A boarding pass or boarding card is a document provided by an airline during airport check-in, giving a passenger permission to enter the restricted area of an airport (also known as the airside portion of the airport) and to board the airplane for a particular flight. At a minimum, it identifies the passenger, the flight number, the date, and scheduled time for departure. A boarding pass may also indicate details of the perks a passenger is entitled to (e.g., lounge access, priority boarding) and is thus presented at the entrance of such facilities to show eligibility.

In some cases, flyers can check in online and print the boarding passes themselves. There are also codes that can be saved to an electronic device or from the airlines app that are scanned during boarding. A boarding pass may be required for a passenger to enter a secure area of an airport.

Generally, a passenger with an electronic ticket will only need a boarding pass. If a passenger has a paper airline ticket, that ticket (or flight coupon) may be required to be attached to the boarding pass for the passenger to board the aircraft. For "connecting flights", a boarding pass is required for each new leg (distinguished by a different flight number), regardless of whether a different aircraft is boarded or not.

The paper boarding pass (and ticket, if any), or portions thereof, are sometimes collected and counted for cross-check of passenger counts by gate agents, but more frequently are scanned (via barcode or magnetic strip) and returned to the passengers in their entirety. The standards for bar codes and magnetic stripes on boarding passes are published by the IATA. The bar code standard (Bar Coded Boarding Pass) defines the 2D bar code printed on paper boarding passes or sent to mobile phones for electronic boarding passes. The magnetic stripe standard (ATB2) expired in 2010.

Most airports and airlines have automatic readers that will verify the validity of the boarding pass at the jetway door or boarding gate. This also automatically updates the airline's database to show the passenger has boarded and the seat is used, and that the checked baggage for that passenger may stay aboard. This speeds up the paperwork process at the gate.

During security screenings, the personnel will also scan the boarding pass to authenticate the passenger.

Once an airline has scanned all boarding passes presented at the gate for a particular flight and knows which passengers actually boarded the aircraft, its database system can compile the passenger manifest for that flight.