The flight distance from Washington Dulles International Airport (IAD) in Washington, United States to St. Mary's Airport (ISC) in St. Mary's, United Kingdom is 5,568 kilometers (3,460 miles / 3,006 nautical miles). The estimated flight time for this route is approximately 8h, flying northeast at a heading of 53°.

This is a long-haul route typically operated by wide-body aircraft such as the Boeing 777 or Airbus A350. Full meal service, in-flight entertainment, and comfort amenities are standard.

This is an international route connecting United States with United Kingdom. It is an intercontinental flight between North America and Europe. Travelers should check visa requirements, customs regulations, and any travel advisories before booking.

Time zone information: When it's 14:00 in Washington, it's 19:00 in St. Mary's. The 5-hour time difference may cause some jet lag. Most travelers adjust within a day or two.

The return flight from St. Mary's (ISC) to Washington (IAD) follows a heading of 286° (west 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 Washington Dulles International Airport (IAD) and St. Mary's Airport (ISC) detail pages, or use our flight duration calculator to compare other routes.