Lisbon to Houston (LIS–IAH) — Airlines, Schedules & Connections

Portugal is part of the US Visa Waiver Program. Portuguese passport holders enter the United States for up to 90 days without a visa, but must obtain an approved ESTA (Electronic System for Travel Authorization) before boarding. The ESTA costs USD 21, is valid for 2 years or until the passport expires, and covers multiple entries. Apply at the official CBP site (esta.cbp.dhs.gov) at least 72 hours before departure.

The 90-day stay cannot be extended, and you cannot change immigration status while in the US on the Visa Waiver Program.

Metro Red Line runs from downtown Lisbon (Alameda, Oriente) to the airport in 20–25 minutes (€1.85 single, or €0.48 on a Viva Viagem card). Trains run from 6:30am to 1am. The airport has its own station (Aeroporto) at the end of the Red Line.

Taxis from central Lisbon cost €10–15 and take 15–20 minutes with no traffic. Uber and Bolt are widely available at similar or lower prices. AeroBus (Carris) is slower (30–40 min) but cheaper at €4.

No direct rail from IAH. The METRO bus 102 (IAH Express) runs to downtown Houston's transit center (60–90 min, $1.25). Taxis to downtown Houston cost $50–70. Ride-hails pick up at the designated Rideshare zones outside baggage claim on the lower level.IAH has five terminals (A–E) connected by an underground tunnel with trams. Terminal D handles international arrivals. Rental car agencies are in a consolidated facility adjacent to Terminal C; a free IAH Connector bus runs between terminals and the rental car center. The Galleria / Uptown area costs $35–50 by ride-hail.

Humid subtropical climate. Hot, humid, and wet for much of the year. Summers are brutal (33–38°C) with high humidity and near-daily afternoon thunderstorms. Severe storms with hail and high winds regularly cause ground stops from April through September. Houston's flooding risk is significant. Heavy rain events, including tropical system remnants, have flooded airport roads, cutting off surface access even when the airport itself remains operational.

Winters are mild (5–18°C) with occasional ice storms. These are rare but highly disruptive when they occur. Hurricane season (June–November) requires monitoring for Gulf storms. October through March has the best flying weather.