HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Ontario

$41+ 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 5/25. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — ONT
Apr 29 — May 61
Tue 4/29
Tue 5/6
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Washington to Ontario with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

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 April 24, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$100
(Kiwi.com)

One-way from

$41
(Frontier)

Popular in

November

Cheapest in

January

Average price

$237

Good round-trip deal

$174 or less

Good one-way deal

$98 or less
Provider with most accurate pricing for Seattle/Tacoma Intl-Los Angeles flight deals.
Search Deals
Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-Los Angeles flights.
Search Deals
From Washington to Ontario
Search Deals
One-way flight from Washington to Ontario
Search Deals
Highest demand for flights based on searches. 12% potential increase in price ($29 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($5 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in April 2025
Search Deals
Price to beat on a round-trip flight from Washington to Ontario.
Search Deals
Price to beat on a one-way flight from Washington to Ontario.
Search Deals

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 April 24, 2025.

This Kiwi.com deal was found by Cheapflights users on 4/23. 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 6/111:50 pmSEA - ONT
Nonstop2h 40mFrontier
Tue 6/1710:03 amONT - SEA
Nonstop2h 46mFrontier
Deal found 4/23$100
This Orbitz deal was found by Cheapflights users on 4/22. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/203:53 pmSEA - ONT
Nonstop2h 32mMultiple Airlines
Tue 5/2711:35 amONT - SEA
Nonstop3h 01mMultiple Airlines
Deal found 4/22$128
This Cheapflightsfares deal was found by Cheapflights users on 4/23. 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.
Tue 7/112:18 pmPDX - ONT
Nonstop2h 20mFrontier
Tue 7/153:35 pmONT - PDX
Nonstop2h 23mFrontier
Deal found 4/23$133
This Expedia deal was found by Cheapflights users on 4/22. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/2911:04 amPDX - ONT
Nonstop2h 20mMultiple Airlines
Sat 5/3110:00 amONT - PDX
Nonstop2h 22mMultiple Airlines
Deal found 4/22$153
This Alaska Airlines deal was found by Cheapflights users on 4/23. 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.
Wed 5/145:55 pmSEA - ONT
Nonstop2h 34mAlaska Airlines
Tue 5/206:00 amONT - SEA
Nonstop2h 42mAlaska Airlines
Deal found 4/23$157
This Delta deal was found by Cheapflights users on 4/23. 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 5/173:35 pmSEA - ONT
Nonstop2h 45mDelta
Tue 5/202:55 pmONT - SEA
Nonstop3h 00mDelta
Deal found 4/23$167
This United Airlines deal was found by Cheapflights users on 4/23. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/213:56 pmPDX - ONT
1 stop4h 38mUnited Airlines
Wed 5/286:00 amONT - PDX
1 stop6h 33mUnited Airlines
Deal found 4/23$172
This Hawaiian Airlines deal was found by Cheapflights users on 4/22. 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 Hawaiian Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/99:42 pmPDX - ONT
Nonstop2h 16mHawaiian Airlines
Mon 5/128:59 pmONT - PDX
Nonstop2h 21mHawaiian Airlines
Deal found 4/22$177
This Southwest deal was found by Cheapflights users on 4/22. 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 5/136:45 amPDX - ONT
1 stop3h 25mSouthwest
Tue 5/206:20 amONT - PDX
1 stop4h 05mSouthwest
Deal found 4/22$192
This Alaska Airlines deal was found by Cheapflights users on 4/21. 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.
Wed 5/149:42 pmPDX - ONT
Nonstop2h 16mAlaska Airlines
Sat 5/177:30 amONT - PDX
Nonstop2h 20mAlaska Airlines
Deal found 4/21$197
This United Airlines deal was found by Cheapflights users on 4/23. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/2411:40 amSEA - ONT
1 stop5h 59mUnited Airlines
Wed 5/281:36 pmONT - SEA
1 stop4h 49mUnited Airlines
Deal found 4/23$205
This Southwest deal was found by Cheapflights users on 4/23. 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.
Thu 5/156:00 amSEA - ONT
1 stop5h 00mSouthwest
Mon 5/194:55 pmONT - SEA
1 stop7h 35mSouthwest
Deal found 4/23$227

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 April 24, 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

Wed 6/11

1:50 pm-4:30 pm

Nonstop2h 40m

Ontario

Tue 6/17

10:03 am-12:49 pm

Nonstop2h 46m

$100

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Tue 5/20

3:53 pm-6:25 pm

Nonstop2h 32m

Ontario

Tue 5/27

11:35 am-2:36 pm

Nonstop3h 01m

$128

PortlandOntario

PDX - ONT

PDXONT

Portland

Tue 7/1

12:18 pm-2:38 pm

Nonstop2h 20m

Ontario

Tue 7/15

3:35 pm-5:58 pm

Nonstop2h 23m

$133

PortlandOntario

PDX - ONT

PDXONT

Portland

Thu 5/29

11:04 am-1:24 pm

Nonstop2h 20m

Ontario

Sat 5/31

10:00 am-12:22 pm

Nonstop2h 22m

$153

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Wed 5/14

5:55 pm-8:29 pm

Nonstop2h 34m

Ontario

Tue 5/20

6:00 am-8:42 am

Nonstop2h 42m

$157

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Sat 5/17

3:35 pm-6:20 pm

Nonstop2h 45m

Ontario

Tue 5/20

2:55 pm-5:55 pm

Nonstop3h 00m

$167

PortlandOntario

PDX - ONT

PDXONT

Portland

Wed 5/21

3:56 pm-8:34 pm

1 stop4h 38m

Ontario

Wed 5/28

6:00 am-12:33 pm

1 stop6h 33m

$172

PortlandOntario

PDX - ONT

PDXONT

Portland

Fri 5/9

9:42 pm-11:58 pm

Nonstop2h 16m

Ontario

Mon 5/12

8:59 pm-11:20 pm

Nonstop2h 21m

$177

PortlandOntario

PDX - ONT

PDXONT

Portland

Tue 5/13

6:45 am-10:10 am

1 stop3h 25m

Ontario

Tue 5/20

6:20 am-10:25 am

1 stop4h 05m

$192

PortlandOntario

PDX - ONT

PDXONT

Portland

Wed 5/14

9:42 pm-11:58 pm

Nonstop2h 16m

Ontario

Sat 5/17

7:30 am-9:50 am

Nonstop2h 20m

$197

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/22

Showing 1-10 of 59 results
1
2
3
...
6

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 April 24, 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 April 24, 2025.

The most flights from USWA to ONT are scheduled on a Wednesday (17 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (7 on average).

Rainfall in Ontario by month

Plan your trip to Ontario by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Ontario ranges from 0.1 - 3.4 inches per month. February is typically the wettest month, when rainfall can reach 3.4 in. June is typically the driest time to visit Ontario when rainfall is around 0.1 in.

Temperature in Ontario by month

Plan your trip to Ontario by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Ontario, use this chart to help with planning. For those seeking warmer temperatures, August is the ideal time of year to visit, when temperatures reach an average of 78.8 F. Travelers looking to avoid the cold should look outside of December, when temperatures are typically at their lowest (around 53.6 F).

Reviews of airlines servicing Ontario

Get insights into the airlines that provide service to Ontario. 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 Ontario. Reviews last updated April 24, 2025.
To help decide which airline to fly from Washington to Ontario, see what other customers have to say about Alaska Airlines, Southwest and Delta. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
9,918 reviews

Comfort

7.9

Crew

8.5

Overall

8.0

Entertainment

7.1

Boarding

8.2

Food

7.1

Reviews

1 / 20
4.0
Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >
Alaska Airlines
8.0
Very good
9,918 reviews
Alaska Airlines
8.0
Very good
9,918 reviews

Comfort

7.9

Crew

8.5

Overall

8.0

Entertainment

7.1

Boarding

8.2

Food

7.1

Reviews

1 / 20
4.0
Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >
Southwest
8.0
Very good
4,287 reviews
Alaska Airlines
8.0
Very good
9,918 reviews

Comfort

7.9

Crew

8.5

Overall

8.0

Entertainment

7.1

Boarding

8.2

Food

7.1

Reviews

1 / 20
4.0
Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >
Delta
8.0
Very good
7,920 reviews
Alaska Airlines
8.0
Very good
9,918 reviews

Comfort

7.9

Crew

8.5

Overall

8.0

Entertainment

7.1

Boarding

8.2

Food

7.1

Reviews

1 / 20
4.0
Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >
Hawaiian Airlines
7.9
Good
2,393 reviews
Alaska Airlines
8.0
Very good
9,918 reviews

Comfort

7.9

Crew

8.5

Overall

8.0

Entertainment

7.1

Boarding

8.2

Food

7.1

Reviews

1 / 20
4.0
Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >
United Airlines
7.4
Good
8,685 reviews
Alaska Airlines
8.0
Very good
9,918 reviews

Comfort

7.9

Crew

8.5

Overall

8.0

Entertainment

7.1

Boarding

8.2

Food

7.1

Reviews

1 / 20
4.0
Okay

Anonymous,Apr 2025

LAS - STS

flight was delayed both ways even tho the weather was clear >

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 69 times in the past calendar month.

  • 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 $41 on Frontier. Other airlines that offer cheap prices include Hawaiian Airlines from $79 and Southwest 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 WestJet (98%), Korean Air (97%) and KLM (95%).

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

    The cheapest flight price from State of Washington to Ontario is $55. On average you can expect to pay $304. The most popular route, (Seattle/Tacoma Intl - Ontario), can usually be booked for $86.

  • 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.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Washington to Ontario

See prices for flight routes from nearby airports that may be better suited for you.
John F Kennedy Intl to Los Angeles flights
Newark to Los Angeles flights
Newark to Las Vegas flights
John F Kennedy Intl to San Francisco flights
Seattle to Los Angeles flights
O'Hare Intl to Las Vegas flights
John F Kennedy Intl to Las Vegas flights
Newark to San Francisco flights
Seattle to Las Vegas flights
Dallas/Fort Worth to Las Vegas flights
LaGuardia to Los Angeles flights
LaGuardia to Las Vegas flights
Dulles Intl to Los Angeles flights
San Jose to Los Angeles flights
Hobby to Las Vegas flights
San Francisco to Los Angeles flights
Denver to Las Vegas flights
Reagan-National to Los Angeles flights
Los Angeles to Las Vegas flights
San Francisco to Las Vegas flights
Santa Ana to Las Vegas flights
Dulles Intl to Las Vegas flights
Boston to Los Angeles flights
John F Kennedy Intl to Ontario flights
Burbank to Las Vegas flights
Dallas/Fort Worth to Los Angeles flights
Los Angeles to San Francisco flights
Oakland to Los Angeles flights
O'Hare Intl to Los Angeles flights
Boston to Las Vegas flights
Oakland to Las Vegas flights
Baltimore to Las Vegas flights
George Bush Intcntl to Las Vegas flights
Los Angeles to San Jose flights
Baltimore to Los Angeles flights
Seattle to Santa Ana flights
John F Kennedy Intl to San Diego flights
Newark to Burbank flights
Minneapolis to Las Vegas flights
Reagan-National to Las Vegas flights
Dulles Intl to San Francisco flights
Los Angeles to Oakland flights
LaGuardia to San Francisco flights
Midway to Las Vegas flights
Dallas/Fort Worth to San Francisco flights
Reagan-National to San Francisco flights
Atlanta to Las Vegas flights
Seattle to San Diego flights
San Jose to Las Vegas flights
Seattle to Burbank flights

Top 7 airlines flying from Washington to Ontario

Discover the top 7 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 April 24, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$40Average$96FlexibilityNo cancel feeOn-time65%
FrontierCheapest$55Average$137FlexibilityNo cancel feeOn-time62%
Hawaiian AirlinesCheapest$95Average$228FlexibilityNo cancel feeOn-time85%
DeltaCheapest$117Average$306FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$136Average$447FlexibilityNo cancel feeOn-time75%
SouthwestCheapest$196Average$356FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$308Average$443FlexibilityNo cancel feeOn-time69%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.