Distance From Boeing Field King County International Airport to Ulaanbaatar Chinggis Khaan International Airport, BFI - UBN Distance

The distance from Boeing Field King County International Airport (BFI) to Ulaanbaatar Chinggis Khaan International Airport (UBN) is 5229 miles or 8415 kilometers or 4541 nautical miles.

The distance shown below is direct flight distance between airports. Straight-line distance does not account for the surface between the two points. It is the distance a bird or airplane would travel between the two points when flying above the surface. The straight line distance is the direct route between two points, regardless of whether or not there are roads that connect them.

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How long does it take to travel from Seattle ( United States ) to Ulaanbaatar (Sergelen) ( Mongolia )?

A one-way nonstop (direct) flight between Seattle and Ulaanbaatar (Sergelen) takes around 12 hours 1 minutes.

Estimated flight time from Boeing Field King County International Airport, Seattle, United States to Ulaanbaatar Chinggis Khaan International Airport, Ulaanbaatar (Sergelen), Mongolia is 12 hours 1 minutes under avarage conditions. Your actual flying time may vary depending on wind direction/speed or weather conditions. This calculation does not include the departure and landing times of the aircraft. In addition, it does not cover the person identity check, ticket check-in and baggage collection times at the airport.

Travel Distance Between the Airports • BFI - UBN

Kilometers		8415 km
Statute Miles		5229 miles
Nautical Miles		4541 nm
Avg. Time of Flight		12 hours 1 minutes

Boeing Field King County International Airport to Ulaanbaatar Chinggis Khaan International Airport Flight Route Map - BFI to UBN Flight Path

Location of Boeing Field King County International Airport & Ulaanbaatar Chinggis Khaan International Airport is given below.
Click the map to view Seattle to Ulaanbaatar (Sergelen) nonstop flight path and travel direction.

Click to see flight route on Google Map between Seattle, United States and Ulaanbaatar (Sergelen), Mongolia. .

Nonstop flight route between Seattle, United States and Ulaanbaatar (Sergelen), Mongolia.

Time Difference Between the Airports • BFI - UBN

Time difference between Seattle (United States) and Ulaanbaatar (Sergelen) (Mongolia) is 15 Hours.
Ulaanbaatar (Sergelen) time is 15 Hours ahead of Seattle.

Location	Local Time
Seattle (United States)	2025-12-15, 23:54:13 MST
Ulaanbaatar (Sergelen) (Mongolia)	2025-12-16, 14:54:13 +08

Why should you arrive 3 hours before international flight? Flyers who are traveling to an international destination should arrive at the airport earlier than domestic flyers. This is because international flights can have additional check-in requirements, like passport verification, that need to be completed before you receive your boarding pass.

Origin

Boeing Field King County International Airport (BFI / KBFI) Seattle, United States

Destination

Ulaanbaatar Chinggis Khaan International Airport (UBN / ZMCK) Ulaanbaatar (Sergelen), Mongolia