Double Taxation Relief Manual: Guidance by country: Portugal: Relief from Portuguese tax
The Portuguese forms that are to be used to claim an exemption from, or a reduction in, Portuguese taxation under the United Kingdom/Portugal tax agreement may be obtained from the Portuguese tax authorities - Direccao-Geral das Contribuicoes e Impostos (Servico de Relacoes Fiscais Internacionais), Rua de Alfandega, Lisbon 2, Portugal or downloaded from the website of the Portuguese tax authorities, http://info.portaldasfinancas.gov.pt.
Photocopies are not accepted by the Portuguese authorities.
Certified forms for claiming an exemption from, or a reduction in, withholding tax need to be presented to the payer of the income before the date on which the withheld tax must be paid to the Portuguese tax authorities, i.e. the 20t h of the month following that in which the withholding tax liability arises. Claims need to be certified. The forms are bi-lingual and should be completed in triplicate by the claimant and sent, with the certificate of payment of Portuguese tax where appropriate, to the claimant’s tax office. If the necessary conditions are satisfied (see INTM162030),HMRC will complete and date stamp the declaration on all three copies, retaining one copy and returning the other two to the claimant.