The flight distance from St Mary's Airport (KSM) in St Mary'S, United States to Seattle-Tacoma International Airport (SEA) in Seattle, United States is 3,017 kilometers (1,874 miles / 1,629 nautical miles). The estimated flight time for this route is approximately 5h, flying east southeast at a heading of 103°.

This is a medium-haul route that may be operated by either narrow-body or wide-body aircraft depending on demand. Passengers can expect a meal service on most carriers.

This is a domestic route within United States. Both airports operate in the same country, which may simplify travel requirements and documentation. Despite being a domestic route, there is a 1-hour time difference between the two cities.

Time zone information: When it's 00:49 in St Mary'S, it's 01:49 in Seattle.

The return flight from Seattle (SEA) to St Mary'S (KSM) follows a heading of 318° (northwest). Actual flight times may vary depending on wind conditions, air traffic, and the specific aircraft used.

For more information about these airports, visit the St Mary's Airport (KSM) and Seattle-Tacoma International Airport (SEA) detail pages, or use our flight duration calculator to compare other routes.