On arrival, Portugal applies Certificado de Bagagem (Portuguese consulate) under EU customs framework (jurisdiction-specific). Import VAT in Portugal is 23%, and relief is what keeps your household goods out of that charge. Shipments normally arrive through Lisbon or Leixões (Porto).
This page covers what actually changes on the United States → Portugal route: what you will pay, how long the shipment is at sea, the paperwork Portugal customs expects from a departure in United States, and what to do about pets, a vehicle and somewhere to live when you land.
Departures from United States normally load at New York / New Jersey, Savannah, Houston. Household goods leaving the US move under an ocean carrier booking filed with US Customs at least 24 hours before loading. Personal effects shipments are normally filed by your forwarder; you sign a power of attorney authorising them to act. Video or in-home surveys are widely available across the continental US; crews are typically scheduled 2–4 weeks ahead. The corridor covers roughly 3,980 nautical miles.