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Ontario

$29+ Cheap flights from Ontario

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 10/23. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — SEA
Oct 17 — Oct 241
Fri 10/17
Fri 10/24
1 adult, Economy
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What to know about flights from Ontario

Discover essential information about flights departing from Ontario, including flight schedules, destinations, airlines operating at the Ontario airport, and any specific guidelines or requirements for travelers. Please note that the information is based on the most recent updates available. Data last updated September 17, 2025.

Cheapest one-way flight

$33

Cheapest round-trip flight

$48

Cheapest airline

LEVEL

Most popular destination

New York John F Kennedy Intl (JFK)

Good round-trip deal

$99 or less

Good one-way deal

$43 or less
The cheapest one-way flight from Ontario is currently to Las Vegas Harry Reid Intl.
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The cheapest round-trip flight from Ontario is currently to Las Vegas Harry Reid Intl.
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On average, LEVEL currently has the cheapest one-way flight from Ontario (avg. price of $645).
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New York John F Kennedy Intl (JFK) is currently the most popular flight destination from Ontario (average round-trip price of $792).
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Price to beat on a round-trip flight from Ontario.
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Price to beat on a one-way flight from Ontario.
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Find flights from Ontario

Cheapest flights from Ontario
Explore the most affordable flight options available from Ontario. Find the lowest fares based on data from user searches, with prices last updated on September 17, 2025.

This Cheapflightsfares deal was found by Cheapflights users on 9/17. 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.
Thu 10/29:16 amONT - LAS
Nonstop1h 08mFrontier
Sat 10/48:49 pmLAS - ONT
Nonstop1h 07mFrontier
Deal found 9/17$58
This Frontier deal was found by Cheapflights users on 9/16. 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 10/310:28 pmONT - LAS
Nonstop1h 16mFrontier
Sat 10/411:27 amLAS - ONT
Nonstop1h 16mFrontier
Deal found 9/16$59
This Cheapflightsfares deal was found by Cheapflights users on 9/14. 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.
Thu 10/26:00 amONT - LAS
Nonstop1h 11mFrontier
Tue 10/77:33 pmLAS - ONT
Nonstop1h 09mFrontier
Deal found 9/14$62
This Cheapflightsfares deal was found by Cheapflights users on 9/17. 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.
Sun 9/286:00 amONT - LAS
Nonstop1h 11mFrontier
Wed 10/18:49 pmLAS - ONT
Nonstop1h 07mFrontier
Deal found 9/17$63
This Cheapflightsfares deal was found by Cheapflights users on 9/15. 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.
Sat 9/278:00 amONT - LAS
Nonstop1h 11mFrontier
Wed 10/297:33 pmLAS - ONT
Nonstop1h 09mFrontier
Deal found 9/15$65
This Cheapflightsfares deal was found by Cheapflights users on 9/15. 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 10/106:53 amONT - DEN
Nonstop2h 25mFrontier
Mon 10/1310:29 pmDEN - ONT
Nonstop2h 21mFrontier
Deal found 9/15$67
This Cheapflightsfares deal was found by Cheapflights users on 9/16. 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.
Thu 10/96:05 amONT - LAS
Nonstop1h 11mFrontier
Sat 10/117:33 pmLAS - ONT
Nonstop1h 09mFrontier
Deal found 9/16$68
This Mytrip deal was found by Cheapflights users on 9/16. 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.
Tue 10/147:04 amONT - DEN
Nonstop2h 27mFrontier
Wed 10/2210:29 pmDEN - ONT
Nonstop2h 21mFrontier
Deal found 9/16$68
This Frontier deal was found by Cheapflights users on 9/17. 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 10/88:00 amONT - LAS
Nonstop1h 12mFrontier
Thu 10/910:37 amLAS - ONT
Nonstop1h 10mFrontier
Deal found 9/17$69
This Cheapflightsfares deal was found by Cheapflights users on 9/16. 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.
Sat 9/278:00 amONT - LAS
Nonstop1h 11mFrontier
Sat 9/2711:27 amLAS - ONT
Nonstop1h 16mFrontier
Deal found 9/16$72
This Cheapflightsfares deal was found by Cheapflights users on 9/15. 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.
Thu 10/29:46 pmONT - SFO
Nonstop1h 29mFrontier
Fri 10/310:11 pmSFO - ONT
Nonstop1h 27mFrontier
Deal found 9/15$72
This Frontier deal was found by Cheapflights users on 9/14. 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.
Mon 9/296:00 amONT - LAS
Nonstop1h 11mFrontier
Fri 10/36:10 amLAS - ONT
Nonstop1h 07mFrontier
Deal found 9/14$73

Find flights from Ontario within your budget

 
Find flights departing from Ontario that match your specified budget. Filter results by price range, allowing you to narrow down options and find flights that fit within your financial constraints. Please note that the search results are based on data from user searches, with fares last updated on September 17, 2025. In the last 7 days, Cheapflights users made a total of 2,558,603 searches

Fly to

Seattle

Route

Depart

Return

Price

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Sat 10/11

8:45 pm-9:50 pm

Nonstop1h 05m

Las Vegas Harry Reid Intl

Tue 10/14

7:20 am-8:25 am

Nonstop1h 05m

$77

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Sun 10/26

9:05 pm-10:10 pm

Nonstop1h 05m

Las Vegas Harry Reid Intl

Tue 10/28

7:20 am-8:25 am

Nonstop1h 05m

$77

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Thu 12/4

8:55 pm-9:55 pm

Nonstop1h 00m

Las Vegas Harry Reid Intl

Sat 12/6

5:55 am-11:10 am

1 stop5h 15m

$87

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Tue 11/18

8:55 pm-9:55 pm

Nonstop1h 00m

Las Vegas Harry Reid Intl

Thu 11/20

2:15 pm-3:20 pm

Nonstop1h 05m

$87

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Thu 11/13

9:15 pm-10:15 pm

Nonstop1h 00m

Las Vegas Harry Reid Intl

Sat 11/15

2:20 pm-3:25 pm

Nonstop1h 05m

$87

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Wed 10/15

9:10 pm-10:15 pm

Nonstop1h 05m

Las Vegas Harry Reid Intl

Wed 10/22

8:20 pm-9:25 pm

Nonstop1h 05m

$87

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Mon 11/10

9:15 pm-10:15 pm

Nonstop1h 00m

Las Vegas Harry Reid Intl

Wed 11/12

8:35 am-9:35 am

Nonstop1h 00m

$87

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Fri 11/7

9:15 pm-10:15 pm

Nonstop1h 00m

Las Vegas Harry Reid Intl

Sat 11/8

8:40 am-9:40 am

Nonstop1h 00m

$87

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Tue 12/2

8:55 pm-9:55 pm

Nonstop1h 00m

Las Vegas Harry Reid Intl

Thu 12/4

5:10 pm-6:15 pm

Nonstop1h 05m

$97

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sat 10/18

7:35 am-10:35 am

Nonstop3h 00m

Seattle/Tacoma Intl

Fri 10/24

7:55 pm-10:41 pm

Nonstop2h 46m

$133

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/14

Showing 1-10 of 60 results
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Ontario travel tips

Get helpful tips and advice for traveling to or from Ontario. Find recommendations for transportation, accommodations, local attractions, dining options, and other practical tips to enhance your travel experience. Please note that the travel tips are based on general knowledge and recommendations. Data last updated September 17, 2025.
  • If you are a member of the military, you can always go to the USO Lounge at Ontario International Airport (ONT), which provides free drinks, snacks, and access to high-speed Wi-Fi. It can be found directly across from Parking Lot F.
  • Parents will want to take note of the nursing rooms that are scattered throughout Ontario International Airport (ONT). These rooms provide parents with a comfortable place to tend to their children and contain amenities like padded benches, changing tables, and outlets.
  • Ontario International Airport (ONT) has several dining options to choose from, including a few fast-food restaurants, and sit-down restaurants that serve cuisines like American and Italian.

Best time to book a flight from Ontario

Have a flexible travel schedule? Discover the best time to fly 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.

Travel insights for flights from Ontario

Get recent, data-driven insights about flights from Ontario including ideal travel times, pricing trends, and more.

When is the best time to book a flight from Ontario?

Use this chart to determine the optimal time to book a round-trip flight from Ontario to Seattle. Price data was last updated on September 12, 2025.

To ensure you get the cheapest price possible for a flight from Ontario, you should look to book at least 90 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

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

Currently, January is the cheapest month in which you can book a flight from Ontario (average of $38). Flying from Ontario in July will prove the most costly (average of $134). There are multiple factors that influence the price of a flight so comparing airlines, departure airports and times can help keep costs down.

When is the cheapest time to fly from Ontario?

Use this chart to determine the cheapest time to fly round-trip from Ontario to Seattle. Price data was last updated on September 14, 2025.

Those who are seeking the cheapest fare on flights departing from Ontario would be wise to consider leaving during Friday mornings when prices are typically at their lowest. When considering other options, price-conscious travelers should avoid Sunday at noon when fares are usually the most expensive.

Which airlines fly from Ontario?

For flights departing from Ontario check dates and pricing for the following: Frontier, Alaska Airlines, Delta, Hawaiian Airlines, Southwest. These airlines depart to the following popular destinations: Seattle.

Frontier
Frontier
From $36
American Airlines
American Airlines
From $124
Southwest
Southwest
From $97
China Airlines
China Airlines
From $602

What are popular destinations to fly to from Ontario?

Some of the most frequent flights departing from Ontario everyday are: Seattle (116 flights per day), Atlanta (88 flights per day), and Dallas (86 flights per day).

Las Vegas Harry Reid Intl
Las Vegas Harry Reid Intl
From $30
Denver Intl
Denver Intl
From $76
Dallas/Fort Worth
Dallas/Fort Worth
From $69
Taipei City Taiwan Taoyuan Intl
Taipei City Taiwan Taoyuan Intl
From $385

What is the cheapest place to fly to from Ontario?

The cheapest city to fly to from Ontario is Las Vegas Harry Reid Intl, with prices starting at $30. Explore other affordable destinations below.

Las Vegas Harry Reid Intl
Las Vegas Harry Reid Intl
From $30
Portland
Portland
From $32
Oakland
Oakland
From $38
San José del Cabo Los Cabos
San José del Cabo Los Cabos
From $38

Airline reviews for flights from Ontario

Read reviews and ratings of airlines operating flights from Ontario. Gain insights into the quality of service, in-flight amenities, customer experiences, and overall satisfaction to choose the best airline for your Ontario travel. Please note that the reviews are sourced from user searches and were last updated on September 17, 2025. In the last 7 days, Cheapflights users made a total of 2,558,603 searches.
Peruse reviews from past customers who have flown Alaska Airlines, Southwest, and Delta from Ontario to help guide your decision. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Overall

8.0

Boarding

8.1

Comfort

7.8

Crew

8.5

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why
Alaska Airlines
8.0
Very good
10,000 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Overall

8.0

Boarding

8.1

Comfort

7.8

Crew

8.5

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why
Southwest
8.0
Very good
4,242 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Overall

8.0

Boarding

8.1

Comfort

7.8

Crew

8.5

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why
Delta
8.0
Very good
7,961 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Overall

8.0

Boarding

8.1

Comfort

7.8

Crew

8.5

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why
Hawaiian Airlines
7.8
Good
2,729 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Overall

8.0

Boarding

8.1

Comfort

7.8

Crew

8.5

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why
Frontier
5.8
Fair
3,173 reviews
Alaska Airlines
8.0
Very good
10,000 reviews

Entertainment

7.1

Overall

8.0

Boarding

8.1

Comfort

7.8

Crew

8.5

Food

7.1

Reviews

1 / 20
10.0
Excellent

Anonymous,Aug 2025

MFR - SEA

Great smooth flight. Was hour and half late though. Don't know why

Browse thousands of different options on Cheapflights for your next trip

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Popular international destinations from Ontario

The most popular international flight routes departing from Ontario we’ve come across at this time.
Flights from Ontario to Guadalajara
Flights from Ontario to San José del Cabo
Flights from Ontario to San Salvador
Flights from Ontario to Morelia
Flights from Ontario to León

Related info for your journey

Access useful and relevant information related to your journey from Ontario. This can include details such as airport transportation, visa requirements, travel insurance, luggage regulations, and any other information that can ensure a smooth and hassle-free travel experience. Please note that the information is based on general guidance and may need to be verified with official sources. Data last updated September 17, 2025.

  • What are the most popular destinations to fly to from Ontario?

    This month, the top selected destinations from Ontario are Denver, Dallas/Fort Worth Airport, Honolulu. Throughout the year, Dallas/Fort Worth Airport, Denver, Guadalajara are some of the top choices made by users flying from Ontario.

  • What is the cheapest flight from Ontario to anywhere?

    Users have flown out of Ontario for as low as $30 to Las Vegas (prices may vary depending on the airline and departure time). On average, users have booked flights for $477 to fly from Ontario.

  • What are the cheapest airlines flying from Ontario to anywhere?

    Over the past few days, we've found that Spirit Airlines, Frontier, and United Airlines have the cheapest prices from Ontario. Spirit Airlines flights from Ontario to Atlanta Hartsfield-Jackson ($22), Frontier flights from Ontario to Denver Arapahoe Co ($36), and United Airlines flights from Ontario to Abuja ($58).

  • What is the cheapest premium economy flight from Ontario?

    Options for some of the cheapest premium economy flights from Ontario we have found on Cheapflights are as follows:
    Fly from Ontario to Las Vegas starting at $73
    Fly from Ontario to Guadalajara starting at $433
    Fly from Ontario to Salt Lake City starting at $631
    Fly from Ontario to Portland starting at $702

  • What is the cheapest first class flight from Ontario?

    If you’re looking for a cheap first-class flight from Ontario, consider Las Vegas. Prices start at $58 so you can fly first-class even on a budget.

  • What is the cheapest month to fly from Ontario?

    January is currently the cheapest month to fly from Ontario. At this moment in time July is the most expensive month. These prices are determined by multiple factors and booking in advance can help keep costs down if your schedule is not as flexible.

  • Where are the cheapest places to fly to from Ontario?

    Check out the cheapest flights from Ontario to embark to:
    Fly from Ontario to Las Vegas from $39 round trip
    Fly from Ontario to San Francisco from $53 round trip
    Fly from Ontario to Denver from $67 round trip
    Fly from Ontario to Dallas from $93 round trip
    Fly from Ontario to Houston from $93 round trip

  • What parking options are available at Ontario International Airport (ONT)?

    There are a few parking options available at Ontario International Airport (ONT), including over five different lots that provide short and long-term parking. You can also opt for premium parking, which will put you closer to your terminal.

  • How can I go from downtown Ontario to Ontario International Airport (ONT)?

    If you drive from downtown Ontario to Ontario International Airport (ONT), it will take around 5 to 10 minutes. With public transportation, like bus line 61, it will take you around 30 to 35 minutes instead.

  • Is there a hotel located directly at Ontario International Airport (ONT)?

    Ontario International Airport (ONT) does not have its own on-site hotel, but there are quite a few that are just a short distance from the transportation hub. The DoubleTree by Hilton Hotel Ontario Airport has a free shuttle and is less than a 15-minute drive away.

  • Does Ontario International Airport (ONT) have any pet relief areas?

    Ontario International Airport (ONT) has pet relief areas that are both indoors and outdoors. Indoor areas can be found in Terminals 2 and 4, while outdoor areas are located at the far end of each terminal building.

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