In 2026, the cost of flying "standby" is generally $0 (free) on most major U.S. carriers like Delta, United, and American, provided you are trying to catch an earlier flight on the same day as your original booking. This is known as "Same-Day Standby." You can add yourself to the list via the airline's app or at a kiosk, and you are only cleared if a seat remains open after all confirmed passengers and "elite" members have boarded. However, it is important to distinguish this from "Same-Day Confirmed" travel. While standby is free and offers no guarantee of a seat, a "Same-Day Confirmed" change usually costs around $75 for general members (though it is often free for Gold, Platinum, and Diamond elite status holders). This fee guarantees you a seat on a different flight, allowing you to bypass the uncertainty of the standby list. For travelers who have missed a flight due to an airline delay, standby is always free. For those looking to voluntarily change their plans, "free standby" is the ultimate budget-friendly "pro" move, provided you have the flexibility to wait at the gate.