Yes! If you are a resident of the US and over the age of 18, you can search and book flights on over 600 global airlines and pay using Four, whether that is a domestic flight or an international one!

Yes, in 2026, the "Buy Now, Pay Later" (BNPL) model has become a standard offering across the aviation industry, allowing travelers to split the cost of a flight into four interest-free installments. Services like Klarna, Affirm, Afterpay, and Zip have integrated directly into the checkout pages of major carriers such as Delta, United, and Southwest, as well as booking engines like Expedia and Priceline. Typically, you pay 25% of the total fare at the time of booking, with the remaining three payments due every two weeks over a six-week period. This model is particularly popular for high-cost international flights or last-minute travel where a large upfront payment is difficult. However, it is essential to read the fine print; while many "Pay in 4" options are interest-free, failing to make a payment on time can result in late fees or a negative impact on your credit score. Some airlines also offer their own internal "uplift" programs that allow for longer monthly payment terms with interest, providing a variety of ways to manage travel expenses without draining your immediate cash reserves.