Portugal IBAN Validator

Portuguese IBAN (PT): 25 characters with embedded NIB

A Portuguese IBAN is exactly 25 characters long and is one of the most structured in Europe because it embeds the legacy NIB (Numero de Identificacao Bancaria), the 21-digit domestic format that Portugal used before 2008. Today the NIB is essentially the BBAN portion of the IBAN, which is why every modern PT account can be expressed as either format depending on the channel.

The layout is: PT (country) + 2 check digits (mod-97-10) + 4 bank code + 4 branch code (balcao) + 11 account number + 2 internal NIB control digits. Example: PT50 0035 0000 0000 0000 0000 0.

Main Portuguese banks and codes

• 0010 Banco BPI
• 0033 Millennium BCP (largest private bank)
• 0035 Caixa Geral de Depositos (CGD, state-owned)
• 0036 Banco Santander Totta
• 0045 Caixa Central de Credito Agricola Mutuo
• 0046 Banco BIC Portugues (EuroBic)
• 0079 Caixa Economica Montepio Geral
• 0193 Banco BNI Europa
• 0269 Activobank (CGD digital arm)

Two-layer validation: IBAN mod-97 plus NIB internal check

A PT IBAN passes two arithmetic checks. The outer one is the standard ISO 7064 mod 97-10 shared by every IBAN in the world. The inner one is the NIB control digit, computed by Portuguese banks with a weighted sum on the first 19 digits modulo 97 — so a typo inside the account number can still be caught even when the IBAN-level math is satisfied.

// IBAN mod-97
move = PT50 ... -> ...PT50
letters -> digits (P=25, T=29)
n mod 97 == 1  -> valid IBAN
// NIB inner check (Portuguese-specific)
weights = [73, 17, 89, 38, 62, 45, 53, 15, 50, 5, 49, 34, 81, 76, 27, 90, 9, 30, 3]
sum(digit_i * weight_i) mod 97
control = 98 - sum mod 97

MB Multibanco, MB WAY and SEPA Direct Debit

Every PT IBAN plugs straight into the Multibanco network — the country's iconic ATM and POS system run by SIBS. MB WAY (Portugal's mobile payments app, similar to Pix or Bizum) sits on top of an IBAN: users link their phone number to the bank account and pay or split bills instantly. For recurring billing — utilities, gym, insurance — SEPA Direct Debit (SDD) with mandate is the default, again keyed by IBAN.

Comparison with Brazil: a Brazilian IBAN exists on paper (29 chars), but is virtually unused domestically — Pix dominates everything. In Portugal the opposite is true: the IBAN is the backbone of domestic and SEPA payments, and you cannot open a salary account without one.

Fintechs and challenger banks in Portugal

Challenger players issuing PT IBANs include Activobank (CGD), Moey! (Credito Agricola), BIG (Banco de Investimento Global), plus EU passporting banks like Revolut (Lithuanian IBAN LT mostly, but PT issuance since 2022), N26 (DE/ES IBAN) and Wise (BE IBAN). Brazilian residents with NIF can open Portuguese accounts to receive salaries, rent or D7/D8 visa proof-of-income.

FAQ

Is the IBAN mandatory for Portuguese domestic transfers? Yes. Since SEPA migration in 2014, every domestic transfer — Multibanco, MB WAY, online banking, salary — uses IBAN. The pre-2008 21-digit NIB is still recognised in some forms but always converted to IBAN at the rails level.

Does MB WAY use the IBAN behind the scenes? Yes. MB WAY is a UX layer on top of SIBS rails; the underlying transfer is settled to the IBAN linked to the registered phone number. Each MB WAY user maps one phone to one IBAN.

Can a Brazilian open a PT account remotely? Yes, with a Portuguese NIF (taxpayer ID) and acceptable ID documents. Banks like Activobank, Millennium and BPI offer remote onboarding for non-residents, and challenger banks such as Bnext or Wise issue EU IBANs without NIF residency requirement.

Why two check digits inside the NIB? Portuguese banks adopted the weighted mod-97 NIB scheme in the 1990s, before SEPA. When IBAN was added on top, the two control digits stayed embedded so that legacy back-office systems could keep validating accounts without parsing the IBAN.

Is a PT IBAN valid in Madeira and Azores? Yes. Madeira and Acores are part of Portugal and share the same PT country code and IBAN format — there is no separate registry.