Cheap flights from Ontario, CA to Seattle, WA
Flights starting at £42. Choose between Alaska Airlines, Frontier Airlines, or United Airlines to find the best price.
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Cheapest one-way trip | £78 |
---|---|
Cheapest round-trip | £140 |
Average round-trip | £146 |
Nonstop flights in May | £42 – £240 |
Most popular airline | Alaska Airlines |
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Book your trip to arrive at Seattle–Tacoma International, or Kenmore Air Harbor Seaplane Base. The distance between Ontario and Seattle is 1542 km. The most popular airlines for this route are Alaska Airlines, Frontier Airlines, and United Airlines. Ontario and Seattle have 44 direct flights per week.
Weekly direct flights
Discover the top airlines offering direct flights from Ontario to Seattle in the next month. You’ll find the number of daily direct flights per airline in the table.
Weekly direct flights for Mon 29.04 - Sun 05.05
Airline | Mon 29.04 | Tue 30.04 | Wed 01.05 | Thu 02.05 | Fri 03.05 | Sat 04.05 | Sun 05.05 |
---|---|---|---|---|---|---|---|
2 | 3 | 3 | 4 | 4 | 3 | 4 | |
--- | --- | --- | --- | --- | --- | --- | |
--- | --- | --- | --- | --- | --- | --- |
Weekly direct flights for Mon 06.05 - Sun 12.05
Airline | Mon 06.05 | Tue 07.05 | Wed 08.05 | Thu 09.05 | Fri 10.05 | Sat 11.05 | Sun 12.05 |
---|---|---|---|---|---|---|---|
4 | 3 | 3 | 4 | 4 | 3 | 4 | |
--- | --- | --- | --- | --- | --- | --- | |
--- | --- | --- | --- | --- | --- | --- |
Weekly direct flights for Mon 13.05 - Sun 19.05
Airline | Mon 13.05 | Tue 14.05 | Wed 15.05 | Thu 16.05 | Fri 17.05 | Sat 18.05 | Sun 19.05 |
---|---|---|---|---|---|---|---|
4 | 3 | 3 | 4 | 4 | 4 | 4 | |
--- | --- | --- | 1 | --- | 1 | 1 | |
--- | --- | --- | --- | --- | --- | --- |
Weekly direct flights for Mon 20.05 - Sun 26.05
Airline | Mon 20.05 | Tue 21.05 | Wed 22.05 | Thu 23.05 | Fri 24.05 | Sat 25.05 | Sun 26.05 |
---|---|---|---|---|---|---|---|
4 | 4 | 4 | 4 | 4 | 4 | 4 | |
1 | 1 | 1 | 1 | 1 | 1 | 1 | |
--- | --- | --- | --- | --- | --- | --- |
Check-in for a flight from Ontario to Seattle
Name | Carrier code | IATA Code | Passport needed during booking | Online check-in available |
---|---|---|---|---|
Alaska Airlines | ASA | AS | No | Opens 24 days before flight Closes 1 hours before flight |
Frontier Airlines | FFT | F9 | No | Opens 24 days before flight Closes 1 hours before flight |
United Airlines | UAL | UA | Yes | No |
Weather in Seattle
Average Weather
Month | Average monthly max temperature | Average monthly min temperature |
January | 7°C | 2°C |
February | 8°C | 1°C |
March | 10°C | 3°C |
April | 13°C | 4°C |
May | 18°C | 8°C |
June | 21°C | 10°C |
July | 25°C | 13°C |
August | 26°C | 14°C |
September | 22°C | 11°C |
October | 15°C | 7°C |
November | 10°C | 4°C |
December | 6°C | 1°C |
14 day forecast
Frequently asked questions
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