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$55+ 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 1/8. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SEA
Dec 16 — Dec 231
Tue 12/16
Tue 12/23
1 adult, Economy
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Find 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 November 16, 2025.

This Kiwi.com deal was found by Cheapflights users on 11/14. 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.
Sat 12/67:10 amONT - SEA
1 stop4h 39mMultiple Airlines
Sun 12/710:51 amSEA - ONT
Nonstop2h 34mMultiple Airlines
Deal found 11/14$125
This CheapOair deal was found by Cheapflights users on 11/16. 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.
Thu 12/116:15 amONT - SEA
1 stop27h 51mFrontier
Sun 12/146:18 pmSEA - ONT
1 stop19h 46mFrontier
Deal found 11/16$128
This Delta deal was found by Cheapflights users on 11/15. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/134:49 pmONT - SEA
1 stop6h 36mDelta
Fri 1/911:15 amSEA - ONT
Nonstop2h 41mDelta
Deal found 11/15$129
This Delta deal was found by Cheapflights users on 11/16. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/111:29 pmONT - SEA
1 stop5h 07mDelta
Mon 12/152:19 pmSEA - ONT
Nonstop2h 48mDelta
Deal found 11/16$130
This CheapOair deal was found by Cheapflights users on 11/15. 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.
Wed 12/106:15 amONT - SEA
1 stop27h 51mFrontier
Fri 12/1210:51 amSEA - ONT
Nonstop2h 34mFrontier
Deal found 11/15$131
This Frontier deal was found by Cheapflights users on 11/15. 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.
Fri 12/192:45 pmONT - SEA
Nonstop2h 53mFrontier
Sat 1/312:16 pmSEA - ONT
Nonstop2h 39mFrontier
Deal found 11/15$133
This Cheapflightsfares deal was found by Cheapflights users on 11/14. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/136:00 amONT - SEA
Nonstop2h 57mAlaska Airlines
Tue 12/168:43 amSEA - ONT
Nonstop2h 36mAlaska Airlines
Deal found 11/14$137
This Alaska Airlines deal was found by Cheapflights users on 11/14. 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/236:00 amONT - SEA
Nonstop2h 57mAlaska Airlines
Fri 1/29:35 pmSEA - ONT
Nonstop2h 39mAlaska Airlines
Deal found 11/14$138
This CheapOair deal was found by Cheapflights users on 11/15. 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 12/222:45 pmONT - SEA
Nonstop2h 53mFrontier
Mon 12/2911:06 amSEA - ONT
Nonstop2h 36mFrontier
Deal found 11/15$140
This CheapOair deal was found by Cheapflights users on 11/15. 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 12/236:17 pmONT - SEA
1 stop19h 34mFrontier
Fri 1/22:54 pmSEA - ONT
1 stop9h 05mFrontier
Deal found 11/15$141
This CheapOair deal was found by Cheapflights users on 11/15. 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.
Sat 12/275:16 pmONT - SEA
1 stop16h 55mFrontier
Fri 1/211:06 amSEA - ONT
Nonstop2h 36mFrontier
Deal found 11/15$142
This CheapOair deal was found by Cheapflights users on 11/15. 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.
Sat 12/133:20 pmONT - PDX
1 stop20h 36mFrontier
Mon 12/159:31 amPDX - ONT
1 stop11h 46mFrontier
Deal found 11/15$150

Cheap flight deals from Ontario to Washington

Keep the following information in mind while searching for Ontario to Washington flight deals. Data was last updated November 16, 2025.

Most accurate provider

CheapOair
3 stars

Most trusted provider

CheapOair
3 stars

Round-trip from

$124
(Frontier)

One-way from

$55
(Frontier)

Popular in

November

Cheapest in

January

Average price

$272

Good round-trip deal

$194 or less

Good one-way deal

$118 or less
Provider with most accurate pricing for Los Angeles-Seattle/Tacoma Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Los Angeles-Seattle/Tacoma Intl flights.
Search Deals
From Ontario to Washington
Search Deals
One-way flight from Ontario to Washington
Search Deals
Highest demand for flights based on searches. 11% potential increase in price ($27 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($5 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in November 2025
Search Deals
Price to beat on a round-trip flight from Ontario to Washington.
Search Deals
Price to beat on a one-way flight from Ontario to Washington.
Search Deals

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 November 16, 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

Thu 1/29

5:10 pm-12:09 am

1 stop6h 59m

Seattle/Tacoma Intl

Sun 2/1

8:07 pm-10:51 pm

Nonstop2h 44m

$129

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sat 12/13

4:49 pm-11:25 pm

1 stop6h 36m

Seattle/Tacoma Intl

Sat 1/3

8:15 am-11:02 am

Nonstop2h 47m

$129

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Wed 12/17

5:49 pm-8:49 pm

Nonstop3h 00m

Seattle/Tacoma Intl

Tue 1/6

5:25 am-12:16 pm

1 stop6h 51m

$129

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Tue 12/9

6:00 am-12:57 pm

1 stop6h 57m

Seattle/Tacoma Intl

Sun 12/14

8:05 pm-10:47 pm

Nonstop2h 42m

$129

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Wed 12/10

6:00 am-12:57 pm

1 stop6h 57m

Seattle/Tacoma Intl

Sun 12/14

8:05 pm-10:47 pm

Nonstop2h 42m

$129

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Thu 12/18

6:00 am-12:57 pm

1 stop6h 57m

Seattle/Tacoma Intl

Sun 1/4

8:15 am-11:02 am

Nonstop2h 47m

$129

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Thu 12/11

6:40 am-9:45 am

Nonstop3h 05m

Seattle/Tacoma Intl

Mon 12/15

7:11 pm-11:58 pm

1 stop4h 47m

$129

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sat 1/24

7:30 am-10:36 am

Nonstop3h 06m

Seattle/Tacoma Intl

Tue 1/27

4:55 pm-11:58 pm

1 stop7h 03m

$129

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Fri 12/19

6:00 am-8:57 am

Nonstop2h 57m

Seattle/Tacoma Intl

Wed 1/7

12:31 pm-3:08 pm

Nonstop2h 37m

$139

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sat 12/6

6:00 am-12:57 pm

1 stop6h 57m

Seattle/Tacoma Intl

Sun 12/7

5:25 am-12:34 pm

1 stop7h 09m

$139

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/14

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 $89). 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 November 16, 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 16% 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. Sunday at noon 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 November 16, 2025.

The most flights from ONT to USWA are scheduled on a Saturday (18 on average). You will have fewer flight options on Wednesday, 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 November 16, 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.
Alaska Airlines
8.0
Very good
11,302 reviews

Comfort

7.8

Entertainment

7.0

Boarding

8.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why
Alaska Airlines
8.0
Very good
11,302 reviews
Alaska Airlines
8.0
Very good
11,302 reviews

Comfort

7.8

Entertainment

7.0

Boarding

8.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why
Southwest
8.0
Very good
4,245 reviews
Alaska Airlines
8.0
Very good
11,302 reviews

Comfort

7.8

Entertainment

7.0

Boarding

8.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why
Delta
7.9
Good
8,010 reviews
Alaska Airlines
8.0
Very good
11,302 reviews

Comfort

7.8

Entertainment

7.0

Boarding

8.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why
Hawaiian Airlines
7.8
Good
2,809 reviews
Alaska Airlines
8.0
Very good
11,302 reviews

Comfort

7.8

Entertainment

7.0

Boarding

8.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why
Frontier
5.8
Fair
3,109 reviews
Alaska Airlines
8.0
Very good
11,302 reviews

Comfort

7.8

Entertainment

7.0

Boarding

8.1

Overall

8.0

Food

7.1

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why

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?

    This flight path from Ontario to Washington was viewed by 228 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

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

    For as low as $157, Delta can have you in State of Washington from Ontario in 2h 25m. Ontario and State of Washington are separated by a distance of 839 mi. All flights are typically nonstop.

  • 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 $69. Users have also found prices from $76 and $88 on Southwest and Alaska Airlines, respectively.

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

    While some choose either Ontario - Portland or Ontario - Spokane, Ontario - Seattle/Tacoma Intl is the most popular route 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 (98%), KLM (97%), SkyWest Airlines( 97%).

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

    Looking at all options, your cheapest flight can be booked for $60. While the most popular route (Ontario - Seattle/Tacoma Intl) can be booked for $58 on average, our data indicates $499 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 $89). 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.

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Alternative routes for Ontario to Washington

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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 November 16, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$83Average$174FlexibilityNo cancel feeOn-time62%
Hawaiian AirlinesCheapest$98Average$315FlexibilityNo cancel feeOn-time85%
DeltaCheapest$120Average$259FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$150Average$391FlexibilityNo cancel feeOn-time75%
SouthwestCheapest$150Average$307FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$233Average$401FlexibilityNo cancel feeOn-time69%

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