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$63+ Cheap flights from Washington to Ontario (ONT)

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 11/1. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — ONT
Oct 10 — Oct 171
Fri 10/10
Fri 10/17
1 adult, Economy
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Cheap flight deals from Washington to Ontario

Keep the following information in mind while searching for Washington to Ontario flight deals. Data was last updated September 10, 2025.

Round-trip from

$96
(Kiwi.com)

One-way from

$63
(Southwest)

Popular in

December

Cheapest in

January

Average price

$186

Good round-trip deal

$157 or less

Good one-way deal

$120 or less
From Washington to Ontario
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One-way flight from Washington to Ontario
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Highest demand for flights based on searches. 3% potential increase in price ($7 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($4 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Price to beat on a round-trip flight from Washington to Ontario.
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Price to beat on a one-way flight from Washington to Ontario.
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Find flight deals from Washington to Ontario

Cheapest flights from Washington to Ontario
Explore the most affordable flight options available from Washington to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 10, 2025.

This Kiwi.com deal was found by Cheapflights users on 9/10. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/1512:43 pmPDX - ONT
1 stop11h 07mFrontier
Mon 10/208:32 amONT - PDX
Nonstop2h 26mFrontier
Deal found 9/10$96
This CheapOair deal was found by Cheapflights users on 9/10. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/37:17 pmPDX - ONT
Nonstop2h 21mFrontier
Tue 10/77:04 amONT - PDX
1 stop28h 44mFrontier
Deal found 9/10$98
This Southwest deal was found by Cheapflights users on 9/8. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/86:15 amPDX - ONT
1 stop4h 00mSouthwest
Tue 10/142:25 pmONT - PDX
1 stop6h 55mSouthwest
Deal found 9/8$104
This Frontier deal was found by Cheapflights users on 9/10. 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.
Sat 10/47:15 amPDX - ONT
1 stop12h 39mFrontier
Sun 10/58:07 amONT - PDX
Nonstop2h 26mFrontier
Deal found 9/10$105
This Priceline deal was found by Cheapflights users on 9/10. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/107:30 pmPDX - ONT
Nonstop2h 22mFrontier
Mon 10/138:32 amONT - PDX
Nonstop2h 26mFrontier
Deal found 9/10$106
This Booking.com deal was found by Cheapflights users on 9/9. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/312:51 pmPDX - ONT
Nonstop2h 19mFrontier
Fri 11/712:05 pmONT - PDX
Nonstop2h 26mFrontier
Deal found 9/9$107
This Cheapflightsfares deal was found by Cheapflights users on 9/9. 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.
Fri 10/247:30 pmPDX - ONT
Nonstop2h 22mFrontier
Sun 10/268:25 amONT - PDX
Nonstop2h 26mFrontier
Deal found 9/9$111
This CheapOair deal was found by Cheapflights users on 9/8. 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 10/912:43 pmPDX - ONT
1 stop11h 07mFrontier
Mon 10/138:32 amONT - PDX
Nonstop2h 26mFrontier
Deal found 9/8$112
This Trip.com deal was found by Cheapflights users on 9/9. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/157:17 pmSEA - ONT
1 stop12h 00mFrontier
Mon 11/178:02 amONT - SEA
Nonstop2h 53mFrontier
Deal found 9/9$113
This Southwest deal was found by Cheapflights users on 9/9. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/187:00 amPDX - ONT
1 stop4h 55mSouthwest
Wed 11/195:55 amONT - PDX
1 stop4h 55mSouthwest
Deal found 9/9$114
This Trip.com deal was found by Cheapflights users on 9/9. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/301:18 pmSEA - ONT
1 stop10h 32mFrontier
Sun 11/28:02 amONT - SEA
Nonstop2h 53mFrontier
Deal found 9/9$116
This Cheapflightsfares deal was found by Cheapflights users on 9/10. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/1412:51 pmPDX - ONT
Nonstop2h 19mFrontier
Sun 11/1612:05 pmONT - PDX
Nonstop2h 26mFrontier
Deal found 9/10$117

Cheapflights Fare Finder

 
Customize your flight search to find flights from Washington to Ontario 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 September 10, 2025.
Use the filters below to find and compare flights from Washington to Ontario that are best for you.

Fly from

Washington

Fly to

Ontario

Route

Depart

Return

Price

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Thu 10/23

1:05 pm-7:20 pm

1 stop6h 15m

Ontario

Wed 10/29

5:45 pm-10:55 pm

1 stop5h 10m

$145

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Fri 10/24

6:15 am-10:10 am

1 stop3h 55m

Ontario

Tue 10/28

3:50 pm-10:00 pm

2 stops6h 10m

$159

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Wed 10/8

6:15 am-10:15 am

1 stop4h 00m

Ontario

Wed 10/15

3:50 pm-10:00 pm

2 stops6h 10m

$165

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Sat 10/18

7:05 am-1:00 pm

1 stop5h 55m

Ontario

Sun 10/19

8:00 pm-1:10 am

1 stop5h 10m

$169

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Tue 9/30

11:25 am-2:12 pm

Nonstop2h 47m

Ontario

Wed 11/26

6:00 am-8:54 am

Nonstop2h 54m

$177

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Wed 10/22

8:15 am-11:08 am

Nonstop2h 53m

Ontario

Wed 10/29

11:48 am-2:45 pm

Nonstop2h 57m

$177

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Sat 11/8

7:55 pm-10:41 pm

Nonstop2h 46m

Ontario

Wed 11/12

5:49 pm-8:50 pm

Nonstop3h 01m

$177

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Sat 10/4

9:25 pm-12:03 am

Nonstop2h 38m

Ontario

Tue 10/7

1:31 pm-4:14 pm

Nonstop2h 43m

$177

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Sat 10/4

8:15 am-11:09 am

Nonstop2h 54m

Ontario

Sat 10/11

5:50 pm-8:49 pm

Nonstop2h 59m

$177

PortlandOntario

PDX - ONT

PDXONT

Portland

Wed 10/15

9:30 pm-11:51 pm

Nonstop2h 21m

Ontario

Wed 10/22

5:45 pm-8:03 pm

Nonstop2h 18m

$177

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/9

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

Have a flexible travel schedule? Discover the best time to fly to Ontario from Washington 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 Washington to Ontario

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

Currently, August is the cheapest month in which you can book a flight from State of Washington to Ontario (average of $246). Flying from State of Washington to Ontario in March is currently the most expensive (average of $328). 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 WA to ONT?

Find hourly flight availability from Washington to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 10, 2025.

When flying from State of Washington to Ontario, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

Weekly flight availability from State of Washington to Ontario

Explore weekly flight availability from Washington to Ontario. 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 September 10, 2025.

The most flights from USWA to ONT are scheduled on a Monday (20 on average). You will have fewer flight options on Friday, which is when the least amount of flights are scheduled (5 on average).

Related info for your journey

Find useful and relevant information for your journey from Washington to Ontario. 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 into for flights to Ontario from Washington?

    Most people fly into Ontario (ONT) if they book a flight to Ontario from Washington. Ontario is conveniently located just 3.1 mi from Ontario’s city center.

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

    Flights from Washington to Ontario have been viewed 61 times in the past calendar month.

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

    Airlines like Southwest, Alaska Airlines, and Delta fly from State of Washington to Ontario in about 2h 47m. The time it takes to get you to your destination can typically vary by up to 4h 01m. The distance from State of Washington to Ontario is about 956 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    One-way options have recently been found by users for as low as $63 on Southwest. Other airlines that offer cheap prices include Delta from $69 and Frontier from $94 one-way.

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

    While some choose either Portland - Ontario or Spokane - Ontario, Seattle/Tacoma Intl - Ontario is the most popular route from State of Washington to Ontario.

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

    The top 3 most reliable airlines when flying from State of Washington to Ontario are Scandinavian Airlines (93%), Delta (91%) and Virgin Atlantic (90%).

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

    The cheapest flight price from State of Washington to Ontario is $69. On average you can expect to pay $314. The most popular route, (Seattle/Tacoma Intl - Ontario), can usually be booked for $53.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Washington to Ontario 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 State of Washington to Ontario?

    Currently, August is the cheapest month in which you can book a flight from State of Washington to Ontario (average of $246). Flying from State of Washington to Ontario in March is currently the most expensive (average of $328). 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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Top 6 airlines flying from Washington to Ontario

Discover the top 6 airlines that operate flights from Washington to Ontario. 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 September 10, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$68Average$160FlexibilityNo cancel feeOn-time62%
Hawaiian AirlinesCheapest$98Average$236FlexibilityNo cancel feeOn-time85%
DeltaCheapest$117Average$284FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$129Average$358FlexibilityNo cancel feeOn-time75%
SouthwestCheapest$156Average$319FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$306Average$397FlexibilityNo cancel feeOn-time69%

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