In most cases, if you are changing planes but staying with the same airline, you do not need to claim and re-check your bags. When you check your bags at the first airport, ask the agent to check them through to your final destination. When you arrive at the intervening airport, go on to your next gate. If you gate-checked a needed item such as a mobility scooter or baby carrier, it will be returned to you at the connecting airport, where you can gate-check it again on the next flight.
If you are changing airlines, find out whether your first airline has an interline agreement with the next. Interline agreements allow both passengers and bags to travel freely among participating airlines. You can typically check your bags through to your final destination, but you must tell the check-in agent what you want to do. Agents’ computers do not typically show the full itinerary for routes that involve multiple airlines. Have your agent manually confirm that your checked bags are properly routed to your destination.
Not all airlines have interline agreements. For example, Southwest Airlines does not have an interline agreement with any other airline, even AirTran, which Southwest owns. Some airlines participate in frequent flier mile partnerships but not interline agreements with some other airlines. If the airlines you are flying do not have an interline agreement with each other, you must claim your bags at the connecting airport and re-check them onto the next flight.
All nations set their own laws and regulations for air travel, customs and immigration. When traveling internationally, you are bound by the laws of the countries in which you travel and by the policies of the airlines. For example, you might need to check your bags in order to go through customs at your arrival airport before transferring to a domestic flight. Always check with the airlines well in advance of your trip for the most updated information.
