Whether a standby passenger pays for a flight depends entirely on their "Standby Category." For airline employees, retirees, and their eligible dependents (often called "non-rev" or non-revenue travelers), the flights are either free or require only a small payment for taxes and security fees. These passengers are only given a seat if the flight is not full. However, for the general public, "Revenue Standby" usually occurs when a passenger wants to switch to an earlier or later flight on the same day they were originally scheduled to fly. Many airlines, such as Delta or United, allow this for free for their elite status members, while standard ticket holders may have to pay a "Same-Day Standby" fee (typically ranging from $50 to $75). It is important to note that you must already possess a valid, paid ticket for that route to be eligible for standby. In 2026, with flights often operating at near-capacity, the "free" standby option is becoming rarer, as airlines prefer to sell those last-minute seats as "Confirmed Same-Day Changes" to maximize their revenue and ensure the passenger actually has a seat.