Portugal is a party to the Schengen Agreement. This means that U.S. citizens may enter Portugal for up to 90 days for tourist or business purposes without a visa. Your passport should be valid for at least six months. You need sufficient funds to support you during your stay and a return airline ticket. For additional details about travel into and within Schengen countries, please see our Schengen fact sheet.
If you transited through another Schengen country by air, sea or land en route to Portugal without having registered your entry and you are not staying in a hotel or a similar tourist accommodation, you are subject to the requirement to register with local immigration officials within three working days of entering Portugal. You must document your entry to prove your length of stay. Request a stamp at an official point of entry, or download a declaration of entry (declaracão de entrada) from the Portuguese Immigration Service’s (SEF) website, and personally submit it to the nearest SEF office within three business days of entry. You must also present your passport. Failure to comply with these requirements will result in an administrative offense punishable with a fine from €60 to €160.
Under Portuguese Immigration law, foreign minors under 18 years of age entering or exiting Portugal must be in possession of an authorization letter of parental consent to travel, if travelling with adults other than their parent/s or legal guardians. The document must be signed and dated, with the signature(s) certified by a notary. The letter of parental consent to travel must include the dates and reason for travel and the details of an adult who will be responsible for the child.