Washington

$64+ Cheap flights from Ontario (ONT) to Washington

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 3/1. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SEA
Jan 12 — Jan 191
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Cheap flight deals from Ontario to Washington

Cheapest flights from Ontario to Washington
Explore the most affordable flight options available from Ontario to Washington. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 13, 2025.

This Super.com deal was found by Cheapflights users on 12/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/216:37 pmONT - SEA
1 stop15h 34mFrontier
Sun 1/116:48 pmSEA - ONT
Nonstop2h 35mFrontier
Deal found 12/13$138
This Kiwi.com deal was found by Cheapflights users on 12/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/226:00 pmONT - SEA
1 stop16h 11mFrontier
Sun 1/116:48 pmSEA - ONT
Nonstop2h 35mFrontier
Deal found 12/12$144
This Frontier deal was found by Cheapflights users on 12/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/246:00 amONT - SEA
1 stop7h 51mFrontier
Mon 1/511:06 amSEA - ONT
Nonstop2h 36mFrontier
Deal found 12/10$161
This Kiwi.com deal was found by Cheapflights users on 12/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/226:00 pmONT - SEA
1 stop16h 11mFrontier
Thu 1/86:48 pmSEA - ONT
Nonstop2h 35mFrontier
Deal found 12/12$164
This Super.com deal was found by Cheapflights users on 12/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/206:00 amONT - SEA
1 stop5h 31mFrontier
Sun 1/411:06 amSEA - ONT
Nonstop2h 36mFrontier
Deal found 12/12$168
This CheapOair deal was found by Cheapflights users on 12/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/302:45 pmONT - SEA
Nonstop2h 53mFrontier
Mon 1/511:06 amSEA - ONT
Nonstop2h 36mFrontier
Deal found 12/11$173
This Frontier deal was found by Cheapflights users on 12/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/206:00 amONT - SEA
1 stop5h 31mFrontier
Mon 1/511:06 amSEA - ONT
Nonstop2h 36mFrontier
Deal found 12/12$180
This Frontier deal was found by Cheapflights users on 12/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/256:00 amONT - PDX
1 stop7h 24mFrontier
Thu 1/12:19 pmPDX - ONT
1 stop6h 58mFrontier
Deal found 12/11$188
This Frontier deal was found by Cheapflights users on 12/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/236:00 amONT - PDX
1 stop7h 24mFrontier
Thu 1/12:19 pmPDX - ONT
1 stop6h 58mFrontier
Deal found 12/13$214
This Frontier deal was found by Cheapflights users on 12/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/216:00 amONT - PDX
1 stop7h 24mFrontier
Thu 1/12:19 pmPDX - ONT
1 stop6h 58mFrontier
Deal found 12/11$219
This Frontier deal was found by Cheapflights users on 12/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/236:00 amONT - PDX
1 stop7h 24mFrontier
Thu 12/2512:47 pmPDX - ONT
1 stop11h 12mFrontier
Deal found 12/11$238
This CheapOair deal was found by Cheapflights users on 12/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/226:00 pmONT - PDX
1 stop19h 24mFrontier
Thu 12/2512:47 pmPDX - ONT
1 stop11h 12mFrontier
Deal found 12/12$239

Find flight deals from Ontario to Washington

Keep the following information in mind while searching for Ontario to Washington flight deals. Data was last updated December 13, 2025.

Most accurate provider

CheapOair
3 stars

Most trusted provider

CheapOair
3 stars

Round-trip from

$124
(Trip.com)

One-way from

$64
(Frontier)

Popular in

December

Cheapest in

January

Average price

$272

Good round-trip deal

$186 or less

Good one-way deal

$133 or less
Provider with most accurate pricing for Los Angeles-Seattle/Tacoma Intl flight deals.
Provider most trusted by Cheapflights users for Los Angeles-Seattle/Tacoma Intl flights.
From Ontario to Washington
One-way flight from Ontario to Washington
Highest demand for flights based on searches. 1% potential increase in price ($3 potential increase over avg. RT price).
Cheapest flight prices on average. 1% potential price decrease ($5 potential savings vs. average RT price).
Average for round-trip flights in December 2025
Price to beat on a round-trip flight from Ontario to Washington.
Price to beat on a one-way flight from Ontario to Washington.

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ontario to Washington that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated December 13, 2025.
Use the filters below to find and compare flights from Ontario to Washington that are best for you.

Fly from

Ontario

Fly to

Washington

Route

Depart

Return

Price

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sat 1/24

3:30 pm-6:35 pm

Nonstop3h 05m

Seattle/Tacoma Intl

Tue 1/27

5:30 am-12:16 pm

1 stop6h 46m

$129

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Thu 2/26

6:14 am-9:09 am

Nonstop2h 55m

Seattle/Tacoma Intl

Sun 3/1

8:30 am-11:08 am

Nonstop2h 38m

$129

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Fri 1/23

5:10 pm-12:09 am

1 stop6h 59m

Seattle/Tacoma Intl

Mon 1/26

8:07 pm-10:51 pm

Nonstop2h 44m

$129

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sat 1/24

3:30 pm-6:35 pm

Nonstop3h 05m

Seattle/Tacoma Intl

Mon 1/26

4:55 pm-11:58 pm

1 stop7h 03m

$129

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Tue 1/20

5:10 pm-12:09 am

1 stop6h 59m

Seattle/Tacoma Intl

Sat 1/24

11:15 am-1:56 pm

Nonstop2h 41m

$129

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sun 1/25

6:00 am-8:54 am

Nonstop2h 54m

Seattle/Tacoma Intl

Tue 1/27

12:31 pm-3:08 pm

Nonstop2h 37m

$139

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Fri 2/27

6:14 am-9:09 am

Nonstop2h 55m

Seattle/Tacoma Intl

Sun 3/1

8:56 pm-11:32 pm

Nonstop2h 36m

$139

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Thu 1/22

5:10 pm-12:09 am

1 stop6h 59m

Seattle/Tacoma Intl

Sat 1/24

5:00 am-12:16 pm

1 stop7h 16m

$139

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sat 2/14

6:00 am-12:25 pm

1 stop6h 25m

Seattle/Tacoma Intl

Tue 2/17

7:00 pm-11:49 pm

1 stop4h 49m

$139

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sat 1/31

4:03 pm-6:54 pm

Nonstop2h 51m

Seattle/Tacoma Intl

Sun 2/8

8:25 am-1:06 pm

1 stop4h 41m

$149

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/12

Showing 1-10 of 60 results
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Best time to book a flight from Ontario to Washington

Have a flexible travel schedule? Discover the best time to fly to Washington from Ontario with our price prediction graph.
Estimated round-trip 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.

Cheapflights Insights

Everything you need to know about your flight from Ontario to Washington

What is the cheapest month to book a flight from Ontario to State of Washington?

Currently, January is the cheapest month in which you can book a flight from Ontario to State of Washington (average of $38). Flying from Ontario to State of Washington in November is currently the most expensive (average of $94). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from ONT to WA?

Find hourly flight availability from Ontario to Washington. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated December 13, 2025.

One of the essential ways to save on airfare from Ontario to State of Washington is to remain as flexible as possible. Flights that are in the evening tend to be the most expensive. A flight at noon could potentially save you up to 17% on airfare.

What is the cheapest day to fly from Ontario to State of Washington?

Use this chart to determine the cheapest time to fly round-trip from Ontario to Washington. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Ontario to State of Washington flight should consider departing on Saturday mornings when fares are most often at their lowest. Monday evenings flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from Ontario to State of Washington

Explore weekly flight availability from Ontario to Washington. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated December 13, 2025.

The most flights from ONT to USWA are scheduled on a Friday (20 on average). You will have fewer flight options on Thursday, which is when the least amount of flights are scheduled (8 on average).

Reviews of airlines servicing Washington

Get insights into the airlines that provide service to Washington. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Washington. Reviews last updated December 13, 2025.
Get a feel of what it's like to fly with Alaska Airlines, Southwest, and Delta from Ontario to Washington by reading reviews from past customers. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.

Comfort

7.8

Overall

8.0

Boarding

8.1

Crew

8.5

Entertainment

7.0

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.

Comfort

7.8

Overall

8.0

Boarding

8.1

Crew

8.5

Entertainment

7.0

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.

Comfort

7.8

Overall

8.0

Boarding

8.1

Crew

8.5

Entertainment

7.0

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.

Comfort

7.8

Overall

8.0

Boarding

8.1

Crew

8.5

Entertainment

7.0

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.

Comfort

7.8

Overall

8.0

Boarding

8.1

Crew

8.5

Entertainment

7.0

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.

Comfort

7.8

Overall

8.0

Boarding

8.1

Crew

8.5

Entertainment

7.0

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Dec 2025

SJC - SEA

The flight was great. Don’t have to make it better. Everything was OK.

Related info for your journey

Find useful and relevant information for your journey from Ontario to Washington. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
  • What airport do you fly from for flights from Ontario to Washington?

    Located just 3.1 mi from the city center, Ontario (ONT) is the airport most travelers will use when flying to Washington from Ontario.

  • How popular is this Ontario to State of Washington flight route?

  • How long is the flight from Ontario to State of Washington?

    For as low as $129, Delta can have you in State of Washington from Ontario in 2h 55m. Ontario and State of Washington are separated by a distance of 956 mi. This flight may include one or multiple stops.

  • What are the cheapest airlines to fly from Ontario to State of Washington one-way?

    For one-way options, check prices for Frontier. According to our data, you can fly for as low as $44. Users have also found prices from $78 and $80 on Southwest and Alaska Airlines, respectively.

  • What are the most popular routes from Ontario to State of Washington?

  • What are the most reliable airlines from Ontario to State of Washington?

    Before booking your flight to State of Washington from Ontario, check out the most reliable airlines to get you to your destination on time: Virgin Atlantic (97%), KLM (96%), Korean Air( 95%).

  • What are the cheapest flights from Ontario to State of Washington?

    Looking at all options, your cheapest flight can be booked for $47. While the most popular route (Ontario - Seattle/Tacoma Intl) can be booked for $91 on average, our data indicates $433 when flying from Ontario to State of Washington.

  • Can I find deals for flights from Ontario to Washington that include hotel bookings?

    Yes. In addition to deals on Ontario to Washington flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ontario to Washington?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to Washington.

  • Can I find deals for business class flights from Ontario to Washington?

    Yes. Cheapflights offers flight deals from Ontario to Washington by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Ontario to State of Washington?

    Currently, January is the cheapest month in which you can book a flight from Ontario to State of Washington (average of $38). Flying from Ontario to State of Washington in November is currently the most expensive (average of $94). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Alternative routes for Ontario to Washington

See prices for flight routes from nearby airports that may be better suited for you.

Top 6 airlines flying from Ontario to Washington

Discover the top 6 airlines that operate flights from Ontario to Washington. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated December 13, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$84Average$177FlexibilityNo cancel feeOn-time62%
Hawaiian AirlinesCheapest$98Average$315FlexibilityNo cancel feeOn-time85%
DeltaCheapest$118Average$256FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$148Average$396FlexibilityNo cancel feeOn-time75%
SouthwestCheapest$150Average$293FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$218Average$367FlexibilityNo cancel feeOn-time69%

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