In most cases, if you are traveling on a single ticket (PNR) with the same airline or its partners, your checked bag is "checked through" to your final destination. This means the ground crew will handle the transfer between aircraft, and you do not need to reclaim it at your layover city. However, there are two major exceptions. First, if you have booked separate tickets on different airlines, you must almost always collect your bag and re-check it for the next flight. Second, if you are arriving from an international location and connecting to a domestic flight in certain countries like the United States, Canada, or Australia, you must legally clear customs at the first point of entry. In this scenario, you retrieve your bag, carry it through the customs checkpoint, and then drop it off at a designated "Transfer" or "Bag Drop" belt just outside the secure area. Always check the "Final Destination" code on your printed bag tag to confirm exactly where your luggage is headed.