$43+ 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 23/10. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
ONT — SYD
17 Oct — 24 Oct1
1 adult
1 adult, Economy

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 travellers. Please note that the information is based on the most recent updates available. Data last updated 17 September 2025.

Cheapest one-way flight

$45

Cheapest round-trip flight

$70

Cheapest airline

Alaska Airlines

Most popular destination

Sydney Kingsford Smith (SYD)

Good round-trip deal

$1,638 or less

Good one-way deal

$330 or less
The cheapest one-way flight from Ontario is currently to Las Vegas Harry Reid Intl.
The cheapest round-trip flight from Ontario is currently to Las Vegas Harry Reid Intl.
On average, Alaska Airlines currently has the cheapest one-way flight from Ontario (avg. price of $207).
Sydney Kingsford Smith (SYD) is currently the most popular flight destination from Ontario (average return price of $900).
Price to beat on a round-trip flight from Ontario.
Price to beat on a one-way flight from Ontario.

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 17 September 2025.

Sat 11/1020:45ONT - LAS
Nonstop1h 05mSouthwest
Mon 13/1022:00LAS - ONT
Nonstop1h 00mSouthwest
Deal found 16/9$115
Wed 15/1021:10ONT - LAS
Nonstop1h 05mSouthwest
Wed 22/1020:20LAS - ONT
Nonstop1h 05mSouthwest
Deal found 16/9$130
Fri 17/1021:35ONT - LAS
Nonstop1h 05mSouthwest
Tue 21/1007:25LAS - ONT
2 stops5h 30mSouthwest
Deal found 14/9$138
Tue 14/1021:10ONT - LAS
Nonstop1h 05mSouthwest
Tue 21/1007:25LAS - ONT
2 stops5h 30mSouthwest
Deal found 16/9$153
Tue 2/1218:30ONT - LAS
1 stop4h 35mSouthwest
Thu 4/1214:15LAS - ONT
Nonstop1h 05mSouthwest
Deal found 14/9$160
Tue 14/1007:00ONT - LAS
2 stops5h 20mSouthwest
Tue 14/1014:35LAS - ONT
Nonstop1h 00mSouthwest
Deal found 14/9$168
Tue 28/1006:53ONT - LAS
1 stop8h 53mFrontier
Tue 28/1019:33LAS - ONT
Nonstop1h 09mFrontier
Deal found 15/9$169
Fri 17/1021:35ONT - LAS
Nonstop1h 05mSouthwest
Mon 20/1022:00LAS - ONT
Nonstop1h 00mSouthwest
Deal found 14/9$171
Tue 4/1116:35ONT - PDX
1 stop6h 07mDelta
Sat 15/1117:26PDX - ONT
1 stop5h 29mDelta
Deal found 16/9$226
Tue 30/1217:20ONT - PDX
1 stop4h 35mSouthwest
Wed 7/105:05PDX - ONT
2 stops7h 20mSouthwest
Deal found 16/9$234
Tue 28/1007:35ONT - PDX
1 stop7h 03mDelta
Tue 4/1117:00PDX - ONT
1 stop4h 20mDelta
Deal found 15/9$235
Sun 5/1008:07ONT - PDX
Nonstop2h 26mFrontier
Mon 6/1011:23PDX - ONT
1 stop9h 33mFrontier
Deal found 15/9$238

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 17 September 2025. In the last 7 days, Cheapflights users made a total of 647,157 searches

Fly to

Sydney

Route

Depart

Return

Price

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Sat 11/10

20:45-21:50

Nonstop1h 05m

Las Vegas Harry Reid Intl

Mon 13/10

22:00-23:00

Nonstop1h 00m

$115

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Sat 11/10

20:45-21:50

Nonstop1h 05m

Las Vegas Harry Reid Intl

Tue 14/10

07:20-08:25

Nonstop1h 05m

$115

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Fri 24/10

21:35-22:40

Nonstop1h 05m

Las Vegas Harry Reid Intl

Mon 27/10

22:00-23:00

Nonstop1h 00m

$115

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Sun 26/10

21:05-22:10

Nonstop1h 05m

Las Vegas Harry Reid Intl

Tue 28/10

07:20-08:25

Nonstop1h 05m

$115

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Thu 4/12

20:55-21:55

Nonstop1h 00m

Las Vegas Harry Reid Intl

Sat 6/12

05:55-11:10

1 stop5h 15m

$130

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Fri 7/11

21:15-22:15

Nonstop1h 00m

Las Vegas Harry Reid Intl

Sat 8/11

07:20-13:30

1 stop6h 10m

$145

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Tue 18/11

20:55-21:55

Nonstop1h 00m

Las Vegas Harry Reid Intl

Wed 19/11

07:00-10:35

1 stop3h 35m

$145

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Tue 2/12

20:55-21:55

Nonstop1h 00m

Las Vegas Harry Reid Intl

Thu 4/12

17:10-18:15

Nonstop1h 05m

$145

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Wed 15/10

21:10-22:15

Nonstop1h 05m

Las Vegas Harry Reid Intl

Wed 22/10

05:25-09:55

1 stop4h 30m

$145

OntarioLas Vegas

ONT - LAS

ONTLAS

Ontario

Sat 8/11

15:25-19:10

1 stop3h 45m

Las Vegas Harry Reid Intl

Mon 10/11

07:25-08:25

Nonstop1h 00m

$145

Flights are sorted by cheapest return flights first.

Deals found on 14/9

Showing 1-10 of 60 results
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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 return 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.

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 $817). Flying from Ontario in December will prove the most costly (average of $1,302). There are multiple factors that influence the price of a flight so comparing airlines, departure airports and times can help keep costs down.

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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 17 September 2025.
  • What are the most popular destinations to fly to from Ontario?

    For the current month, the most popular flights from Ontario are Denver, Dallas/Fort Worth Airport, Honolulu. Dallas/Fort Worth Airport, Denver, Guadalajara are the most popular locations from Ontario year round.

  • What is the cheapest flight from Ontario to anywhere?

    Users have flown out of Ontario for as low as $329 to San Salvador (prices may vary depending on the airline and departure time). On average, users have booked flights for $788 to fly from Ontario.

  • What is the cheapest first class flight from Ontario?

    If you’re looking to fly first-class from Ontario to anywhere, put Denver on your list as prices start at $1,847 for this destination.

  • What is the cheapest month to fly from Ontario?

    Currently, the cheapest month for flights from Ontario is January. The most expensive month for flights is December. The cheapest prices are shown above but prices will vary according to departure times, airlines, class and how early you book.

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

    View the cheapest flight destinations from Ontario:
    Fly from Ontario to Sydney from $1,509 round trip
    Fly from Ontario to Brisbane from $1,590 round trip
    Fly from Ontario to Melbourne from $1,792 round trip

  • How does Cheapflights help users find flights from Ontario?

    Cheapflights goes through 900+ travel sites to look for the best flight deals for flights from Ontario. Too many options? Cheapflights also provides filters for things like airlines, price ranges, and number of stops to help you make a decision easily.

  • Why should you use Cheapflights to find cheap flight tickets from Ontario?

    It’s simple! Cheapflights, which is free to use for everyone, saves millions of users time and money every year by helping them find the cheapest and most suitable flights from Ontario.

  • Can Cheapflights find flights from Ontario with no change fees?

    Certainly. Search results for flights from Ontario shown to you on Cheapflights can be narrowed down with different useful search filters, which includes flexible booking options.

  • Can Cheapflights notify me if prices for flights from Ontario become cheaper?

    Yes, Cheapflights has a feature called Price Alerts, which offers users the ability to be notified when flight prices change. Track prices for your flight from Ontario today and book when you’re ready!

See more FAQs

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from Ontario?

Cheapflights goes through 900+ travel sites to look for the best flight deals for flights from Ontario. Too many options? Cheapflights also provides filters for things like airlines, price ranges, and number of stops to help you make a decision easily.

Why should you use Cheapflights to find cheap flight tickets from Ontario?

It’s simple! Cheapflights, which is free to use for everyone, saves millions of users time and money every year by helping them find the cheapest and most suitable flights from Ontario.

Can Cheapflights find flights from Ontario with no change fees?

Certainly. Search results for flights from Ontario shown to you on Cheapflights can be narrowed down with different useful search filters, which includes flexible booking options.

Can Cheapflights notify me if prices for flights from Ontario become cheaper?

Yes, Cheapflights has a feature called Price Alerts, which offers users the ability to be notified when flight prices change. Track prices for your flight from Ontario today and book when you’re ready!

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