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$64+ 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 1/24. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — ONT
Jan 25 — Feb 11
Sun 1/25
Sun 2/1
1 adult, Economy
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Cheap 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 December 26, 2025.

This Mytrip deal was found by Cheapflights users on 12/24. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/311:25 pmSEA - ONT
1 stop10h 34mFrontier
Wed 1/710:45 amONT - SEA
1 stop22h 19mFrontier
Deal found 12/24$225
This Super.com deal was found by Cheapflights users on 12/24. 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.
Mon 12/2911:06 amSEA - ONT
Nonstop2h 36mFrontier
Sun 1/115:15 pmONT - SEA
Nonstop2h 53mFrontier
Deal found 12/24$235
This Frontier deal was found by Cheapflights users on 12/24. 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 12/311:25 pmSEA - ONT
1 stop10h 34mFrontier
Mon 1/52:45 pmONT - SEA
Nonstop2h 53mFrontier
Deal found 12/24$265
This Frontier deal was found by Cheapflights users on 12/24. 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 12/2812:47 pmPDX - ONT
1 stop11h 12mFrontier
Thu 1/810:18 pmONT - PDX
1 stop11h 16mFrontier
Deal found 12/24$292
This Frontier deal was found by Cheapflights users on 12/25. 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 12/312:46 pmSEA - ONT
1 stop6h 31mFrontier
Mon 1/122:34 pmONT - SEA
1 stop5h 13mFrontier
Deal found 12/25$302
This Frontier deal was found by Cheapflights users on 12/24. 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 12/311:25 pmSEA - ONT
1 stop10h 34mFrontier
Tue 1/67:52 amONT - SEA
1 stop9h 59mFrontier
Deal found 12/24$312
This CheapOair deal was found by Cheapflights users on 12/24. 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 12/2512:47 pmPDX - ONT
1 stop11h 12mFrontier
Tue 12/306:00 amONT - PDX
1 stop7h 24mFrontier
Deal found 12/24$313
This Frontier deal was found by Cheapflights users on 12/24. 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 12/311:25 pmSEA - ONT
1 stop10h 34mFrontier
Sat 1/33:50 pmONT - SEA
Nonstop2h 53mFrontier
Deal found 12/24$314
This CheapOair deal was found by Cheapflights users on 12/25. 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.
Sun 12/2811:06 amSEA - ONT
Nonstop2h 36mFrontier
Fri 1/92:34 pmONT - SEA
1 stop18h 30mFrontier
Deal found 12/25$316
This Frontier deal was found by Cheapflights users on 12/24. 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 12/2712:37 pmPDX - ONT
1 stop11h 22mFrontier
Thu 1/810:18 pmONT - PDX
1 stop11h 16mFrontier
Deal found 12/24$317
This CheapOair deal was found by Cheapflights users on 12/24. 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.
Sun 12/2812:47 pmPDX - ONT
1 stop11h 12mFrontier
Wed 1/77:00 amONT - PDX
1 stop28h 15mFrontier
Deal found 12/24$318
This Priceline deal was found by Cheapflights users on 12/23. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/3011:06 amSEA - ONT
Nonstop2h 36mFrontier
Tue 1/67:52 amONT - SEA
1 stop9h 59mFrontier
Deal found 12/23$324

Find flight deals from Washington to Ontario

Keep the following information in mind while searching for Washington to Ontario flight deals. Data was last updated December 26, 2025.

Most accurate provider

CheapOair
3 stars

Most trusted provider

CheapOair
3 stars

Round-trip from

$121
(Frontier)

One-way from

$64
(Cheapflightsfares)

Popular in

December

Cheapest in

January

Average price

$298

Good round-trip deal

$207 or less

Good one-way deal

$120 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. 5% potential increase in price ($14 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($7 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 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

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 December 26, 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

Tue 3/3

8:05 pm-10:44 pm

Nonstop2h 39m

Ontario

Sat 3/7

4:02 pm-6:52 pm

Nonstop2h 50m

$128

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Wed 2/11

5:30 am-12:16 pm

1 stop6h 46m

Ontario

Sun 2/15

7:30 am-10:34 am

Nonstop3h 04m

$129

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Mon 2/9

7:00 pm-11:58 pm

1 stop4h 58m

Ontario

Sat 2/14

3:30 pm-6:33 pm

Nonstop3h 03m

$129

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Sat 3/14

2:30 pm-5:12 pm

Nonstop2h 42m

Ontario

Mon 3/16

5:09 pm-12:03 am

1 stop6h 54m

$129

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Sat 3/7

8:56 pm-11:32 pm

Nonstop2h 36m

Ontario

Mon 3/16

6:14 am-9:09 am

Nonstop2h 55m

$139

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Sat 2/7

5:00 am-12:16 pm

1 stop7h 16m

Ontario

Wed 2/18

5:00 pm-12:09 am

1 stop7h 09m

$139

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Wed 2/11

7:00 pm-11:58 pm

1 stop4h 58m

Ontario

Tue 2/17

5:00 pm-12:09 am

1 stop7h 09m

$139

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Sat 2/7

5:00 am-12:16 pm

1 stop7h 16m

Ontario

Tue 2/17

5:00 pm-12:09 am

1 stop7h 09m

$139

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Tue 2/10

5:30 am-12:16 pm

1 stop6h 46m

Ontario

Tue 2/17

5:00 pm-12:09 am

1 stop7h 09m

$139

SeattleOntario

SEA - ONT

SEAONT

Seattle/Tacoma Intl

Sat 2/7

5:00 am-12:16 pm

1 stop7h 16m

Ontario

Thu 2/12

1:10 pm-6:29 pm

1 stop5h 19m

$139

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/24

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, January is the cheapest month in which you can book a flight from State of Washington to Ontario (average of $38). Flying from State of Washington to Ontario in November is currently the most expensive (average of $108). 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 December 26, 2025.

A simple way to save on the total cost of your ticket is to fly from State of Washington to Ontario in the evening. If you’re flexible enough to do this you can expect to save up to 37% on your trip compared to booking a flight in the morning.

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

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

Travelers seeking maximum savings on their State of Washington to Ontario flight should consider departing on Thursday at noon 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 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 December 26, 2025.

The most flights from USWA to ONT are scheduled on a Friday (21 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (11 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 51 times in the past calendar month.

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

    Airlines like Alaska Airlines and Delta fly from State of Washington to Ontario in about 2h 39m. The time it takes to get you to your destination can typically vary by up to 4h 07m. 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 $46 on Frontier. Other airlines that offer cheap prices include Southwest from $62 and Hawaiian Airlines from $78 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 Virgin Atlantic (97%), KLM (94%) and Korean Air (94%).

  • 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 $333. The most popular route, (Seattle/Tacoma Intl - Ontario), can usually be booked for $99.

  • 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, January is the cheapest month in which you can book a flight from State of Washington to Ontario (average of $38). Flying from State of Washington to Ontario in November is currently the most expensive (average of $108). 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 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 December 26, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$68Average$175FlexibilityNo cancel feeOn-time62%
Hawaiian AirlinesCheapest$98Average$237FlexibilityNo cancel feeOn-time85%
DeltaCheapest$118Average$290FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$129Average$342FlexibilityNo cancel feeOn-time75%
SouthwestCheapest$130Average$288FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$158Average$332FlexibilityNo cancel feeOn-time69%

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