Portal das Finanças

Portal das Finanças (portaldasfinancas.gov.pt) is the official AT online portal where individuals and businesses manage their tax affairs. Key functions include: filing Modelo 3 (annual IRS return), viewing pre-filled automatic declarations, checking withholding tax tables, managing NIF registration and address, applying for special regimes (IFICI, IRS Jovem), downloading tax certificates and receipts, viewing payment history and outstanding tax debts, and accessing Documento Único Automóvel (vehicle tax) and VAT services. Access requires a NIF and password (or authentication key). Non-Portuguese speakers often find the portal challenging — an English interface is available for some sections, and many functions can be delegated to a certified accountant (TOC).