Yes, you strictly require a valid same-day boarding pass to use a Priority Pass membership to enter an airport lounge. The program is designed specifically for "departing" passengers, and lounge receptionists are required to scan your boarding pass along with your membership card (physical or digital) to verify you are a traveler. In 2026, many lounges also accept an "arrival" boarding pass if you are in transit between two flights, but you generally cannot use the pass to enter a lounge after your final flight has landed unless the specific lounge is located in a "public" or "arrivals" area (which is rare). Furthermore, the name on your Priority Pass account must match the name on your boarding pass. If you are a "gate-pass" holder or an employee on a "non-revenue" ticket, you can still use the pass as long as you have a confirmed seat assignment and a boarding document. This rule ensures that lounge capacity is reserved for active travelers who are currently navigating the terminal for a flight.