create and retain records when a customer purchases covered monetary instruments with currency, but it does not itself involve filing anything with FinCEN. It should not be confused with Suspicious Activity Reports (SARs), which are separate reporting obligations triggered by suspicion of unlawful activity, or with Currency Transaction Reports (CTRs). Retaining a MIL record does not indicate that a transaction is suspicious, and a purchase captured in the log does not establish any wrongdoing.

Does the Monetary Instrument Log cover personal checks, business checks, and currency itself?

No. While the broader Bank Secrecy Act definition of 'monetary instrument' at 31 CFR 1010.100(dd) is wider and includes currency, the MIL record-keeping duty under 31 CFR 1010.415 applies only to specific instruments purchased with currency: bank checks or drafts, cashier's checks, money orders, and traveler's checks. Personal checks and business checks are not covered by the MIL requirement, and currency itself, although part of the general BSA definition, is not one of the instruments for which a MIL record must be kept.

What currency amount triggers the requirement to make a Monetary Instrument Log entry?

Under 31 CFR 1010.415, the record-keeping duty generally applies when a customer uses currency in an amount between $3,000 and $10,000 inclusive to purchase one or more of the covered instruments (bank checks or drafts, cashier's checks, money orders, and traveler's checks). Transactions in currency above $10,000 may implicate separate reporting requirements such as the Currency Transaction Report. Because thresholds and their application can be affected by amendments and by aggregation rules, exact values and their treatment should be confirmed against the current text of the regulation and applicable FinCEN guidance.

What information does a Monetary Instrument Log entry typically need to capture?

The regulation generally requires the institution to record identifying information about the purchaser and details of the transaction, and the specific data elements differ depending on whether the purchaser is an established deposit accountholder or a non-accountholder. Institutions should map their MIL fields directly to the elements enumerated in 31 CFR 1010.415 and verify the current requirements, as the precise items to be recorded and the verification steps for accountholders versus non-accountholders are specified in the rule.

How long must Monetary Instrument Log records be retained?

MIL records are subject to the BSA record-retention framework applicable to required records. Institutions should confirm the applicable retention period against the current regulation and their own records-retention policy rather than assuming a period, and should ensure the records remain retrievable and available to examiners and, where applicable, to law enforcement upon appropriate request.

Which institutions are subject to the Monetary Instrument Log requirement, and how does it fit within an AML program?

The requirement applies to the financial institutions within the scope of 31 CFR 1010.415 that sell the covered instruments for currency; institutions should confirm their status as an obliged entity under the applicable BSA rules. Operationally, the MIL is one record-keeping control among others and functions to support detection, oversight, and law enforcement access; it is not, on its own, a measure that detects or prevents money laundering, and it does not replace customer due diligence, transaction monitoring, or suspicious activity reporting processes.

Common misconceptions

The Monetary Instrument Log is a type of report filed with FinCEN, similar to a SAR or CTR.

The MIL is a record-keeping requirement under 31 CFR 1010.415, not a reporting obligation. The institution creates and retains the log; it does not submit it as a routine filing. It should not be conflated with SAR or CTR reporting, which are distinct obligations under separate provisions.

The MIL requirement covers all monetary instruments, including personal checks, business checks, and currency.

Section 1010.415 applies only to bank checks or drafts, cashier's checks, money orders, and traveler's checks. Personal and business checks are outside its scope, and currency, though part of the broader BSA definition of monetary instrument at 31 CFR 1010.100(dd), is not an instrument for which the MIL must be maintained.

A recorded transaction in the MIL indicates suspicious or criminal activity.

The MIL captures qualifying instrument sales made for currency within a defined range regardless of any indication of wrongdoing. An entry in the log is a compliance record and does not, by itself, establish suspicion or any criminal-law conclusion; separate suspicious activity analysis and, where warranted, SAR filing follow their own standards.

Best practices

Configure point-of-sale and teller systems to identify covered instrument sales made for currency in the $3,000-$10,000 aggregate range so the recordkeeping trigger is captured consistently, and confirm the applicable threshold against the current text of 31 CFR 1010.415.

Restrict the log's scope to the instruments actually covered, bank checks or drafts, cashier's checks, money orders, and traveler's checks, and avoid inadvertently logging personal checks, business checks, or currency transactions as if they fell under this requirement.

Distinguish in your procedures between purchasers who are deposit accountholders and those who are not, since the information capture and verification steps generally differ between these categories.

Treat the MIL as a record-keeping control distinct from CTR and SAR obligations, and train staff not to assume that a log entry substitutes for, or triggers, any reporting requirement.

Retain MIL records for the period required under the BSA recordkeeping rules and confirm the exact retention period against the applicable regulation, ensuring records remain retrievable for examination.

Periodically test and reconcile the log against underlying transaction data to detect gaps, aggregation errors, or missed qualifying sales, treating this as a measure to manage compliance risk rather than a guarantee of complete capture.