If a company not established in Portugal is providing ‘taxable supplies’ digital services in Portugal, it may have to obtain a non-resident VAT registration with AT – autoridade tributaria e aduaneira.
A business established in a country outside the EU must appoint a tax representative to register for VAT in Portugal
The MOSS is also available. The Mini One Stop Shop (MOSS) is a special scheme that aims to facilitate the compliance of all obligations relating to telecommunications services, broadcasting and television and electronically supplied services to non-taxable persons in the EU in which they do not have an establishment to account for the VAT. If the supplier is established outside the European Union and does not have a fixed establishment in Portugal (nor in any Member State), and is not registered nor is legally required to register for VAT purposes in any Member State, it may choose Portugal as the Member State of Identification for MOSS purposes.