Cheap flights from Ontario, CA to Seattle, WA

Flights starting at £36. Choose between Frontier Airlines, Alaska Airlines, or Flair Airlines to find the best price.

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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 Frontier Airlines, Alaska Airlines, Flair Airlines, Harbour Air (Priv), and Spirit Airlines. Ontario and Seattle have 161 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 08.04 - Sun 14.04

AirlineMon 08.04Tue 09.04Wed 10.04Thu 11.04Fri 12.04Sat 13.04Sun 14.04
4334433
---11---------1
---------------1---
---------------------

Weekly direct flights for Mon 15.04 - Sun 21.04

AirlineMon 15.04Tue 16.04Wed 17.04Thu 18.04Fri 19.04Sat 20.04Sun 21.04
4333434
1---------------1
------11------1
---------------------

Weekly direct flights for Mon 22.04 - Sun 28.04

AirlineMon 22.04Tue 23.04Wed 24.04Thu 25.04Fri 26.04Sat 27.04Sun 28.04
4334534
111111---
------1---1------
---------------------

Weekly direct flights for Mon 29.04 - Sun 05.05

AirlineMon 29.04Tue 30.04Wed 01.05Thu 02.05Fri 03.05Sat 04.05Sun 05.05
3334434
12---------------
---------------------
---------------------

Check-in for a flight from Ontario to Seattle

NameCarrier codeIATA CodePassport needed during bookingOnline check-in available
Frontier AirlinesFFTF9NoOpens 24 days before flight
Closes 1 hours before flight
Alaska AirlinesASAASNoOpens 24 days before flight
Closes 1 hours before flight
Flair AirlinesFLEF8YesOpens 24 days before flight
Closes 1 hours before flight
Harbour Air (Priv)HESYBNoNo
Spirit AirlinesNKSNKNoOpens 24 days before flight
Closes 1 hours before flight

Weather in Seattle

Average Weather

MonthAverage monthly max temperatureAverage monthly min temperature
January7°C2°C
February8°C1°C
March10°C3°C
April13°C4°C
May18°C8°C
June21°C10°C
July25°C13°C
August26°C14°C
September22°C11°C
October15°C7°C
November10°C4°C
December6°C1°C
Hottest Month
26°C
August
Coldest month
1°C
February
Sunny days
250
days per year
Snow days
5
days per year

14 day forecast

Thursday
4 Apr
81%
9°C4°C
11 Apr
18°C7°C
Friday
5 Apr
13°C3°C
12 Apr
88%
10°C5°C
Saturday
6 Apr
84%
10°C5°C
13 Apr
13°C3°C
Sunday
7 Apr
89%
10°C3°C
14 Apr
14°C3°C
Monday
8 Apr
13°C2°C
15 Apr
82%
11°C7°C
Tuesday
9 Apr
84%
13°C8°C
16 Apr
80%
11°C5°C
Wednesday
10 Apr
16°C6°C
17 Apr
89%
10°C4°C

Frequently asked questions

How long does it take to travel from Ontario to Seattle?
What is the flight distance between Ontario and Seattle?
What airlines offer nonstop (direct) flights between Ontario and Seattle?
What are the most popular routes to and from Ontario?
What are the most popular routes to and from Seattle?
What airports are near Ontario?
What airports are near Seattle?
Is it possible to combine flights, buses, and trains in one itinerary when traveling between Ontario and Seattle?
What is Virtual Interlining and how do I use it?
Which airlines fly between Ontario and Seattle?
When's the best time to travel between Ontario and Seattle?
What flights operate between Ontario and Seattle?
How many airports are there near Ontario?
How many airports are there near Seattle?
What time do nonstop (direct) flights between Ontario and Seattle depart?
What time do nonstop (direct) flights between Ontario and Seattle arrive?
What time do flights between Ontario and Seattle depart?
What time do flights between Ontario and Seattle arrive?

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Flights from Ontario

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