Traveling on connecting flights operated by different airlines can sometimes feel complicated, especially when it comes to managing luggage. For passengers flying internationally or even domestically with multiple airlines, understanding what happens to their bags between flights is crucial. This is where the concept of interline baggage comes into play. Knowing what interline baggage means, how it works, and what the rules are can help travelers avoid delays, confusion, or the frustration of retrieving and rechecking their luggage during layovers.
Understanding Interline Baggage
What Is Interline Baggage?
Interline baggage refers to the agreement between two or more airlines to transfer a passenger’s checked luggage from one flight to another when those flights are operated by different carriers. This type of baggage handling is especially common when airlines have a commercial agreement known as an ‘interline agreement.’ These agreements allow your luggage to be checked through to your final destination, even if you’re flying with different airlines on a single itinerary.
How Interline Agreements Work
An interline agreement is a formal partnership between two airlines that simplifies passenger service and logistics. When such an agreement is in place, the airlines agree to cooperate in checking baggage, sharing booking systems, and supporting passengers throughout their journey. The primary benefit is the convenience of not having to collect and recheck bags at every stop.
Types of Interline Baggage
One-Way Interline
In a one-way interline arrangement, only one airline agrees to accept baggage from another. For example, Airline A may agree to accept bags from Airline B but not vice versa. This arrangement still provides some level of convenience, but it can require a passenger to retrieve and recheck bags on the return journey.
Mutual Interline
This is the most seamless version, where both airlines have agreed to handle baggage for each other’s passengers in both directions. This is common among airlines that are part of the same alliance or frequently codeshare flights.
When Interline Baggage Applies
Single Ticket Itineraries
Interline baggage usually applies when all flights are booked under a single ticket or booking reference. If your flights are purchased together in one transaction, and the airlines involved have an interline agreement, your baggage will typically be checked through to your final destination automatically.
Separate Ticket Itineraries
If you book your flights on separate tickets, even with airlines that have interline agreements, the rules can change. In many cases, airlines will require you to collect your bags and recheck them. Some may make exceptions, but this varies and should not be assumed without confirmation during check-in.
Benefits of Interline Baggage
Seamless Travel Experience
The biggest advantage of interline baggage is convenience. It eliminates the hassle of collecting and rechecking bags at connecting airports, especially helpful for tight layovers.
Time-Saving
Without the need to claim baggage between flights, travelers save valuable time and can move directly to the next gate or pass through immigration and security faster.
Reduced Risk of Lost Baggage
With interline agreements, airlines coordinate more closely, using tracking systems that help prevent luggage from being misrouted or left behind during transfers.
Limitations and Considerations
Airline Alliances
Most interline agreements exist among airlines in the same alliance, such as Star Alliance, Oneworld, or SkyTeam. Flights booked within the same alliance increase the likelihood of interline baggage being handled smoothly.
Low-Cost Carriers
Budget airlines and low-cost carriers typically do not participate in interline agreements. If your itinerary involves a mix of full-service and budget airlines, you’ll likely need to handle baggage transfers yourself.
Airport Requirements
Even with interline agreements, some airports may require passengers to collect luggage due to customs and immigration processes, particularly on international layovers. In these cases, passengers may need to clear customs with their bags and then recheck them for the connecting flight.
Tips for Managing Interline Baggage
Verify at Check-In
Always confirm at the initial check-in desk whether your baggage will be tagged through to your final destination. This avoids misunderstandings and gives you time to prepare if you need to recheck it.
Keep Boarding Passes Handy
You may be asked to show your next flight’s boarding pass or booking reference at the check-in counter, especially if different airlines are involved.
Allow Enough Connection Time
Even if your baggage is being interlined, make sure your itinerary allows enough time to switch flights, especially in large or unfamiliar airports.
Label Your Bags Clearly
Include your name, phone number, and email on your checked baggage. If it does get delayed or misrouted, this information helps staff locate you quickly.
Understanding Baggage Fees and Policies
Whose Policy Applies?
When flying with multiple carriers, the baggage policy of the ‘marketing carrier’ on the first segment of the journey usually applies to the entire trip. This includes the number of free checked bags, weight limits, and oversize fees.
Handling Inconsistencies
If the baggage policies differ between airlines, it’s important to know which one sets the terms. This is especially relevant for international flights where carriers may have significantly different baggage allowances.
Real-Life Scenarios
Example 1: Seamless Transfer
A passenger books a flight from New York to Tokyo via London with British Airways and Japan Airlines. Since both airlines are part of the Oneworld alliance and the ticket is booked as a single itinerary, the luggage is checked in at JFK and transferred automatically through Heathrow to Tokyo.
Example 2: No Interline Available
Another traveler books separate tickets one with a low-cost airline from Los Angeles to Chicago, and another with a full-service airline from Chicago to Frankfurt. Because the first airline doesn’t have an interline agreement, the traveler must collect their baggage in Chicago and recheck it for the Frankfurt leg.
Future of Interline Baggage
Technology Improvements
Airlines are adopting better tracking and digital tagging systems, which make interline baggage more reliable. Mobile apps and RFID tags are being used to improve visibility and reduce baggage mishandling.
Growing Partnerships
With the rise of codesharing and airline alliances, more carriers are forming partnerships to make interline services smoother for passengers. The future likely holds even greater integration and convenience.
Interline baggage plays a key role in making multi-airline travel smoother and more efficient. By understanding how interline agreements work and how to navigate the policies involved, travelers can enjoy a more convenient and stress-free journey. Whether you’re flying internationally or on a multi-leg domestic trip, knowing the rules around interline baggage can save you time, effort, and unnecessary headaches. For the frequent flyer or the occasional traveler alike, it’s a concept worth knowing well.