Booking flights using your favorite airline’s loyalty rewards program can provide great value for your points or miles — and not only with that one carrier. Many airlines participate in alliances that allow you to book flights on partner airlines. These partnerships open up a world of possibilities by potentially increasing the value of your rewards and providing more flight options for your trip. We’ve created a quick breakdown of how partner airlines work so you can better understand the major airline alliances and how to book award flights within them.

What are partner airlines?

Airlines want to offer their customers as many destinations around the world as possible to make travel with them easy and accessible. However, it likely isn't profitable or feasible for one airline to fly everywhere that a traveler wants to go.

One way around this is for an airline to partner with other airlines and share routes. This allows a passenger to book flights through one airline yet be serviced by others. For some itineraries, this means that you won't even fly on a plane owned by the airline that you booked the flight through.

For example, instead of American Airlines and British Airways both flying half-full planes between New York City and London, they may pair up and offer a codeshare flight. The plane is a mix of American Airlines and British Airways passengers, while the plane is owned and operated by just one of the airlines. Both airline websites will list these tickets for sale.

While this concept may seem confusing at first, it helps to keep costs down and airplanes full between different city pairs.

Earn miles and elite status when flying partner airlines

Aside from additional flight inventory to choose from, another perk of partner airlines is the ability to credit your flight to a partner airline’s loyalty program. When you fly on one carrier, you can enter your loyalty member information for one of their partner airlines to receive credit for that flight.

This helps you avoid having a large amount of miles spread across multiple programs with only a small amount of miles in each. Instead, you can concentrate your rewards in your preferred airline’s loyalty program, which might also accelerate your progress toward elite status with that airline.

Receive reciprocal benefits on partner airlines

When you have elite status with one airline, you may be eligible for reciprocal benefits with other partner airlines. Depending on the airline and your status level, these benefits can include extra baggage allowance, priority boarding, preferred seating and complimentary airport lounge access. The details vary from one partner to another, but airline websites typically spell out the benefits you are eligible to receive based on your status.

Book flights on partner airlines with miles

You typically aren’t able to transfer miles between partner airlines (or any airlines). But what you can do is use your loyalty program points to book an award flight on a partner airline. While searching for a flight on your favorite airline’s website, choose the option to book or redeem using points or miles. Search results will include award travel on any available partner airline. Just select the partner flight you want, and you can continue the booking process to reserve a partner award ticket.