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$97+ 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 9/24. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SEA
Aug 30 — Sep 61
Sun 8/30
Sun 9/6
1 adult, Economy
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Cheap 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 July 31, 2026.

This Frontier deal was found by Cheapflights users on 7/31. 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.
Thu 9/105:44 pm
ONT
-
SEA
Nonstop2h 56m
Frontier
Mon 9/149:45 pm
SEA
-
ONT
1 stop11h 24m
Frontier
Deal found 7/31$197
This Frontier deal was found by Cheapflights users on 7/30. 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.
Thu 9/35:17 pm
ONT
-
SEA
Nonstop2h 45m
Frontier
Tue 9/811:54 am
SEA
-
ONT
Nonstop2h 51m
Frontier
Deal found 7/30$198
This Super.com deal was found by Cheapflights users on 7/30. 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.
Sun 8/164:49 pm
ONT
-
SEA
Nonstop2h 49m
Frontier
Mon 8/178:53 pm
SEA
-
ONT
1 stop19h 01m
Frontier
Deal found 7/30$199
This Frontier deal was found by Cheapflights users on 7/31. 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 8/286:00 am
ONT
-
SEA
1 stop6h 20m
Frontier
Sat 8/2911:54 am
SEA
-
ONT
Nonstop2h 51m
Frontier
Deal found 7/31$200
This Frontier deal was found by Cheapflights users on 7/31. 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 9/66:00 am
ONT
-
SEA
1 stop7h 22m
Frontier
Fri 9/1810:53 am
SEA
-
ONT
Nonstop2h 52m
Frontier
Deal found 7/31$201
This Priceline deal was found by Cheapflights users on 7/30. 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.
Sat 12/510:03 am
ONT
-
SEA
1 stop4h 48m
Multiple Airlines
Mon 12/76:49 pm
SEA
-
ONT
Nonstop2h 48m
Multiple Airlines
Deal found 7/30$202
This FlightHub deal was found by Cheapflights users on 7/30. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/1311:47 am
ONT
-
SEA
1 stop23h 17m
Frontier
Tue 8/1811:54 am
SEA
-
ONT
Nonstop2h 51m
Frontier
Deal found 7/30$203
This FlightHub deal was found by Cheapflights users on 7/30. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/275:17 pm
ONT
-
SEA
Nonstop2h 45m
Frontier
Mon 8/319:29 pm
SEA
-
ONT
1 stop18h 20m
Frontier
Deal found 7/30$204
This Super.com deal was found by Cheapflights users on 7/31. 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 8/104:49 pm
ONT
-
SEA
Nonstop2h 49m
Frontier
Tue 8/1811:54 am
SEA
-
ONT
Nonstop2h 51m
Frontier
Deal found 7/31$205
This Kiwi.com deal was found by Cheapflights users on 7/30. 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.
Tue 9/156:02 am
ONT
-
SEA
Nonstop2h 43m
Multiple Airlines
Fri 9/1810:53 am
SEA
-
ONT
Nonstop2h 52m
Multiple Airlines
Deal found 7/30$206
This Super.com deal was found by Cheapflights users on 7/30. 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 8/104:49 pm
ONT
-
SEA
Nonstop2h 49m
Frontier
Thu 8/2011:54 am
SEA
-
ONT
Nonstop2h 51m
Frontier
Deal found 7/30$207
This Frontier deal was found by Cheapflights users on 7/30. 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 9/66:00 am
ONT
-
SEA
1 stop7h 22m
Frontier
Wed 9/910:53 am
SEA
-
ONT
Nonstop2h 52m
Frontier
Deal found 7/30$208

Find flight deals from Ontario to Washington

Keep the following information in mind while searching for Ontario to Washington flight deals. Data was last updated July 31, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$197
(Frontier)

One-way from

$97
(Kiwi.com)

Popular in

June

Cheapest in

March

Average price

$307

Good round-trip deal

$277 or less

Good one-way deal

$193 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 ($31 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($8 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in July 2026
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 July 31, 2026.
Use the filters below to find and compare flights from Ontario to Washington that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sat 9/12

1:56 pm-8:43 pm

1 stop6h 47m

Seattle/Tacoma Intl

Wed 9/23

3:30 pm-8:01 pm

1 stop4h 31m

$242
Quickest round-trip

OntarioPortland

ONT - PDX

ONTPDX

Ontario

Wed 9/23

10:47 am-1:04 pm

Nonstop2h 17m

Portland

Sat 9/26

2:53 pm-5:18 pm

Nonstop2h 25m

$247

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Wed 8/26

5:00 am-11:44 am

1 stop6h 44m

Seattle/Tacoma Intl

Sun 8/30

7:00 am-12:12 pm

1 stop5h 12m

$247

OntarioPortland

ONT - PDX

ONTPDX

Ontario

Fri 9/25

2:40 pm-7:15 pm

1 stop4h 35m

Portland

Mon 11/2

5:10 am-10:50 am

1 stop5h 40m

$252

OntarioPortland

ONT - PDX

ONTPDX

Ontario

Thu 11/12

11:57 am-6:53 pm

1 stop6h 56m

Portland

Sun 11/15

5:47 pm-11:00 pm

1 stop5h 13m

$257

OntarioSpokane

ONT - GEG

ONTGEG

Ontario

Sat 8/22

7:12 am-11:52 am

1 stop4h 40m

Spokane

Wed 8/26

1:27 pm-7:03 pm

1 stop5h 36m

$257

OntarioSpokane

ONT - GEG

ONTGEG

Ontario

Tue 8/11

9:05 am-4:15 pm

1 stop7h 10m

Spokane

Tue 8/18

5:45 am-10:15 am

1 stop4h 30m

$257

OntarioPortland

ONT - PDX

ONTPDX

Ontario

Mon 8/17

11:56 am-5:14 pm

1 stop5h 18m

Portland

Sat 8/22

5:54 pm-10:45 pm

1 stop4h 51m

$257

OntarioSpokane

ONT - GEG

ONTGEG

Ontario

Sat 8/22

6:10 am-1:00 pm

1 stop6h 50m

Spokane

Mon 8/24

5:10 pm-9:45 pm

1 stop4h 35m

$257

OntarioSpokane

ONT - GEG

ONTGEG

Ontario

Mon 8/17

4:18 pm-9:33 pm

1 stop5h 15m

Spokane

Tue 8/25

7:03 am-2:09 pm

1 stop7h 06m

$257

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/30

Showing 1-10 of 60 resultsSorted by cheapest first
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6

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 $216). Flying from Ontario to State of Washington in July is currently the most expensive (average of $340). 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 July 31, 2026.

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 morning tend to be the most expensive. A flight in the afternoon could potentially save you up to 19% on airfare.

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 July 31, 2026.

The most flights from ONT to USWA are scheduled on a Thursday (25 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (7 on average).

How much does it cost to fly round-trip from Ontario to State of Washington?

Airfare is typical for this route at the moment.
Ontario to State of Washington flights typically cost between $187 and $328 in September.
The cheapest round-trip price found within the last 5 days was $197 on Frontier (Sep 10-Sep 14).

How far ahead should I book a flight from Ontario to State of Washington?

Booking 43 days in advance of your planned departure date is, on average, the best time to get cheap flights from Ontario to State of Washington. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

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 July 25, 2026.

Travelers seeking maximum savings on their Ontario to State of Washington flight should consider departing on Saturday afternoons when fares are most often at their lowest. Saturday evenings flights should be avoided if possible as fares are typically the most expensive at this time.

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 July 31, 2026.
Get a feel of what it's like to fly with Southwest,Alaska Airlines, andDelta 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.
Southwest
8.0
Very good
4,226 reviews

Food

7.0

Crew

8.6

Comfort

8.0

Boarding

8.1

Overall

8.0

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
Southwest
8.0
Very good
4,226 reviews
Southwest
8.0
Very good
4,226 reviews

Food

7.0

Crew

8.6

Comfort

8.0

Boarding

8.1

Overall

8.0

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
Alaska Airlines
7.9
Good
12,738 reviews
Southwest
8.0
Very good
4,226 reviews

Food

7.0

Crew

8.6

Comfort

8.0

Boarding

8.1

Overall

8.0

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
Delta
7.8
Good
8,487 reviews
Southwest
8.0
Very good
4,226 reviews

Food

7.0

Crew

8.6

Comfort

8.0

Boarding

8.1

Overall

8.0

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
Hawaiian Airlines
7.8
Good
2,820 reviews
Southwest
8.0
Very good
4,226 reviews

Food

7.0

Crew

8.6

Comfort

8.0

Boarding

8.1

Overall

8.0

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.
Frontier
5.6
Fair
2,747 reviews
Southwest
8.0
Very good
4,226 reviews

Food

7.0

Crew

8.6

Comfort

8.0

Boarding

8.1

Overall

8.0

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.

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 152 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 $257, United Airlines can have you in State of Washington from Ontario in 4h 40m. Ontario and State of Washington are separated by a distance of 936 mi. This flight may include one or multiple stops.

  • 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 $57. Users have also found prices from $75 and $87 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: Japan Airlines (98%), Korean Air (95%), Scandinavian Airlines( 94%).

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

    Looking at all options, your cheapest flight can be booked for $83. While the most popular route (Ontario - Seattle/Tacoma Intl) can be booked for $92 on average, our data indicates $803 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 $216). Flying from Ontario to State of Washington in July is currently the most expensive (average of $340). 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

See prices for flight routes from nearby airports that may be better suited for you.
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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 July 31, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$84Average$221FlexibilityNo cancel feeOn-time62%
Hawaiian AirlinesCheapest$98Average$209FlexibilityNo cancel feeOn-time85%
DeltaCheapest$101Average$317FlexibilityNo cancel feeOn-timeN/A
Alaska AirlinesCheapest$139Average$425FlexibilityNo cancel feeOn-time75%
SouthwestCheapest$150Average$339FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$176Average$378FlexibilityNo cancel feeOn-time69%

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