Great-circle route IAH ↔ SEA. Faint dots are other airports, for geographic context. Download this map — free to reuse with a link back to this page.
Frequencies below are per direction, from our most recent schedule sample.
| Direction | Frequency | Days | Airlines |
|---|---|---|---|
| IAH → SEA Houston to Seattle |
53/wk | Daily | Alaska Airlines, United Airlines |
| SEA → IAH Seattle to Houston |
53/wk | Daily | Alaska Airlines, United Airlines |
Where a direction shows “—” we track it as an operating nonstop but hold no schedule sample for it — we would rather show nothing than guess.
In 2025, airlines reported 611,914 passengers on 4,164 flights between IAH and SEA — about 1,677 a day — filling 87% of the 703,610 seats flown. United Air Lines Inc. carried the most passengers (58%).
Source: US DOT T-100 segment reports — actual airline-reported traffic, scheduled service only, both directions combined. Cargo and charter flights excluded.
2 airlines fly the IAH–SEA nonstop, including Alaska Airlines, United Airlines.
Recent scheduled departures on this route have used the Boeing 737, Boeing 737-900, Boeing 737-800, Airbus A320.
Aircraft assignments change by season and by time of day.
On a long east–west route like this one the two directions do not take the same time. Aircraft flying eastbound ride the mid-latitude jet stream and typically arrive earlier than the westbound leg, which flies into it. The difference is commonly 30 to 90 minutes on transatlantic and transpacific flights, and it varies by season. The estimate above does not model wind — treat it as a midpoint and check the airline's own timetable for the block time on your date.
The distance between George Bush Intercontinental Houston Airport and Seattle Tacoma International Airport is 1,872 miles, or 3,013 kilometres.
| Great-circle distance | 1,872 mi |
| Kilometres | 3,013 km |
| Nautical miles | 1,627 nmi |
Measured airport to airport. The actual track is longer — aircraft follow airways, avoid restricted airspace and route around weather.
Yes. 2 airlines fly the route nonstop, with about 106 departures a week across both directions. The route is in our live nonstop dataset, last seeded 2026-07-07.
About 4h 13m in the air. That is a great-circle estimate from the 1,872-mile distance, not a scheduled block time — an airline's published time will differ by roughly 15 to 45 minutes depending on routing, winds and taxi.
About 53 a week from Houston to Seattle and 53 a week from Seattle to Houston, from our most recent schedule sample.
Alaska Airlines, United Airlines.
In 2025, airlines reported 611,914 passengers on 4,164 scheduled flights between IAH and SEA — about 1,677 a day — filling 87% of the seats flown. Source: US DOT T-100 segment reports, both directions combined.
Recent scheduled departures have used the Boeing 737, Boeing 737-900, Boeing 737-800, Airbus A320. Assignments change by season and by time of day.
