Circular Letter No. CC/2025/00000009: Rules for the Use of the Unique Identifier for Payment Accounts Domiciled with Payment Service Providers Established in Portugal (IBAN PT)

Circular Letter No. CC/2025/00000009
Sent to:
Credit Institutions, Financial Companies, Payment Institutions, and Electronic Money Institutions.
Mod. 99999924/T – 01/14
Subject: Rules for the use of the unique identifier of payment accounts domiciled with payment service providers established in Portugal (“IBAN PT”)

1. Background
   The International Bank Account Number (IBAN) is a standardized payment account number structure, established as an international standard in 1997 with the publication of ISO 13616 by the International Organization for Standardization (ISO). The IBAN is constructed from the BBAN (Basic Bank Account Number) adopted in each country, preceded by the respective country code and two control digits. In the particular case of payment accounts domiciled in Portugal, the IBAN is composed of the former NIB (Bank Identification Number), which corresponds to the Portuguese BBAN, preceded by the country code “PT” and two control digits, which, in the Portuguese case, are always “50”. With the publication of Regulation (EU) No 260/2012 of the European Parliament and of the Council of 14 March 2012 establishing technical and business requirements for credit transfers and direct debits in euros (SEPA Regulation), the IBAN became enshrined, for the purpose of executing direct debits and SEPA transfers, as the identifier of payment accounts opened with a Payment Service Provider (PSP) established in the European Union. In this context, the identification of national payment accounts and the correct routing of transfers and direct debits depends on the definition of the national BBAN and, consequently, on the IBAN of which it is an integral part.