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Southeast Europe

$399+ 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 10/20. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — ATH
jun. 23 — jun. 301
lun. 6/23
lun. 6/30
1 adult, Economy
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Cheap 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 junio 18, 2025.

Round-trip from

$520
(United Airlines)

One-way from

$399
(United Airlines)

Popular in

June

Cheapest in

November

Average price

$1,067
From Ontario to Southeast Europe
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One-way flight from Ontario to Southeast Europe
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Highest demand for flights based on searches. 18% potential increase in price ($188 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($24 potential savings vs. average RT price).
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Average for round-trip flights in June 2025
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Find 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 junio 18, 2025.

This United Airlines deal was found by Cheapflights users on 6/16. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 11/261:00 pmONT - OTP
2 stops26h 05mUnited Airlines
mié. 12/105:55 amOTP - ONT
3 stops26h 50mUnited Airlines
Deal found 6/16$520
This United Airlines deal was found by Cheapflights users on 6/16. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 12/21:40 pmONT - ATH
2 stops37h 15mUnited Airlines
mar. 12/166:25 amATH - ONT
2 stops21h 21mUnited Airlines
Deal found 6/16$524
This Delta deal was found by Cheapflights users on 6/16. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 12/510:59 pmONT - ATH
2 stops49h 36mDelta
lun. 12/153:35 amATH - ONT
2 stops29h 06mDelta
Deal found 6/16$537
This Finnair deal was found by Cheapflights users on 6/16. 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 Finnair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 11/111:59 pmONT - ATH
2 stops25h 51mMultiple Airlines
sáb. 11/151:00 pmATH - ONT
2 stops20h 45mMultiple Airlines
Deal found 6/16$540
This United Airlines deal was found by Cheapflights users on 6/17. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 8/127:00 amONT - CLJ
2 stops20h 05mUnited Airlines
jue. 8/286:00 amCLJ - ONT
2 stops21h 29mUnited Airlines
Deal found 6/17$555
This Iberia deal was found by Cheapflights users on 6/17. 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 Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 8/198:14 amONT - ATH
2 stops20h 56mIberia
vie. 8/2912:20 pmATH - ONT
2 stops21h 47mIberia
Deal found 6/17$583
This Delta deal was found by Cheapflights users on 6/16. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 11/266:43 amONT - OTP
2 stops43h 57mDelta
sáb. 12/131:55 pmOTP - ONT
2 stops43h 51mDelta
Deal found 6/16$601
This KLM deal was found by Cheapflights users on 6/17. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 8/217:05 amONT - ATH
1 stop17h 05mKLM
jue. 8/289:10 amATH - ONT
1 stop20h 01mKLM
Deal found 6/17$616
This United Airlines deal was found by Cheapflights users on 6/18. 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.
mar. 11/187:00 amONT - BEG
2 stops21h 05mUnited Airlines
mar. 12/26:05 amBEG - ONT
2 stops20h 41mUnited Airlines
Deal found 6/18$645
This United Airlines deal was found by Cheapflights users on 6/17. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 10/151:15 pmONT - ZAG
2 stops16h 00mUnited Airlines
mié. 10/296:15 amZAG - ONT
2 stops19h 19mUnited Airlines
Deal found 6/17$715
This Booking.com deal was found by Cheapflights users on 6/17. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 12/175:09 pmONT - OTP
2 stops17h 01mBritish Airways
mié. 12/318:05 amOTP - ONT
2 stops23h 37mBritish Airways
Deal found 6/17$723
This Orbitz deal was found by Cheapflights users on 6/16. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 12/512:53 pmONT - ATH
2 stops23h 02mBritish Airways
vie. 12/197:35 pmATH - ONT
2 stops32h 13mBritish Airways
Deal found 6/16$743

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 junio 18, 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

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

mié. 11/26

1:00 pm-1:05 am

2 stops26h 05m

Bucharest Otopeni Intl

mié. 12/10

5:55 am-10:45 pm

3 stops26h 50m

$520

OntarioAthens

ONT - ATH

ONTATH

Ontario

mar. 12/2

1:40 pm-12:55 pm

2 stops37h 15m

Athens Eleftherios V.

mar. 12/16

6:25 am-5:46 pm

2 stops21h 21m

$524

OntarioAthens

ONT - ATH

ONTATH

Ontario

vie. 12/5

10:59 pm-10:35 am

2 stops49h 36m

Athens Eleftherios V.

lun. 12/15

3:35 am-10:41 pm

2 stops29h 06m

$537

OntarioAthens

ONT - ATH

ONTATH

Ontario

sáb. 11/1

11:59 pm-10:50 am

2 stops25h 51m

Athens Eleftherios V.

sáb. 11/15

1:00 pm-11:45 pm

2 stops20h 45m

$540

OntarioCluj Napoca

ONT - CLJ

ONTCLJ

Ontario

mar. 8/12

7:00 am-1:05 pm

2 stops20h 05m

Cluj Napoca

jue. 8/28

6:00 am-5:29 pm

2 stops21h 29m

$555

OntarioAthens

ONT - ATH

ONTATH

Ontario

mar. 8/19

8:14 am-3:10 pm

2 stops20h 56m

Athens Eleftherios V.

vie. 8/29

12:20 pm-12:07 am

2 stops21h 47m

$583

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

mié. 11/26

6:43 am-12:40 pm

2 stops43h 57m

Bucharest Otopeni Intl

sáb. 12/13

1:55 pm-11:46 pm

2 stops43h 51m

$601

OntarioAthens

ONT - ATH

ONTATH

Ontario

jue. 8/21

7:05 am-10:10 am

1 stop17h 05m

Athens Eleftherios V.

jue. 8/28

9:10 am-7:11 pm

1 stop20h 01m

$616

OntarioBelgrade

ONT - BEG

ONTBEG

Ontario

mar. 11/18

7:00 am-1:05 pm

2 stops21h 05m

Belgrade Nikola Tesla

mar. 12/2

6:05 am-5:46 pm

2 stops20h 41m

$645

OntarioZagreb

ONT - ZAG

ONTZAG

Ontario

mié. 10/15

1:15 pm-2:15 pm

2 stops16h 00m

Zagreb Franjo Tuđman

mié. 10/29

6:15 am-5:34 pm

2 stops19h 19m

$715

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/17

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, November is the cheapest month in which you can book a flight from Ontario to Southeast Europe (average of $679). Flying from Ontario to Southeast Europe in June is currently the most expensive (average of $1,289). 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 junio 18, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Ontario to Southeast Europe as you normally would.

Rainfall in Southeast Europe by month

Plan your trip to Southeast Europe by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Southeast Europe ranges from 0.2 - 2.5 inches per month. December is typically the wettest month, when rainfall can reach 2.5 in. June is typically the driest time to visit Southeast Europe when rainfall is around 0.2 in.

Temperature in Southeast Europe by month

Plan your trip to Southeast Europe by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Southeast Europe, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 82.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 50.0 F).

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 junio 18, 2025.
To help decide which airline to fly from Ontario to Southeast Europe, see what other customers have to say about Delta, KLM and Air France. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,965 reviews

Overall

8.0

Comfort

7.9

Entertainment

7.9

Boarding

8.2

Crew

8.5

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Delta
8.0
Very good
7,965 reviews
Delta
8.0
Very good
7,965 reviews

Overall

8.0

Comfort

7.9

Entertainment

7.9

Boarding

8.2

Crew

8.5

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
KLM
7.8
Good
1,363 reviews
Delta
8.0
Very good
7,965 reviews

Overall

8.0

Comfort

7.9

Entertainment

7.9

Boarding

8.2

Crew

8.5

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Air France
7.5
Good
1,467 reviews
Delta
8.0
Very good
7,965 reviews

Overall

8.0

Comfort

7.9

Entertainment

7.9

Boarding

8.2

Crew

8.5

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
United Airlines
7.4
Good
8,809 reviews
Delta
8.0
Very good
7,965 reviews

Overall

8.0

Comfort

7.9

Entertainment

7.9

Boarding

8.2

Crew

8.5

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
JetBlue
7.3
Good
2,923 reviews
Delta
8.0
Very good
7,965 reviews

Overall

8.0

Comfort

7.9

Entertainment

7.9

Boarding

8.2

Crew

8.5

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

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.

  • What are the cheapest airlines to fly from Ontario to Southeast Europe one-way?

    The cheapest airlines for a one-way flight from Ontario to Southeast Europe are United Airlines ($399), Air France ($410), and KLM ($418).

  • 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 - Belgrade Nikola Tesla and Ontario - Bucharest Otopeni Intl.

  • 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, November is the cheapest month in which you can book a flight from Ontario to Southeast Europe (average of $679). Flying from Ontario to Southeast Europe in June is currently the most expensive (average of $1,289). 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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Alternative routes for Ontario to Southeast Europe

See prices for flight routes from nearby airports that may be better suited for you.
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Top 3 airlines flying from Ontario to Southeast Europe

Discover the top 3 airlines 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 junio 18, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$550Average$955FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$552Average$824FlexibilityNo cancel feeOn-time71%
DeltaCheapest$596Average$860FlexibilityNo cancel feeOn-timeN/A

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