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Southeast Europe

$395+ 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 11/2. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — ATH
ago. 5 — ago. 121
mar. 8/5
mar. 8/12
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 julio 31, 2025.

Round-trip from

$502
(United Airlines)

One-way from

$395
(Booking.com)

Popular in

June

Cheapest in

February

Average price

$901
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. 19% potential increase in price ($185 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($28 potential savings vs. average RT price).
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Average for round-trip flights in July 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 julio 31, 2025.

This United Airlines deal was found by Cheapflights users on 7/31. 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.
dom. 8/317:00 amONT - ATH
1 stop17h 30mUnited Airlines
mar. 10/71:10 pmATH - ONT
2 stops33h 41mUnited Airlines
Deal found 7/31$502
This United Airlines deal was found by Cheapflights users on 7/31. 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. 12/3110:42 amONT - OTP
2 stops27h 13mUnited Airlines
mar. 1/135:55 amOTP - ONT
2 stops25h 26mUnited Airlines
Deal found 7/31$525
This Delta deal was found by Cheapflights users on 7/31. 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.
dom. 8/177:05 amONT - ATH
1 stop16h 55mDelta
jue. 8/289:10 amATH - ONT
1 stop20h 01mDelta
Deal found 7/31$526
This Tripair deal was found by Cheapflights users on 7/30. 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 Tripair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 8/236:50 pmONT - ATH
2 stops30h 20mAir Canada
vie. 9/512:10 pmATH - ONT
2 stops34h 03mAir Canada
Deal found 7/30$595
This United Airlines deal was found by Cheapflights users on 7/30. 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. 10/286:05 amONT - BEG
2 stops23h 00mUnited Airlines
mar. 11/116:05 amBEG - ONT
2 stops20h 29mUnited Airlines
Deal found 7/30$620
This Ovago deal was found by Cheapflights users on 7/31. 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 Ovago is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 12/56:32 amONT - ATH
2 stops23h 23mBritish Airways
vie. 12/197:45 amATH - ONT
2 stops24h 18mBritish Airways
Deal found 7/31$629
This Iberia deal was found by Cheapflights users on 7/31. 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.
mié. 10/2910:57 amONT - OTP
2 stops19h 48mMultiple Airlines
mié. 11/128:05 amOTP - ONT
2 stops24h 24mMultiple Airlines
Deal found 7/31$642
This Ovago deal was found by Cheapflights users on 7/30. 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 Ovago is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 8/2612:22 pmONT - OTP
2 stops27h 03mBritish Airways
lun. 10/203:30 pmOTP - ONT
2 stops37h 05mBritish Airways
Deal found 7/30$643
This United Airlines deal was found by Cheapflights users on 7/30. 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.
dom. 8/177:00 amONT - CLJ
2 stops24h 15mUnited Airlines
jue. 9/46:00 amCLJ - ONT
2 stops21h 29mUnited Airlines
Deal found 7/30$656
This Delta deal was found by Cheapflights users on 7/30. 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.
dom. 8/177:05 amONT - OTP
2 stops19h 05mDelta
vie. 9/56:30 amOTP - ONT
2 stops26h 10mDelta
Deal found 7/30$665
This United Airlines deal was found by Cheapflights users on 7/29. 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. 11/121:33 pmONT - ZAG
2 stops15h 22mUnited Airlines
dom. 11/166:25 amZAG - ONT
2 stops24h 12mUnited Airlines
Deal found 7/29$668
This ResecentrumGruppen deal was found by Cheapflights users on 7/30. 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 ResecentrumGruppen is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 8/167:05 amONT - ATH
1 stop17h 05mKLM
vie. 8/299:10 amATH - ONT
1 stop20h 01mKLM
Deal found 7/30$669

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 julio 31, 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

OntarioAthens

ONT - ATH

ONTATH

Ontario

dom. 8/31

7:00 am-10:30 am

1 stop17h 30m

Athens Eleftherios V.

mar. 10/7

1:10 pm-12:51 pm

2 stops33h 41m

$502

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

mar. 1/27

5:03 pm-10:55 pm

2 stops19h 52m

Bucharest Otopeni Intl

mar. 2/10

8:00 am-10:02 pm

2 stops24h 02m

$512

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

mié. 12/31

10:42 am-11:55 pm

2 stops27h 13m

Bucharest Otopeni Intl

mar. 1/13

5:55 am-9:21 pm

2 stops25h 26m

$525

OntarioAthens

ONT - ATH

ONTATH

Ontario

dom. 8/17

7:05 am-10:00 am

1 stop16h 55m

Athens Eleftherios V.

jue. 8/28

9:10 am-7:11 pm

1 stop20h 01m

$526

OntarioAthens

ONT - ATH

ONTATH

Ontario

sáb. 8/23

6:50 pm-11:10 am

2 stops30h 20m

Athens Eleftherios V.

vie. 9/5

12:10 pm-12:13 pm

2 stops34h 03m

$595

OntarioBelgrade

ONT - BEG

ONTBEG

Ontario

mar. 10/28

6:05 am-1:05 pm

2 stops23h 00m

Belgrade Nikola Tesla

mar. 11/11

6:05 am-5:34 pm

2 stops20h 29m

$620

OntarioAthens

ONT - ATH

ONTATH

Ontario

vie. 12/5

6:32 am-3:55 pm

2 stops23h 23m

Athens Eleftherios V.

vie. 12/19

7:45 am-10:03 pm

2 stops24h 18m

$629

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

mié. 10/29

10:57 am-3:45 pm

2 stops19h 48m

Bucharest Otopeni Intl

mié. 11/12

8:05 am-10:29 pm

2 stops24h 24m

$642

OntarioCluj Napoca

ONT - CLJ

ONTCLJ

Ontario

dom. 8/17

7:00 am-5:15 pm

2 stops24h 15m

Cluj Napoca

jue. 9/4

6:00 am-5:29 pm

2 stops21h 29m

$656

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

dom. 8/17

7:05 am-12:10 pm

2 stops19h 05m

Bucharest Otopeni Intl

vie. 9/5

6:30 am-10:40 pm

2 stops26h 10m

$665

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/31

Showing 1-10 of 50 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 $1,287). 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 julio 31, 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.

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 julio 31, 2025.
Get a feel of what it's like to fly with Delta, KLM, and LOT 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.
Delta
8.0
Very good
7,981 reviews

Entertainment

7.9

Comfort

7.9

Boarding

8.2

Food

7.3

Overall

8.0

Crew

8.5

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
7,981 reviews
Delta
8.0
Very good
7,981 reviews

Entertainment

7.9

Comfort

7.9

Boarding

8.2

Food

7.3

Overall

8.0

Crew

8.5

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
1,383 reviews
Delta
8.0
Very good
7,981 reviews

Entertainment

7.9

Comfort

7.9

Boarding

8.2

Food

7.3

Overall

8.0

Crew

8.5

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.
LOT
7.6
Good
1,105 reviews
Delta
8.0
Very good
7,981 reviews

Entertainment

7.9

Comfort

7.9

Boarding

8.2

Food

7.3

Overall

8.0

Crew

8.5

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
8,900 reviews
Delta
8.0
Very good
7,981 reviews

Entertainment

7.9

Comfort

7.9

Boarding

8.2

Food

7.3

Overall

8.0

Crew

8.5

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.
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,981 reviews

Entertainment

7.9

Comfort

7.9

Boarding

8.2

Food

7.3

Overall

8.0

Crew

8.5

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 Air Canada ($395), United Airlines ($399), 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 - Bucharest Otopeni Intl and Ontario - Zagreb Franjo Tuđman.

  • 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 $1,287). 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 2 airlines flying from Ontario to Southeast Europe

Discover the top 2 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 julio 31, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$550Average$955FlexibilityNo cancel feeOn-time69%
DeltaCheapest$571Average$771FlexibilityNo cancel feeOn-timeN/A

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