Everything you need to know to book a flight

If you’re flying domestically (within your own country), you don’t typically need a passport or passport number. If you’re booking an international flight, however, you’ll need your valid passport and passport details in order to do so.

You've done the research, picked your destination, and figured out your travel dates. The next step in your travel plans can be one of the most exciting but also the most nerve-wracking: booking your flight.

In order to successfully book a flight, you'll need a handful of details and documents at the ready. But once you have all the information you need to book a flight, you'll be one step closer to taking to the skies and going on your next adventure.

Passport details

If you're traveling internationally, you will need an active passport in order to book your flight. Be sure to check the expiration date of your passport as well to ensure it doesn't expire before your return. Depending on which country you're visiting, you also may need to ensure it doesn't expire within a certain amount of time. For example, travel to much of Europe requires a passport to be valid for at least three months following the date of departure. So even if your intended return date is before your passport expires, ensure you follow the destination's guidelines to enable seamless travel.

Once you have confirmed that you have your passport and that it's valid for the time you want to travel, you'll need to note its key details to book your international flight.

You’ll typically need your name, date of birth, place of birth, passport issue and expiry date, nationality, and passport number from the document. Today, many mobile apps also allow you to take a picture of your passport and auto-import the data listed here. Still, you'll want to check that all the details are correct before booking your flight.

Travel dates and times

In order to book a flight, you'll need to know the dates and times you want to travel. If you have an exact date in mind, you'll be able to search the airline website for your exact dates of travel and get a list of available departure and arrival times.

However, if your dates are flexible, many airlines also offer the ability to select a flexible option when searching, which will show you a matrix of prices across different departure days and months. This feature can enable you to book the cheapest flight if you’re more open with your travel dates.

Whichever option you choose, you’ll want to also look for departing and arrival times of the day of your flight. Understanding these options and picking the appropriate departure and arrival time can save a lot of headaches at the airport. For instance, if you're considering an early morning departure, be sure to factor in enough airport arrival time to make it through bag check and security. While that 8 a.m. flight might look appealing, keep in mind you'll have to arrive at the airport much earlier in order to get to the gate on time.

Many international flights may arrive a day later than your departure time, so if you need to be somewhere on a specific day, pay attention to when the flight actually arrives. Red-eye flights (flights that depart late at night and arrive early in the morning) also typically have different departure and arrival dates.

Departure and arrival airports

When you're booking a flight, you will also need to know the airport where you would like to depart from and the airport where you'd like to arrive. You'll need to be more specific than the city name, especially if you’re flying to large metros like New York or London that have multiple airports.

When you're searching for a flight, you can put in the city name and it will display one or more airports that fly to that city. You can check a specific airport, or if you’re less particular about a specific airport in those bigger cities, you can select “all airports" to see a list of all the flights across the different airports a city has. This will give you the most options across a number of different price ranges. Remember to also calculate transportation costs and travel time for different airports to your final destination to make sure you have a full picture of the cost and efficiency of the different options.

Passenger details

When you’ve picked the flights you want, you'll need to enter basic information about yourself and your fellow travelers. This includes your full name, date of birth, gender, contact phone number and email, and passport number if you're booking an international flight.

The airline will typically also ask if you have a Known Traveler Number (KTN) and/or a frequent flier awards program for that airline. The Known Traveler number typically is issued through optional programs like TSA Pre and Global Entry that help you get through security faster. If you have these numbers, you should enter them when you’re booking a flight to ensure a smooth check in, but if you don’t have them, you can skip this part of the passenger details section. You can typically also add these later, as long as you enter them before your departure.

Where you want to sit on the plane

Once you’ve found and selected the flights you want, and put in some initial information to book the flight, you’ll often have the option to select your seats. Depending on the fare class you selected, you might be able to select a seat with no charge or select a seat with a fee. Some basic fares won’t allow you to pre-select a seat, but don't worry, you’ll get your seat during the airline check-in process.

Any seat charge that you select during the checkout process will be added to your total flight cost. However, keep in mind that these fees are charged separately from your flight itself and aren't always refundable if you change or cancel your flight. Be sure to check the airline’s terms and conditions to know your options if you need to switch your flight.

Method of payment

Once you’ve selected your travel times, your departure and arrival airports, selected your seats and entered your passenger details, you're almost done with all the info you need to book a flight. You’ll get a chance to review those details and then enter your payment information to purchase the flight and any add-ons you selected.

Typically airlines give you a number of ways to book including a debit or credit card, services like PayPal, or Buy Now Pay Later services like Klarna. Enter your payment details, review the cost and flight details, and click purchase. You’ll have successfully booked your flight. The airline should display a confirmation code and also email you that code. This code will help the airlines easily pull up your flight if you need assistance, so keep it in a safe and easy-to-access place.

FAQs about booking flights

What info do I need to book a flight for someone else?

If you’re booking a flight for someone else, you’ll need the same information as for yourself. This includes their name, date of birth, gender, passport number (if booking internationally), and optionally their Known Traveler number and frequent flier number.

Can I book a flight without a passport?

If you’re flying domestically (within your own country), you don’t typically need a passport or passport number. If you’re booking an international flight, however, you’ll need your valid passport and passport details in order to do so.

Can I change the information on a flight booking if it’s incorrect?

If you make a mistake while you’re booking, don't worry, you can correct most details online or by calling an airline agent. When calling the airline, make sure you have your confirmation code so they can easily find your booking. Tell the agent what you need to correct and they’ll make the change and reissue any documents you need to fly. Remember to double check any new confirmation emails to make sure the errors have been corrected on the new flight booking.