The basic structure of an international flight check in works the same as a domestic flight: You present yourself and any luggage, along with your ID and boarding pass, and go through a few security checkpoints on your way to the plane. But there are a few key differences you should be aware of: You’ll need to show up a little earlier; a passport is the only valid identification for international flights; for some countries you might need a visa; and on some U.S.-bound international flights, you’ll clear customs and immigration before getting on the plane instead of after arriving at your destination.

When to Arrive at the Airport

As a general rule, most airlines recommend arriving at the airport at least two hours before departure for domestic flights and at least three hours before departure for international flights. And, for domestic flights, you should add a little extra time if you’re traveling during peak periods when lines for security and at the ticket counter are likely to be long.

When you’re calculating how early to get in that security line, it helps to know a few standard benchmarks. Although there’s a lot of variance because of individual airport policies and screening policies for certain destinations, as a general rule, you’ll be safe if you are checked in (along with any checked baggage) at least 90 minutes before your flight, and if you’re at the gate, ready to board, by 45 to 60 minutes before departure time.


Always check with your airline before planning your timing for arrival at the airport. Airlines may impose special check-in requirements to specific international destinations, requiring you to check in several hours in advance and be at the boarding gate earlier than usual. There are a few particularly unusual cases, too. For example, if you're flying direct from Los Angeles to Cuba, you won't check in at the international terminal, and you'll need to pay for a Cuban tourist card – basically, a low-key visa – at the departure gate.

Documentation Required for International Travel

If you’re traveling to or from the United States by air, you need a valid passport to board your plane and enter the destination country. But it’s not enough for your passport to be valid at the time of entry; many countries require that your passport be valid for 30 days – or longer – past the planned end of your trip. Even if you’re traveling to a country that doesn’t impose this requirement, it’s still a good idea, because it ensures that you’ll have legal identification even if you become embroiled in a rare, but serious, travel snafu.

As for a domestic flight, you’ll need to show your passport and boarding pass as you go through the security screening, and you’ll be asked to show your passport when you go through customs and immigration, as well. At the boarding gate, you’ll be asked to show your passport and boarding pass again.


If you're a legal permanent resident of the United States, also known as a green card holder, you'll need to present your permanent resident card to re-enter the United States. But you'll also need a passport from your country of citizenship or, failing that, a refugee travel document, in order to enter destination countries outside the United States.

International Travel With Children

If you’re traveling with children, even infants, they’ll need a passport too. And if the kids you’re traveling with aren’t yours, or if they are yours, but both parents aren’t traveling together, be prepared to present letters of authorization from the absent parent(s) and to go through additional screening from the airline, all of which is designed to prevent trafficking of children.

Visa and Health Requirements

Some countries require you to get a visa before entry, and some may require that you show proof of certain vaccinations or negative tests for diseases such as yellow fever, although these health requirements usually aren’t an issue if you’re coming straight from the United States. They may come into play if you spend any time in countries that are known to harbor yellow fever or other disease. The International Air Transport Association’s very helpful Passport, Visa & Health page is an excellent source for determining which documents you need before checking in for international travel.


Heads-up: Certain countries, including Madagascar, Panama, Grenada, Tanzania and Trinidad and Tobago require inbound flights to be treated with an aerosol insecticide while passengers are aboard. Other countries also require a "disinsection" treatment, but they may allow residual methods in place of an aerosol spray.

Are You Sure That's an International Flight?

Before you hustle to renew your passport or secure a visa, make sure that the flight you’re getting on actually is international. Many travelers are unaware that the U.S. territories of Puerto Rico, Guam, Saipan and the U.S. Virgin Islands are, in fact, considered domestic destinations, so U.S. citizens don’t need a passport to visit them.

Immigration, Customs and Preclearance

As a general rule, you’ll go through immigration and customs when you arrive at your international destination. Immigration is the point at which you and your passport are checked for permission to be in that country. On the other hand, customs is the authority at your destination country at which you declare items of value that you’re bringing into the country and, in some cases, pay tax on them. In most travel, as long as you arranged any required visas beforehand and aren’t carrying items that trigger a customs inspection, both processes are quick and easy.

If you’re returning to the United States after an international trip, at some airports, you can go through customs and immigration before boarding the plane, which is known as “preclearance.” Again, the process is generally quick and easy, but check with your airline to see if this is an option for your trip and, if so, how much earlier you should arrive at the airport. If you’re not traveling at peak times, an extra 30 minutes is usually a safe bet.


Think you have all your check-in bases covered? Don't forget to leave extra time for typical hassles like getting a shuttle between airport terminals.

Now that the generalities of checking in for international flights are out of the way, here's a look at international check in policies for several major airlines:

Delta Airlines

Delta recommends that international travelers arrive at the airport three hours before their flight’s departure time. You and any checked bags must be checked in at least 60 minutes before departure time, and you should be at the boarding gate at least 45 minutes before the flight departs. If you miss either of those deadlines, you’re almost definitely going to miss your plane, and you’ll have to pay change fees to be rebooked.

There are a few notable exceptions: If you’re traveling to Moscow, Russia, Delta requires you to check in your bags three hours before departure. If you’re going to Dublin, Ireland, you should check in four hours beforehand, even if you’re traveling without luggage, and be at the gate 60 minutes before departure. And if you’re going to Accra, Ghana, check in three to four hours before departure (regardless of whether you’re bringing checked bags) and be at the gate at least two hours before the flight departs.

United Airlines

For most United Airlines flights, you must check in at a civilized 60 minutes’ time before your flight’s scheduled departure, regardless of whether you’re taking checked baggage with you. Some notable exceptions to this are international flights to Micronesia and Marshall Islands (check in at least 90 minutes before departure); Dublin and Lima (you should check in 75 minutes beforehand); and Manila (check in 90 minutes before your flight departs).

Although United doesn’t issue a hard and fast guideline for the time you should be at the boarding gate, they “encourage” you to be there no later than 30 minutes before your flight’s departure time, and minimum arrival times do apply in certain airports. Most notably, you should be at the departure gate 60 minutes beforehand for trips out of Brussels, Kosrae, Kwajalein, Majuro, Pohnpei, Truk and Yap.

American Airlines

American Airlines has a relatively simple policy for international travel: You can check in via mobile app until 90 minutes before an international flight, or check in at the airport (and check bags, if necessary) until 60 minutes before your flight’s departure time. Although you can check bags before then, there is often a limit. For example, you can’t check bags more than four hours in advance of your flight when departing from Portland, Salt Lake City, Seattle, Orlando, Las Vegas, Fort Lauderdale or Denver.

Iceland Air

As with other major carriers, you can check in for your international Iceland Air flight in person, online or at a self-service check-in kiosk at many airports, including Boston, Chicago O’Hare, Denver and Seattle. At some airports, you’ll also find self-service bag drops for checked bags; make sure you check in at the kiosk and tag your bags before leaving them to be checked through on your flight.

KLM Airlines

KLM Airlines, one of Europe’s largest air carriers, has an international check-in policy that’s very similar to those of its American counterparts. Arrive at the airport two hours beforehand for flights within Europe or three hours beforehand for flights to a different continent. At most airports, you and your bags will need to be checked in by 60 minutes before the flight’s scheduled departure.

Lufthansa Airlines

Like all major airlines, Lufthansa offers you the choice of checking in online, through a mobile app or at a check-in kiosk, although not all airports have check-in kiosks available. In San Francisco, for example, you must check in online or through the mobile app. Regardless of how you’re checking in, Lufthansa generally requires you to have your boarding pass in hand and have all your checked baggage accounted for at the baggage drop-off counter no less than 60 minutes before the flight’s scheduled departure time when departing from U.S. airports.

Turkish Airlines

Another enormous international carrier, Turkish Airlines, toes a similar line with its check-in policy. Check-in desks close 60 minutes before international flights, so if you and your baggage aren’t there in time, you’re out of luck. Although you can check in online, you still need to be at the airport and have your bags checked by one hour before the scheduled departure time of your flight.


Even if you're very familiar with an airline's policy for checked baggage on domestic flights, take a minute to double-check their policy for international flights. In some cases, booking an international flight means you're entitled to one or two free checked bags, but this varies by airline and destination.