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Ontario

$34+ Cheap flights from Ontario

ONT — SFO
Oct 17 — Oct 241
Sat 10/17
Sat 10/24
1 adult, Economy
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Find flights from Ontario within your budget

 

Fly to

Route

Depart

Return

Price

Cheapest round-trip
Quickest round-trip

OntarioSan Francisco

ONT Ontario - SFO San Francisco

ONTSFO

Ontario

Wed 10/28

1:35 pm-3:05 pm

Nonstop1h 30m

San Francisco

Wed 12/31

12:00 am-12:00 am

Nonstop0h 00m

$114

OntarioLas Vegas

ONT Ontario - LAS Las Vegas Harry Reid Intl

ONTLAS

Ontario

Sat 11/14

1:10 pm-7:10 pm

2 stops6h 00m

Las Vegas Harry Reid Intl

Wed 12/31

12:00 am-12:00 am

Nonstop0h 00m

$120

OntarioChicago

ONT Ontario - ORD Chicago O'Hare Intl

ONTORD

Ontario

Sat 11/14

5:59 pm-9:04 am

2 stops13h 05m

Chicago O'Hare Intl

Wed 12/31

12:00 am-10:00 pm

Nonstop0h 00m

$124

OntarioLas Vegas

ONT Ontario - LAS Las Vegas Harry Reid Intl

ONTLAS

Ontario

Mon 12/14

11:20 am-6:34 pm

1 stop7h 14m

Las Vegas Harry Reid Intl

Wed 12/31

12:00 am-12:00 am

Nonstop0h 00m

$124

OntarioSeattle

ONT Ontario - SEA Seattle/Tacoma Intl

ONTSEA

Ontario

Tue 10/6

10:55 am-6:45 pm

1 stop7h 50m

Seattle/Tacoma Intl

Wed 12/31

12:00 am-12:00 am

Nonstop0h 00m

$129

OntarioDenver

ONT Ontario - DEN Denver Intl

ONTDEN

Ontario

Mon 11/9

8:35 pm-6:10 pm

1 stop20h 35m

Denver Intl

Wed 12/31

12:00 am-11:00 pm

Nonstop0h 00m

$131

OntarioSan Francisco

ONT Ontario - SFO San Francisco

ONTSFO

Ontario

Wed 11/11

9:25 am-10:55 am

Nonstop1h 30m

San Francisco

Wed 12/31

12:00 am-12:00 am

Nonstop0h 00m

$131

OntarioSan Francisco

ONT Ontario - SFO San Francisco

ONTSFO

Ontario

Wed 10/7

4:03 pm-5:50 pm

Nonstop1h 47m

San Francisco

Wed 12/31

12:00 am-12:00 am

Nonstop0h 00m

$131

OntarioSeattle

ONT Ontario - SEA Seattle/Tacoma Intl

ONTSEA

Ontario

Sat 11/14

1:25 pm-9:55 pm

1 stop8h 30m

Seattle/Tacoma Intl

Wed 12/31

12:00 am-12:00 am

Nonstop0h 00m

$134

OntarioLas Vegas

ONT Ontario - LAS Las Vegas Harry Reid Intl

ONTLAS

Ontario

Sun 10/4

1:04 pm-6:20 pm

1 stop5h 16m

Las Vegas Harry Reid Intl

Wed 12/31

12:00 am-12:00 am

Nonstop0h 00m

$135

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/16

Showing 1-10 of 60 resultsSorted by cheapest first
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Compare providers for flights from Ontario

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Ontario in September
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
JustAirTicketPrice Accuracy-Trust Score*1 star
CheapfaremartPrice Accuracy-Trust Score*1 star
Super.comPrice Accuracy-Trust Score*3 stars
CheapOairPrice Accuracy3 starsTrust Score*3 stars
Kiwi.comPrice Accuracy3 starsTrust Score*3 stars
eDreamsPrice Accuracy2 starsTrust Score*3 stars
CheapTicketsDealPrice Accuracy1 starTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: Among all the travel providers offering deals on flights from Ontario, FlightHub has been found to have the most accurate pricing. Users can find the same prices on deals on Cheapflights as FlightHub about >95% of the time. This is based on searches for flights from Ontario made on Cheapflights over the past month and is updated monthly.
  • Most trusted provider: In terms of trustworthiness, Cheapflights users rate FlightHub the highest out of those offering flight deals from Ontario. FlightHub has a user feedback rating of 3 out of 3 stars (3 being the best) and has received the most positive sentiment from Cheapflights users searching for flights from Ontario. This info is gathered from Cheapflights searches over the past month.

Ontario travel tips

  • 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

Travel insights for flights from Ontario

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

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

Currently, October is the cheapest month in which you can book a flight from Ontario (average of $138). Flying from Ontario in February will prove the most costly (average of $307). There are multiple factors that influence the price of a flight so comparing airlines, departure airports and times can help keep costs down.

Which airlines fly from Ontario?

For flights departing from Ontario check dates and pricing for the following: United Airlines, Frontier, Alaska Airlines, JetBlue, Southwest. These airlines depart to the following popular destinations: San Francisco.

Frontier
Frontier
From $29
Southwest
Southwest
From $117
American Airlines
American Airlines
From $151
United Airlines
United Airlines
From $100

What are popular destinations to fly to from Ontario?

Some of the most frequent flights departing from Ontario everyday are: Dallas (113 flights per day), Seattle (94 flights per day), and Atlanta (69 flights per day).

Taipei City Taiwan Taoyuan Intl
Taipei City Taiwan Taoyuan Intl
From $402
Denver Intl
Denver Intl
From $120
Dallas/Fort Worth
Dallas/Fort Worth
From $126
San Francisco
San Francisco
From $30

What is the cheapest place to fly to from Ontario?

The cheapest city to fly to from Ontario is San Francisco, with prices starting at $30. Explore other affordable destinations below.

San Francisco
San Francisco
From $30
San Jose
San Jose
From $58
Las Vegas Harry Reid Intl
Las Vegas Harry Reid Intl
From $60
Seattle/Tacoma Intl
Seattle/Tacoma Intl
From $64

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

To ensure you get the cheapest price possible for a flight from Ontario, you should look to book at least 72 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.

When is the cheapest time to fly from Ontario?

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

Airline reviews for flights from Ontario

Peruse reviews from past customers who have flown Southwest,Alaska Airlines, andUnited Airlines from Ontario to help guide your decision. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,190 reviews

Crew

8.6

Overall

8.0

Food

7.0

Comfort

8.0

Boarding

8.1

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Southwest
8.0
Very good
4,190 reviews
Southwest
8.0
Very good
4,190 reviews

Crew

8.6

Overall

8.0

Food

7.0

Comfort

8.0

Boarding

8.1

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Alaska Airlines
7.9
Good
12,937 reviews
Southwest
8.0
Very good
4,190 reviews

Crew

8.6

Overall

8.0

Food

7.0

Comfort

8.0

Boarding

8.1

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
United Airlines
7.4
Good
10,214 reviews
Southwest
8.0
Very good
4,190 reviews

Crew

8.6

Overall

8.0

Food

7.0

Comfort

8.0

Boarding

8.1

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
JetBlue
7.1
Good
3,035 reviews
Southwest
8.0
Very good
4,190 reviews

Crew

8.6

Overall

8.0

Food

7.0

Comfort

8.0

Boarding

8.1

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.
Frontier
5.6
Fair
2,599 reviews
Southwest
8.0
Very good
4,190 reviews

Crew

8.6

Overall

8.0

Food

7.0

Comfort

8.0

Boarding

8.1

Entertainment

7.5

Reviews

1 / 20
8.0
Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.

Browse thousands of different options on Cheapflights for your next trip

Popular international destinations from Ontario

Flights from Ontario to Guadalajara
Flights from Ontario to San Salvador
Flights from Ontario to Morelia
Flights from Ontario to León

Related info for your journey

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

    This month, the top selected destinations from Ontario are Las Vegas, Dallas/Fort Worth Airport, Denver. Throughout the year, Las Vegas, Dallas/Fort Worth Airport, 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 San Francisco (prices may vary depending on the airline and departure time). On average, users have booked flights for $595 to fly from Ontario.

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

    Over the past few days, we've found that Frontier, Alaska Airlines, and Hawaiian Airlines have the cheapest prices from Ontario. Frontier flights from Ontario to Atlanta Hartsfield-Jackson ($29), Alaska Airlines flights from Ontario to Anchorage ($78), and Hawaiian Airlines flights from Ontario to Honolulu ($88).

  • 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 Denver starting at $489
    Fly from Ontario to Las Vegas starting at $526
    Fly from Ontario to Guadalajara starting at $678
    Fly from Ontario to Portland starting at $955

  • 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 $213 so you can fly first-class even on a budget.

  • What is the cheapest month to fly from Ontario?

    October is currently the cheapest month to fly from Ontario. At this moment in time February 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 $75 round trip
    Fly from Ontario to San Francisco from $118 round trip
    Fly from Ontario to Minneapolis from $128 round trip
    Fly from Ontario to Seattle from $134 round trip
    Fly from Ontario to Phoenix from $159 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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