$1,561 Cheap Korean Air flights St. Louis (STL) to Kathmandu (KTM)

Apply the "Price (lowest to highest)" filter on Expedia to find cheap Korean Air round-trip flights from $1,838 from STL to KTM. Affordable one-way tickets from $1,561 are also available.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.

Start your search for Korean Air flights from STL to KTM about one month before you want to go. The cheapest time to book an international flight is usually 18 to 29 days ahead of your departure date when you can save 17% versus booking four to five months in advance. No matter your itinerary or fare class, the best day of the week to book international airfare is usually Sunday. Friday can be the most expensive. Travelers booking on a Sunday can save an average of 17% compared to those who book on a Friday.**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.

Search Korean Air's earliest flights from STL to KTM by selecting the "Early Morning" and "Morning" filters. Not only will you get to where you're going sooner, early departures also experience 20% fewer cancellations.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.

Offering a 5-star airline rating, Korean Air is a favorite of many passengers departing from STL to KTM. Plus, if you're a Korean Airlines Skypass and One Key™ member booking through Expedia, you could earn OneKeyCash™* on eligible flights on top of your airline miles.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.