Many countries require six months' validity beyond your arrival or departure date; the Schengen area requires three months beyond your planned exit and a passport issued within the last ten years. Airlines enforce these rules at check-in.
Six-month rule: common across Asia (Thailand, Indonesia, Vietnam, Singapore, China), the Middle East and much of Latin America and Africa. Some count from arrival, some from departure.
Schengen (EU/EEA): at least three months’ validity beyond your intended departure from the Schengen area, and the passport must have been issued within the previous ten years. The UK simply requires validity for your stay.
US: passports must be valid for the stay; some nationalities have six-month agreements. Visa-exempt visitors need an ESTA.
Check: IATA’s Timatic (via most airline sites) or the destination’s embassy page. Renew early — passport processing backlogs are common before summer.
Related questions
Do I need a visa to transit through an airport?
Depends on the country and your passport. Many hubs allow airside transit without a visa; the US, Canada and Australia require an ESTA/eTA/ETA even to transit; the UK requires a transit visa for some nationalities. Check before you book a connection. Full answer →
Is travel insurance worth it?
For international trips, medical cover alone justifies it — a hospital stay abroad can cost tens of thousands. Trip-cancellation cover is worth it for expensive, non-refundable trips. Check what your credit card already includes before buying. Full answer →
Airline, airport and government rules change without notice. Treat this as a starting point and confirm with the airline or authority for your specific trip. Request a correction if something is out of date.