To declare goods at Portugal customs, identify if your items exceed duty-free limits or are restricted, use the red channel at entry points, submit a declaration form with supporting documents, pay any applicable duties, and be aware that penalties for non-compliance may. To declare goods at Portugal customs, identify if your items exceed duty-free limits or are restricted, use the red channel at entry points, submit a declaration form with supporting documents, pay any applicable duties, and be aware that penalties for non-compliance may. When entering or leaving Portugal, travellers must comply with customs rules and allowance limits. These rules determine what goods you may carry and which items must be declared or are subject to duties and taxes. Who has to go through. As a member of the European Union (EU), Portugal adheres to strict customs regulations when it comes to receiving packages from countries outside the EU. EU-UK TCA provides 0% on qualifying UK goods. All non-EU imports above €150 are subject to EU common. Baggage Certificate – This can be obtained at a Portuguese Embassy or Consulate of the country you are leaving. This document is very important as it will give you exemption of taxes and duties.