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R04

ACH Return Code R04: Invalid Account Number Structure

Invalid Account Number

ACH Return Code R04 indicates that the account number structure is invalid according to the receiving bank's requirements.

What causes R04?

The R04 return code occurs when:
- The account number format is incorrect
- The account number contains invalid characters
- The account number length doesn't match bank requirements

How to resolve R04

  1. . **Verify account number format** - Ensure it meets banking standards
  2. . **Contact the customer** - Request the correct account number
  3. . **Implement validation** - Add format checking before submission

Prevention tips

  • Validate account number format before processing
  • Use bank-specific validation rules
  • Implement real-time account verification

How to resolve this return code

Follow these steps to address and prevent this ACH return.

1

Review the return code.

Identify the specific reason for the return and understand what information needs to be corrected.

2

Contact the customer.

Reach out to verify or update their banking information, especially for insufficient funds or invalid account issues.

3

Retry or adjust the payment.

Once corrected, resubmit the transaction or choose an alternative payment method.

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Slash provides real-time account validation, intelligent retry logic, and comprehensive analytics to help you minimize ACH returns and optimize your payment operations.

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