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$57+ 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 5/30. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — ONT
May 12 — May 191
Mon 5/12
Mon 5/19
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 May 7, 2025.

Most accurate provider

CheapOair
3 stars

Most trusted provider

CheapOair
3 stars

Round-trip from

$99
(Cheapflightsfares)

One-way from

$57
(Cheapflightsfares)

Popular in

November

Cheapest in

January

Average price

$207

Good round-trip deal

$148 or less

Good one-way deal

$99 or less
Provider with most accurate pricing for Seattle/Tacoma Intl-Los Angeles flight deals.
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Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-Los Angeles flights.
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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. 12% potential increase in price ($29 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($5 potential savings vs. average RT price).
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Average for round-trip flights in May 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 May 7, 2025.

This Cheapflightsfares deal was found by Cheapflights users on 5/6. 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.
Wed 6/111:50 pmSEA - ONT
Nonstop2h 40mFrontier
Mon 6/1610:03 amONT - SEA
Nonstop2h 46mFrontier
Deal found 5/6$99
This Cheapflightsfares deal was found by Cheapflights users on 5/6. 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 5/3011:04 amPDX - ONT
Nonstop2h 20mFrontier
Mon 6/22:30 pmONT - PDX
Nonstop2h 25mFrontier
Deal found 5/6$104
This Orbitz deal was found by Cheapflights users on 5/6. 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 9/29:30 pmPDX - ONT
Nonstop2h 23mMultiple Airlines
Sun 9/78:25 amONT - PDX
Nonstop2h 26mMultiple Airlines
Deal found 5/6$142
This Frontier deal was found by Cheapflights users on 5/6. 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 5/2012:26 pmGEG - ONT
1 stop11h 33mFrontier
Wed 5/2112:08 amONT - GEG
1 stop10h 56mFrontier
Deal found 5/6$158
This Southwest deal was found by Cheapflights users on 5/6. 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.
Sat 8/307:55 amSEA - ONT
1 stop4h 35mSouthwest
Wed 9/178:15 amONT - SEA
1 stop5h 05mSouthwest
Deal found 5/6$160
This Hawaiian Airlines deal was found by Cheapflights users on 5/7. 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.
Wed 9/105:46 pmGEG - ONT
1 stop6h 13mHawaiian Airlines
Sat 9/277:22 pmONT - GEG
1 stop4h 37mHawaiian Airlines
Deal found 5/7$168
This American Airlines deal was found by Cheapflights users on 5/6. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/33:18 pmGEG - ONT
1 stop6h 39mAmerican Airlines
Tue 6/106:23 amONT - GEG
1 stop6h 58mAmerican Airlines
Deal found 5/6$169
This Alaska Airlines deal was found by Cheapflights users on 5/5. 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 8/207:03 amPDX - ONT
Nonstop2h 23mAlaska Airlines
Sat 8/237:10 amONT - PDX
Nonstop2h 17mAlaska Airlines
Deal found 5/5$177
This Delta deal was found by Cheapflights users on 5/7. 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 7/35:05 amGEG - ONT
1 stop5h 20mDelta
Tue 7/86:30 amONT - GEG
1 stop5h 15mDelta
Deal found 5/7$178
This Delta deal was found by Cheapflights users on 5/7. 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.
Tue 6/245:50 pmPDX - ONT
1 stop4h 56mDelta
Tue 7/15:50 pmONT - PDX
1 stop4h 31mDelta
Deal found 5/7$181
This Alaska Airlines deal was found by Cheapflights users on 5/6. 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.
Sat 8/239:17 pmSEA - ONT
Nonstop2h 42mAlaska Airlines
Sun 8/246:00 amONT - SEA
Nonstop2h 45mAlaska Airlines
Deal found 5/6$187
This Delta deal was found by Cheapflights users on 5/6. 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 8/217:55 pmSEA - ONT
Nonstop2h 46mDelta
Sun 8/247:00 amONT - SEA
Nonstop2h 49mDelta
Deal found 5/6$197

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 May 7, 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

Mon 6/16

10:03 am-12:49 pm

Nonstop2h 46m

$99

PortlandOntario

PDX - ONT

PDXONT

Portland

Fri 5/30

11:04 am-1:24 pm

Nonstop2h 20m

Ontario

Sun 6/1

2:30 pm-4:55 pm

Nonstop2h 25m

$104

PortlandOntario

PDX - ONT

PDXONT

Portland

Tue 9/2

9:30 pm-11:53 pm

Nonstop2h 23m

Ontario

Sun 9/7

8:25 am-10:51 am

Nonstop2h 26m

$142

SpokaneOntario

GEG - ONT

GEGONT

Spokane

Tue 5/20

12:26 pm-11:59 pm

1 stop11h 33m

Ontario

Wed 5/21

12:08 am-11:04 am

1 stop10h 56m

$158

SpokaneOntario

GEG - ONT

GEGONT

Spokane

Wed 9/10

5:46 pm-11:59 pm

1 stop6h 13m

Ontario

Sat 9/27

7:22 pm-11:59 pm

1 stop4h 37m

$168

SpokaneOntario

GEG - ONT

GEGONT

Spokane

Tue 6/3

3:18 pm-9:57 pm

1 stop6h 39m

Ontario

Tue 6/10

6:23 am-1:21 pm

1 stop6h 58m

$169

PortlandOntario

PDX - ONT

PDXONT

Portland

Wed 8/20

7:45 am-12:13 pm

1 stop4h 28m

Ontario

Sat 8/23

1:42 pm-8:37 pm

1 stop6h 55m

$177

SpokaneOntario

GEG - ONT

GEGONT

Spokane

Thu 7/3

5:05 am-10:25 am

1 stop5h 20m

Ontario

Tue 7/8

6:30 am-11:45 am

1 stop5h 15m

$178

PortlandOntario

PDX - ONT

PDXONT

Portland

Tue 6/24

5:50 pm-10:46 pm

1 stop4h 56m

Ontario

Tue 7/1

5:50 pm-10:21 pm

1 stop4h 31m

$181

PascoOntario

PSC - ONT

PSCONT

Pasco Tri Cities

Sat 5/17

1:35 pm-8:34 pm

1 stop6h 59m

Ontario

Mon 5/19

6:00 am-11:32 am

1 stop5h 32m

$199

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/6

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 May 7, 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 May 7, 2025.

The most flights from USWA to ONT are scheduled on a Tuesday (19 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (2 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 May 7, 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
9,994 reviews

Food

7.1

Crew

8.5

Boarding

8.1

Entertainment

7.1

Overall

8.0

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Alaska Airlines
8.0
Very good
9,994 reviews
Alaska Airlines
8.0
Very good
9,994 reviews

Food

7.1

Crew

8.5

Boarding

8.1

Entertainment

7.1

Overall

8.0

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Southwest
8.0
Very good
4,292 reviews
Alaska Airlines
8.0
Very good
9,994 reviews

Food

7.1

Crew

8.5

Boarding

8.1

Entertainment

7.1

Overall

8.0

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Delta
8.0
Very good
7,944 reviews
Alaska Airlines
8.0
Very good
9,994 reviews

Food

7.1

Crew

8.5

Boarding

8.1

Entertainment

7.1

Overall

8.0

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
Hawaiian Airlines
7.9
Good
2,424 reviews
Alaska Airlines
8.0
Very good
9,994 reviews

Food

7.1

Crew

8.5

Boarding

8.1

Entertainment

7.1

Overall

8.0

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.
United Airlines
7.4
Good
8,710 reviews
Alaska Airlines
8.0
Very good
9,994 reviews

Food

7.1

Crew

8.5

Boarding

8.1

Entertainment

7.1

Overall

8.0

Comfort

7.9

Reviews

1 / 20
10.0
Excellent

James,Apr 2025

LAX - SFO

Good flight except the uncontrollable cold air from the ceiling.

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 $57 on Frontier. Other airlines that offer cheap prices include Alaska Airlines from $84 and American Airlines from $85 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 (100%), Korean Air (95%) 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 $54. On average you can expect to pay $371. The most popular route, (Seattle/Tacoma Intl - Ontario), can usually be booked for $71.

  • 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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Alternative routes for Washington to Ontario

See prices for flight routes from nearby airports that may be better suited for you.
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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 May 7, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$40Average$96FlexibilityNo cancel feeOn-time65%
FrontierCheapest$55Average$138FlexibilityNo cancel feeOn-time62%
Hawaiian AirlinesCheapest$97Average$235FlexibilityNo cancel feeOn-time85%
DeltaCheapest$117Average$303FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$136Average$446FlexibilityNo cancel feeOn-time75%
SouthwestCheapest$196Average$356FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$308Average$443FlexibilityNo cancel feeOn-time69%

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