Yes, most airlines impose a "No-Show" penalty, but it usually isn't a separate "fee" you pay out-of-pocket; rather, it is the forfeiture of your entire ticket value. If you miss the first leg of a round-trip or multi-city flight without notifying the airline, they will almost always cancel all remaining segments of your itinerary without a refund. Some airlines may allow you to rebook for a fee (typically $100–$500 plus the fare difference), but this is usually only possible if you call before the flight departs. If you miss the flight due to circumstances beyond your control (like a flat tire), many agents follow an informal "flat tire rule," allowing you to stand by for the next flight for free if you arrive within two hours of departure. However, this is a courtesy, not a guaranteed right, and varies significantly by carrier.