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Southeast Europe

$256+ Cheap flights from Ontario (ONT) to Southeast Europe

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 5/6. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — ATH
Jan 22 — Jan 291
Thu 1/22
Thu 1/29
1 adult, Economy
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Cheap flight deals from Ontario to Southeast Europe

Cheapest flights from Ontario to Southeast Europe
Explore the most affordable flight options available from Ontario to Southeast Europe. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 23, 2025.

This United Airlines deal was found by Cheapflights users on 12/20. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/236:39 pmONT - ATH
2 stops43h 46mUnited Airlines
Mon 1/191:10 pmATH - ONT
2 stops19h 43mUnited Airlines
Deal found 12/20$862
This United Airlines deal was found by Cheapflights users on 12/22. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/255:05 amONT - ATH
2 stops33h 25mUnited Airlines
Mon 1/51:10 pmATH - ONT
2 stops38h 41mUnited Airlines
Deal found 12/22$883
This oojo deal was found by Cheapflights users on 12/22. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/2412:45 pmONT - ATH
2 stops26h 20mBritish Airways
Wed 1/147:50 amATH - ONT
2 stops24h 58mBritish Airways
Deal found 12/22$929
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/315:05 amONT - ZAG
2 stops23h 45mUnited Airlines
Thu 1/86:10 amZAG - ONT
2 stops23h 48mUnited Airlines
Deal found 12/23$982
This United Airlines deal was found by Cheapflights users on 12/22. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/316:00 amONT - ZAG
2 stops22h 50mUnited Airlines
Wed 1/72:25 pmZAG - ONT
2 stops39h 33mUnited Airlines
Deal found 12/22$1,003
This Delta deal was found by Cheapflights users on 12/22. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/2511:15 amONT - OTP
2 stops19h 55mDelta
Thu 1/86:00 amOTP - ONT
2 stops25h 05mDelta
Deal found 12/22$1,049
This Delta deal was found by Cheapflights users on 12/22. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/2511:15 amONT - OTP
2 stops19h 55mDelta
Fri 1/96:00 amOTP - ONT
2 stops20h 12mDelta
Deal found 12/22$1,056
This United Airlines deal was found by Cheapflights users on 12/22. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/266:00 amONT - OTP
2 stops22h 10mUnited Airlines
Thu 1/85:50 amOTP - ONT
2 stops25h 08mUnited Airlines
Deal found 12/22$1,084
This United Airlines deal was found by Cheapflights users on 12/22. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/236:39 pmONT - OTP
2 stops43h 16mUnited Airlines
Tue 12/305:55 amOTP - ONT
2 stops26h 46mUnited Airlines
Deal found 12/22$1,088
This oojo deal was found by Cheapflights users on 12/21. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/2312:45 pmONT - ATH
2 stops26h 35mBritish Airways
Mon 12/294:55 pmATH - ONT
2 stops38h 03mBritish Airways
Deal found 12/21$1,263
This United Airlines deal was found by Cheapflights users on 12/22. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/236:39 pmONT - ATH
2 stops43h 46mUnited Airlines
Tue 12/306:35 amATH - ONT
2 stops21h 08mUnited Airlines
Deal found 12/22$1,324
This oojo deal was found by Cheapflights users on 12/20. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/2412:45 pmONT - ATH
2 stops20h 05mBritish Airways
Fri 12/267:50 pmATH - ONT
2 stops32h 27mBritish Airways
Deal found 12/20$1,356

Find flight deals from Ontario to Southeast Europe

Keep the following information in mind while searching for Ontario to Southeast Europe flight deals. Data was last updated December 23, 2025.

Most accurate provider

CheapOair
3 stars

Most trusted provider

CheapOair
3 stars

Round-trip from

$488
(United Airlines)

One-way from

$256
(oojo)

Popular in

December

Cheapest in

February

Average price

$1,110
Provider with most accurate pricing for Los Angeles-Athens Eleftherios V. flight deals.
Search Deals
Provider most trusted by Cheapflights users for Los Angeles-Athens Eleftherios V. flights.
Search Deals
From Ontario to Southeast Europe
Search Deals
One-way flight from Ontario to Southeast Europe
Search Deals
Highest demand for flights based on searches. 4% potential increase in price ($35 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($30 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ontario to Southeast Europe 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 23, 2025.
Use the filters below to find and compare flights from Ontario to Southeast Europe that are best for you.

Fly from

Ontario

Fly to

Southeast Europe

Route

Depart

Return

Price

OntarioCluj Napoca

ONT - CLJ

ONTCLJ

Ontario

Mon 1/19

5:05 am-1:40 pm

2 stops22h 35m

Cluj Napoca

Tue 2/3

2:25 pm-10:53 pm

2 stops18h 28m

$488

OntarioAthens

ONT - ATH

ONTATH

Ontario

Thu 2/5

5:05 am-12:00 pm

3 stops20h 55m

Athens Eleftherios V.

Thu 2/12

6:25 am-9:59 pm

2 stops25h 34m

$506

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

Wed 2/18

8:00 am-2:00 pm

2 stops20h 00m

Bucharest Otopeni Intl

Wed 3/4

6:05 am-10:57 pm

2 stops26h 52m

$514

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

Wed 3/25

5:15 am-2:00 pm

2 stops23h 45m

Bucharest Otopeni Intl

Wed 4/8

6:05 am-5:47 pm

2 stops21h 42m

$514

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

Sun 3/15

1:40 pm-11:50 pm

2 stops25h 10m

Bucharest Otopeni Intl

Wed 3/25

6:05 am-10:25 pm

2 stops25h 20m

$514

OntarioAthens

ONT - ATH

ONTATH

Ontario

Thu 1/29

6:00 am-4:15 pm

2 stops24h 15m

Athens Eleftherios V.

Mon 2/2

6:35 am-12:47 pm

2 stops40h 12m

$516

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

Mon 3/23

5:15 am-6:35 pm

2 stops28h 20m

Bucharest Otopeni Intl

Mon 4/6

1:50 pm-6:02 pm

2 stops38h 12m

$522

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

Wed 4/22

5:02 pm-12:25 am

2 stops21h 23m

Bucharest Otopeni Intl

Wed 5/6

8:25 am-9:56 pm

2 stops23h 31m

$523

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

Wed 3/25

2:47 pm-11:30 pm

2 stops23h 43m

Bucharest Otopeni Intl

Wed 4/8

8:25 am-11:40 pm

2 stops25h 15m

$523

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

Thu 2/5

6:00 am-8:10 pm

2 stops28h 10m

Bucharest Otopeni Intl

Thu 2/12

8:35 am-9:05 pm

2 stops22h 30m

$525

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/20

Showing 1-10 of 60 results
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Best time to book a flight from Ontario to Southeast Europe

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

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

Currently, August is the cheapest month in which you can book a flight from Ontario to Southeast Europe (average of $424). Flying from Ontario to Southeast Europe in June is currently the most expensive (average of $588). 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 YMH?

Find hourly flight availability from Ontario to Southeast Europe. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated December 23, 2025.

A simple way to save on the total cost of your ticket is to fly from Ontario to Southeast Europe in the afternoon. If you’re flexible enough to do this you can expect to save up to 8% on your trip compared to booking a flight in the evening.

Reviews of airlines servicing Southeast Europe

Get insights into the airlines that provide service to Southeast Europe. 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 Southeast Europe. Reviews last updated December 23, 2025.
Get a feel of what it's like to fly with United Airlines from Ontario to Southeast Europe by reading reviews from past customers. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
9,105 reviews

Comfort

7.3

Overall

7.4

Crew

8.1

Entertainment

7.1

Food

6.6

Boarding

7.7

Reviews

1 / 20
4.0
Okay

Thomas,Mar 2025

SFO - TPE

When I asked for an extra snack, I got an unhappy look from the stewardess. Geez, does one extra snack really affect the bottom line??
United Airlines
7.4
Good
9,105 reviews
United Airlines
7.4
Good
9,105 reviews

Comfort

7.3

Overall

7.4

Crew

8.1

Entertainment

7.1

Food

6.6

Boarding

7.7

Reviews

1 / 20
4.0
Okay

Thomas,Mar 2025

SFO - TPE

When I asked for an extra snack, I got an unhappy look from the stewardess. Geez, does one extra snack really affect the bottom line??

Related info for your journey

Find useful and relevant information for your journey from Ontario to Southeast Europe. 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 Southeast Europe?

    Ontario (ONT), located 3.1 mi from the city center, is the airport you fly out of when you book flights from Ontario to Southeast Europe.

  • How long is the flight from Ontario to Southeast Europe?

    Departing from Ontario to Southeast Europe will take you 21h 23m. The distance between Ontario and Southeast Europe is about 6541 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the most popular routes from Ontario to Southeast Europe?

    The most popular flight routes from Ontario to Southeast Europe are Ontario - Athens Eleftherios V., Ontario - Bucharest Otopeni Intl and Ontario - Belgrade Nikola Tesla.

  • Can I find deals for flights from Ontario to Southeast Europe that include hotel bookings?

    Yes. In addition to deals on Ontario to Southeast Europe flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Ontario to Southeast Europe?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Ontario to Southeast Europe.

  • Can I find deals for business class flights from Ontario to Southeast Europe?

    Yes. Cheapflights offers flight deals from Ontario to Southeast Europe 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 Southeast Europe?

    Currently, August is the cheapest month in which you can book a flight from Ontario to Southeast Europe (average of $424). Flying from Ontario to Southeast Europe in June is currently the most expensive (average of $588). 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.

See more FAQs

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Top airline flying from Ontario to Southeast Europe

Discover the top airline that operate flights from Ontario to Southeast Europe. 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 23, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$660Average$1,098FlexibilityNo cancel feeOn-time69%

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