No, you do not use the same boarding pass for a round trip. A boarding pass is a security-sensitive document specific to a single flight segment, date, and time. For a standard round-trip journey, you will have at least two separate boarding passes: one for your departure and one for your return. Even if you check in for both flights at the same time (which is rare unless the trip is very short), the system will generate two distinct barcodes. Each pass contains unique data for that specific leg of the journey, including the flight number, gate information, and often a unique security sequence number. If you have a connecting flight, you will receive even more passes—one for every single plane you board. In 2026, most travelers use digital boarding passes on their smartphones via apps like Apple Wallet or Google Wallet; while they stay in the same app, you must swipe or tap to the specific "return" pass when it's time to head home. Using an outdated pass at a security checkpoint or gate will result in an error, as the scanners are programmed to validate only the flight currently boarding.