5.4 IAT (International ACH Transactions): Mandatory Addenda & OFAC Screening

5.4 IAT (International ACH Transactions): Mandatory Addenda & OFAC Screening

Core Principle: An International ACH Transaction (IAT) is a Standard Entry Class code mandated for any ACH payment that involves a Financial Agency located outside the territorial jurisdiction of the United States. Designed to align the ACH Network with the Bank Secrecy Act (BSA), FinCEN Travel Rule (31 CFR Section 1010.410), and Office of Foreign Assets Control (OFAC) sanctions requirements, IAT enforces a rigid 7-addenda record payload and strict screening mandates.

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1. IAT Scope & Defining Criteria

The Definition of a Financial Agency

Under Nacha Operating Rules (Article Eight), a Financial Agency is defined broadly as an entity authorized by a foreign government to accept deposits, issue letters of credit, hold funds, or execute funds transfers—including foreign commercial banks, central banks, offshore branches of U.S. banks, money services businesses (MSBs), and licensed currency transmitters.

When Must a Transaction Be Classified as IAT?

A transaction MUST be originated using the IAT SEC code whenever:

1. Direct Cross-Border Flow: Funds move directly between a U.S. financial institution and a foreign financial agency.
2. Indirect / Intermediary Cross-Border Flow: A foreign financial agency acts as an intermediary, sender, instructing party, or ultimate beneficiary in the payment chain—even if the entry clears between two domestic U.S. bank accounts.

IAT IDENTIFICATION SCENARIOS

Scenario 1: Direct Inbound
[Foreign Employer Bank (London)] ===> [U.S. Gateway Operator] ===> [U.S. RDFI (Payroll Direct Deposit)]
=> MUST BE IAT

Scenario 2: Direct Outbound
[U.S. Corporate Originator] ===> [U.S. ODFI] ===> [U.S. Gateway Operator] ===> [Foreign Supplier Bank (Tokyo)]
=> MUST BE IAT

Scenario 3: Domestic Leg of Cross-Border Movement (Funded Transfer)
[Foreign Parent Co] --(Wire)--> [U.S. Account A] --(ACH Transfer)--> [U.S. Account B]
=> If U.S. ACH transfer is explicitly funded from foreign wire, it MUST BE IAT

Inbound vs. Outbound IAT

• Inbound IAT: Originates outside the U.S., enters the domestic ACH Network through a U.S. Gateway Operator (FedACH or EPN) acting as the ODFI, and is delivered to a domestic RDFI.
• Outbound IAT: Originates from a domestic U.S. Originator/ODFI, clears through a U.S. Gateway Operator, and is delivered to a foreign receiving gateway / foreign financial agency.

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2. Technical Blueprint: The Mandatory 7-Addenda Record Structure

Unlike domestic SEC codes that carry zero, one, or variable addenda records, every single IAT Entry Detail Record (Type 6) MUST be accompanied by a minimum of seven (7) mandatory Addenda Records (Type 7) in an unalterable sequential order (Addenda Type Codes 10 through 16).

THE IAT 7-MANDATORY ADDENDA STACK
+-----------------------------------------------------------------------------------------+
| Type 6: IAT Entry Detail Record (Addenda Indicator = '1')                               |
+-----------------------------------------------------------------------------------------+
  ├── Type 7: Addenda 10 -> Foreign Exchange Indicator, ISO Country Code, Currency Code    
  ├── Type 7: Addenda 11 -> Originator Name & Originator Street Address                    
  ├── Type 7: Addenda 12 -> Originator City, State/Province, Postal Code & Country Code     
  ├── Type 7: Addenda 13 -> Originating DFI / Foreign Financial Agency Name & Identifier   
  ├── Type 7: Addenda 14 -> Receiving DFI / Foreign Financial Agency Name & Identifier     
  ├── Type 7: Addenda 15 -> Receiver Name & Receiver Street Address                        
  └── Type 7: Addenda 16 -> Receiver City, State/Province, Postal Code & Country Code      
  -----------------------------------------------------------------------------------------
  (Additional Addenda Records Follow Below)
  ├── Type 7: Addenda 17 -> Remittance Information (ANSI ASC X12 / Invoice data, Max 2)   
  └── Type 7: Addenda 18 -> Foreign Correspondent Bank Information (Up to 5 when foreign correspondents are involved)                 

Field-by-Field Breakdown of IAT Addenda Records (10–18)

Foreign Exchange Rate Indicators in Addenda 10

• FV (Fixed-to-Variable): Entry originated in fixed U.S. Dollars; converts to a variable foreign currency amount at the receiving endpoint.
• FF (Fixed-to-Fixed): Entry originated in a fixed foreign currency and settles in the exact same fixed amount in foreign currency (or vice versa).
• VF (Variable-to-Fixed): Entry originated in variable U.S. Dollars calculated to yield a fixed target foreign currency payout.

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3. OFAC Sanctions Compliance & Screening Obligations

The Office of Foreign Assets Control (OFAC) of the U.S. Department of the Treasury administers and enforces economic and trade sanctions against targeted foreign countries, terrorists, international narcotics traffickers, and entities engaged in weapons proliferation.

                                  OFAC SANCTIONS SCREENING WORKFLOW
                               ┌────────────────────────────────────┐
                               │ Incoming IAT Entry (Addenda 10-16) │
                               └─────────────────┬──────────────────┘
                                                 │
                                                 ▼
                               ┌────────────────────────────────────┐
                               │ Screen all Parties against SDN List│
                               │ (Originator, Receiver, Banks)      │
                               └─────────────────┬──────────────────┘
                                                 │
                     ┌───────────────────────────┴───────────────────────────┐
                     ▼                                                       ▼
       ┌───────────────────────────┐                           ┌───────────────────────────┐
       │ NO MATCH / FALSE POSITIVE │                           │ TRUE MATCH (SDN HIT)      │
       │ Post / Transmit Entry     │                           │ Check Program Mandate     │
       └───────────────────────────┘                           └─────────────┬─────────────┘
                                                                             │
                                                 ┌───────────────────────────┴───────────────────────────┐
                                                 ▼                                                       ▼
                                   ┌───────────────────────────┐                           ┌───────────────────────────┐
                                   │ BLOCK / FREEZE FUNDS      │                           │ REJECT / PROHIBIT         │
                                   │ • Place in Blocked Acct   │                           │ • Return Entry via ACH    │
                                   │ • DO NOT RETURN via ACH   │                           │ • Return Code: R16        │
                                   │ • Report to OFAC in 10 d  │                           │ • Report to OFAC in 10 d  │
                                   └───────────────────────────┘                           └───────────────────────────┘

Screening Obligations by Participant

1. U.S. Gateway Operators: Must screen all inbound and outbound IAT entries passing through their central clearing facilities.
2. Originating DFIs (ODFIs): Must screen all outbound IAT entries, including Originator, Receiver, and all foreign financial agencies identified in Addenda 10–18, before releasing the file into the ACH Network.
3. Receiving DFIs (RDFIs): Must screen all inbound IAT entries against the Specially Designated Nationals and Blocked Persons (SDN) List prior to posting funds to customer accounts.

The Critical Distinction: Blocking vs. Rejecting

When an RDFI or Gateway Operator identifies a confirmed OFAC match, it must determine whether the specific sanctions program mandates Blocking (Freezing) or Rejecting:

• Blocking (Asset Freeze):
  • Required under comprehensive sanctions (e.g., targeted terrorist organizations, narcotics kingpins, specific sanctioned regimes).
  • Action: The RDFI must freeze the funds immediately and hold them in a segregated, interest-bearing blocked account.
  • STRICT PROHIBITION: The RDFI MUST NOT return the entry through the ACH Network! Returning a blocked entry releases the funds back into the financial stream, violating federal law.
  • Reporting: Must file a formal blocking report with OFAC within ten (10) business days.
• Rejecting (Transaction Prohibition):
  • Required when a transaction is prohibited by OFAC policy but no blockable property interest exists.
  • Action: Follow OFAC instructions. During the October 2026 exam window, use R16 when OFAC instructs the RDFI to return the Entry. R85 addresses an incorrect foreign-exchange indicator and is not a sanctions-return code.
  • Reporting: Must file a formal rejection report with OFAC within ten (10) business days.

Bank Secrecy Act / FinCEN Travel Rule (31 CFR Section 1010.410)

The IAT 7-addenda format satisfies the FinCEN Travel Rule mandate for funds transfers of $3,000 or more, ensuring that full originator name, street address, account number, identity of financial institutions, and beneficiary data travel with the payment order throughout the complete clearing chain.

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4. Exclusion from Same Day ACH

Under the Nacha Operating Rules in force for the October 2026 exam, IAT entries are excluded from Same Day ACH processing.

This is a Rules eligibility restriction, not a conclusion that IAT files are technologically impossible to process quickly. IAT screening, gateway, foreign-payment, and addenda obligations still apply, but the exam answer turns on the explicit Same Day eligibility rule.

$\text{Same Day ACH Eligibility} = \text{PPD, CCD, CTX, WEB, TEL} \quad \text{---} \quad \text{IAT (Strictly Excluded)}$

If an Originator attempts to transmit an IAT entry with a same-day Effective Entry Date, the ACH Operator automatically assigns the transaction to the next standard (next-day) clearing window.