What is a fiscal representative and do I need one?

Short answer: A Portuguese-resident person or company that receives AT (Autoridade Tributária) correspondence on your behalf. Required while you are non-resident.

Article 19 CIRS requires non-EU non-residents holding a Portuguese NIF to appoint a fiscal representative. Greenlight Lda. can act as your representative — included with our NIF service. Once you move and become tax-resident, you can cancel the representation.