Error Code U03

U03 - Invalid IBAN Format

Learn what causes a U03 rejection for invalid IBAN formatting and how to repair the account details before resubmission.

Why this rejection happened

The payment was blocked because the destination account identifier failed structural validation, often due to an invalid checksum, country-specific length, or malformed IBAN characters.

How to fix it

Verify the country code and checksum of the IBAN in field 59. In MX (pacs.008), this must be strictly formatted under the CreditorAccount <Id><IBAN> element.

Common trigger points

IBAN formatting error
Destination account reject
Creditor account mismatch

Resolve U03 issues fast

Use the live SwiftMX Bridge converter to transform your MT instruction into a compliant MX payload and fix the underlying U03 problem before it blocks settlement.

Fix the account details in the converter