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₹ 9,101+ Direct flights from Ontario

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 17/3. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
ONT — SEA
1 Mar — 8 Mar1
1 adult
1 adult, Economy, 0 bags

Direct flights from Ontario

Enter your travel dates to find the best prices.

Cheapest flights from Ontario
Explore the most affordable flight options available from Ontario. Find the lowest fares based on data from user searches, with prices last updated on 30 January 2026.

Sat 14/306:14
ONT
-
SEA
Nonstop2h 55m
Alaska Airlines
Tue 17/308:30
SEA
-
ONT
Nonstop2h 38m
Alaska Airlines
Deal found 29/1₹ 14,432
Sat 28/212:02
ONT
-
SEA
Nonstop2h 50m
Alaska Airlines
Sun 1/308:30
SEA
-
ONT
Nonstop2h 38m
Alaska Airlines
Deal found 30/1₹ 15,351
Thu 26/216:02
ONT
-
SEA
Nonstop2h 50m
Alaska Airlines
Sun 1/320:56
SEA
-
ONT
Nonstop2h 36m
Alaska Airlines
Deal found 30/1₹ 16,271
Sat 14/316:02
ONT
-
SEA
Nonstop2h 50m
Alaska Airlines
Sat 28/321:24
SEA
-
ONT
Nonstop2h 35m
Alaska Airlines
Deal found 28/1₹ 17,190
Fri 13/316:02
ONT
-
SEA
Nonstop2h 50m
Alaska Airlines
Mon 16/308:30
SEA
-
ONT
Nonstop2h 38m
Alaska Airlines
Deal found 30/1₹ 18,109
Tue 17/206:14
ONT
-
SEA
Nonstop2h 55m
Hawaiian Airlines
Sun 22/220:56
SEA
-
ONT
Nonstop2h 36m
Hawaiian Airlines
Deal found 28/1₹ 18,936
Mon 9/306:00
ONT
-
SEA
Nonstop2h 54m
Delta
Tue 10/319:50
SEA
-
ONT
Nonstop2h 43m
Delta
Deal found 29/1₹ 19,028
Sat 21/306:00
ONT
-
SEA
Nonstop2h 55m
Delta
Thu 26/308:30
SEA
-
ONT
Nonstop2h 48m
Delta
Deal found 28/1₹ 19,948
Tue 24/212:02
ONT
-
SEA
Nonstop2h 50m
Alaska Airlines
Sun 1/320:56
SEA
-
ONT
Nonstop2h 36m
Alaska Airlines
Deal found 30/1₹ 20,407
Fri 20/306:00
ONT
-
SEA
Nonstop2h 55m
Delta
Sun 22/319:50
SEA
-
ONT
Nonstop2h 44m
Delta
Deal found 29/1₹ 20,867
Mon 27/410:39
ONT
-
SEA
Nonstop2h 51m
Alaska Airlines
Thu 30/421:17
SEA
-
ONT
Nonstop2h 42m
Alaska Airlines
Deal found 29/1₹ 21,786
Fri 20/206:14
ONT
-
SEA
Nonstop2h 55m
Alaska Airlines
Sat 21/208:30
SEA
-
ONT
Nonstop2h 38m
Alaska Airlines
Deal found 28/1₹ 22,246

Find direct flights from Ontario within your budget

 
Use the slider to find direct flights from Ontario within your budget. Price data is based on user searches made on Cheapflights. Over the past seven days, Cheapflights users made 454,620 searches. This data was last updated on 30 January 2026.

Fly to

Seattle

Route

Depart

Return

Price

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Wed 11/3

06:14-09:09

Nonstop2h 55m

Seattle/Tacoma Intl

Wed 18/3

21:24-23:59

Nonstop2h 35m

₹ 14,432

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Tue 12/5

17:55-20:50

Nonstop2h 55m

Seattle/Tacoma Intl

Sat 16/5

19:55-22:40

Nonstop2h 45m

₹ 14,432

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sat 14/3

16:02-18:52

Nonstop2h 50m

Seattle/Tacoma Intl

Tue 17/3

12:30-15:08

Nonstop2h 38m

₹ 14,432

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Wed 11/3

06:00-08:54

Nonstop2h 54m

Seattle/Tacoma Intl

Sat 14/3

19:50-22:33

Nonstop2h 43m

₹ 14,432

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sat 14/3

06:14-09:09

Nonstop2h 55m

Seattle/Tacoma Intl

Wed 18/3

21:24-23:59

Nonstop2h 35m

₹ 14,432

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sat 28/2

06:14-09:09

Nonstop2h 55m

Seattle/Tacoma Intl

Tue 3/3

20:05-22:44

Nonstop2h 39m

₹ 14,432

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Tue 14/4

14:20-17:24

Nonstop3h 04m

Seattle/Tacoma Intl

Mon 20/4

19:50-22:37

Nonstop2h 47m

₹ 15,351

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Tue 24/2

06:14-09:09

Nonstop2h 55m

Seattle/Tacoma Intl

Sun 1/3

08:30-11:08

Nonstop2h 38m

₹ 15,351

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Thu 5/3

16:02-18:52

Nonstop2h 50m

Seattle/Tacoma Intl

Sat 7/3

08:30-11:08

Nonstop2h 38m

₹ 15,351

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sat 14/3

16:02-18:52

Nonstop2h 50m

Seattle/Tacoma Intl

Mon 16/3

08:30-11:08

Nonstop2h 38m

₹ 15,351

Flights are sorted by cheapest return flights first.

Deals found on 28/1

Showing 1-10 of 22 results
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Best time to book a flight from Ontario

Have a flexible travel schedule? Discover the best time to fly from Ontario with our price prediction graph.
Estimated return price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Related info for your journey

Access useful and relevant information related to your journey from Ontario. This can include details such as airport transportation, visa requirements, travel insurance, luggage regulations, and any other information that can ensure a smooth and hassle-free travel experience. Please note that the information is based on general guidance and may need to be verified with official sources. Data last updated 30 January 2026.

  • Where can you fly direct from Ontario?

    Currently, the most popular direct flight destination from Ontario is Denver.

  • What is the best time of year to fly direct from Ontario?

    If you're seeking the lowest price on a direct flight from Ontario, February is worth consideration as prices are at their lowest, on average. In terms of the number of daily non-stop flights, January offers travelers the most options.

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