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.

In nearly all cases, you cannot directly transfer miles from one airline's frequent flyer program to another (e.g., you can't move 50,000 Delta SkyMiles into a United MileagePlus account). However, in 2026, you can "use" miles across different airlines through Alliances and Partnerships. For example, if you have United miles, you can use them to book a flight on Lufthansa because they are both in the Star Alliance. A rare exception to the "no transfer" rule is the Avios ecosystem; you can move Avios freely at a 1:1 ratio between British Airways, Qatar Airways, Iberia, and Finnair. Another method involves "transferable points" from credit cards like Amex or Chase, which act as a middleman, allowing you to send points to any of their airline partners. While you can't merge existing airline balances, these alliances ensure that your loyalty to one carrier can still get you a seat on another. Be wary of third-party "mileage broker" sites that claim to swap miles, as these often violate airline terms and can result in your account being shut down.