There is a lot of fraud in the airline business sadly. And also, the computer system requires one. It does not require an address to create the booking, but an address is required to pay for the booking. To create the booking, just a name and phone number is required plus the itinerary as basic information.

Your physical home address generally does not matter for the actual booking of a flight, but it is often required for the billing process and for international security protocols. When you purchase a ticket, the airline or booking site requires an address primarily to verify your credit card (billing address). However, for international travel in 2026, you will likely encounter the "Advance Passenger Information System" (APIS). This system requires you to provide the address of where you will be staying at your destination (such as a hotel or a friend's house), which is a mandatory requirement for customs and immigration authorities in countries like the U.S. and those in the EU. Additionally, for certain security programs like TSA PreCheck or the new EU ETIAS/EES systems, your permanent residential address is used for background verification. While a typo in your home address won't typically prevent you from flying, ensuring that your "Address at Destination" is accurate is crucial for avoiding delays at the immigration counter upon arrival.