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Southeast Europe

$432+ 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 3/31. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — ATH
Feb 25 — Mar 41
Tue 2/25
Tue 3/4
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 February 20, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$537
(Delta)

One-way from

$432
(United Airlines)

Popular in

June

Cheapest in

November

Average price

$630
Provider with most accurate pricing for Los Angeles-Athens Eleftherios V. flight deals.
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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. 28% potential increase in price ($341 potential increase over avg. RT price).
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Cheapest flight prices on average. 6% potential price decrease ($50 potential savings vs. average RT price).
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Average for round-trip flights in February 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 February 20, 2025.

This Delta deal was found by Cheapflights users on 2/19. 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.
Tue 3/185:30 pmONT - ATH
2 stops31h 05mDelta
Tue 4/110:30 amATH - ONT
2 stops23h 26mDelta
Deal found 2/19$537
This United Airlines deal was found by Cheapflights users on 2/19. 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 3/196:00 amONT - ATH
2 stops18h 10mUnited Airlines
Wed 3/2612:55 pmATH - ONT
2 stops32h 49mUnited Airlines
Deal found 2/19$608
This United Airlines deal was found by Cheapflights users on 2/19. 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 4/165:00 amONT - CLJ
2 stops26h 20mUnited Airlines
Thu 5/86:00 amCLJ - ONT
2 stops24h 53mUnited Airlines
Deal found 2/19$629
This KLM deal was found by Cheapflights users on 2/20. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/206:00 amONT - ATH
2 stops24h 35mKLM
Thu 2/276:00 amATH - ONT
2 stops26h 52mKLM
Deal found 2/20$673
This American Airlines deal was found by Cheapflights users on 2/18. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/38:48 amONT - ATH
2 stops20h 17mAmerican Airlines
Tue 12/97:45 amATH - ONT
3 stops23h 52mAmerican Airlines
Deal found 2/18$677
This KLM deal was found by Cheapflights users on 2/20. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 2/206:00 amONT - ATH
2 stops24h 35mMultiple Airlines
Wed 2/263:25 amATH - ONT
2 stops23h 03mMultiple Airlines
Deal found 2/20$684
This United Airlines deal was found by Cheapflights users on 2/20. 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.
Mon 4/144:23 pmONT - OTP
2 stops22h 37mUnited Airlines
Mon 4/286:05 amOTP - ONT
2 stops24h 37mUnited Airlines
Deal found 2/20$694
This British Airways deal was found by Cheapflights users on 2/19. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/235:02 pmONT - ATH
2 stops21h 53mBritish Airways
Sun 11/94:40 pmATH - ONT
2 stops35h 09mBritish Airways
Deal found 2/19$694
This United Airlines deal was found by Cheapflights users on 2/20. 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.
Thu 3/136:00 amONT - BEG
2 stops22h 55mUnited Airlines
Thu 4/31:55 pmBEG - ONT
2 stops18h 00mUnited Airlines
Deal found 2/20$710
This British Airways deal was found by Cheapflights users on 2/18. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/62:59 pmONT - OTP
2 stops23h 26mBritish Airways
Wed 8/138:25 amOTP - ONT
2 stops23h 10mBritish Airways
Deal found 2/18$728
This Delta deal was found by Cheapflights users on 2/19. 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.
Tue 3/2511:42 amONT - ZAG
2 stops18h 53mDelta
Fri 5/96:00 amZAG - ONT
2 stops20h 14mDelta
Deal found 2/19$849
This United deal was found by Cheapflights users on 2/19. 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 is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/217:05 amONT - CLJ
2 stops31h 25mMultiple Airlines
Wed 5/146:00 amCLJ - ONT
2 stops22h 01mMultiple Airlines
Deal found 2/19$864

Find flights from Ontario to Southeast Europe within your budget

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 February 20, 2025.

Fly from

Ontario

Fly to

Southeast Europe

Route

Depart

Return

Price

OntarioAthens

ONT - ATH

ONTATH

Ontario

Tue 3/18

5:30 pm-9:35 am

2 stops31h 05m

Athens Eleftherios V.

Tue 4/1

10:30 am-10:43 pm

1 stop22h 13m

$537

OntarioAthens

ONT - ATH

ONTATH

Ontario

Wed 3/19

6:00 am-9:10 am

2 stops18h 10m

Athens Eleftherios V.

Wed 3/26

12:55 pm-12:44 pm

2 stops32h 49m

$608

OntarioCluj Napoca

ONT - CLJ

ONTCLJ

Ontario

Wed 4/16

5:00 am-5:20 pm

2 stops26h 20m

Cluj Napoca

Thu 5/8

6:00 am-8:53 pm

2 stops24h 53m

$629

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

Mon 4/14

4:23 pm-1:00 am

2 stops22h 37m

Bucharest Otopeni Intl

Mon 4/28

6:05 am-8:42 pm

2 stops24h 37m

$694

OntarioAthens

ONT - ATH

ONTATH

Ontario

Thu 5/1

6:35 pm-6:00 am

2 stops25h 25m

Athens Eleftherios V.

Sun 5/11

7:45 pm-1:16 pm

2 stops27h 31m

$702

OntarioBelgrade

ONT - BEG

ONTBEG

Ontario

Thu 3/13

6:00 am-12:55 pm

2 stops22h 55m

Belgrade Nikola Tesla

Thu 4/3

1:55 pm-10:55 pm

2 stops18h 00m

$710

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

Wed 8/6

2:59 pm-12:25 am

2 stops23h 26m

Bucharest Otopeni Intl

Wed 8/13

8:25 am-9:35 pm

2 stops23h 10m

$728

OntarioAthens

ONT - ATH

ONTATH

Ontario

Wed 4/9

4:35 pm-12:50 am

2 stops22h 15m

Athens Eleftherios V.

Wed 4/16

8:45 am-9:58 pm

2 stops23h 13m

$731

OntarioZagreb

ONT - ZAG

ONTZAG

Ontario

Tue 3/25

11:42 am-2:35 pm

2 stops18h 53m

Zagreb Franjo Tuđman

Wed 5/7

6:00 am-5:14 pm

2 stops20h 14m

$849

OntarioCluj Napoca

ONT - CLJ

ONTCLJ

Ontario

Mon 4/21

7:05 am-12:30 am

2 stops31h 25m

Cluj Napoca

Wed 5/14

6:00 am-6:01 pm

2 stops22h 01m

$864

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/20

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.

Travel insights for flights from Ontario to Southeast Europe

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

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 $1,382). 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 February 20, 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 February 20, 2025.
To help decide which airline to fly from Ontario to Southeast Europe, see what other customers have to say about Delta, KLM and Virgin Atlantic. 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
8,220 reviews

Food

7.3

Overall

8.0

Comfort

8.0

Crew

8.5

Entertainment

7.9

Boarding

8.2

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
8,220 reviews
Delta
8.0
Very good
8,220 reviews

Food

7.3

Overall

8.0

Comfort

8.0

Crew

8.5

Entertainment

7.9

Boarding

8.2

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
1,333 reviews
Delta
8.0
Very good
8,220 reviews

Food

7.3

Overall

8.0

Comfort

8.0

Crew

8.5

Entertainment

7.9

Boarding

8.2

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.

Virgin Atlantic
7.5
Good
654 reviews
Delta
8.0
Very good
8,220 reviews

Food

7.3

Overall

8.0

Comfort

8.0

Crew

8.5

Entertainment

7.9

Boarding

8.2

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
7.4
Good
3,070 reviews
Delta
8.0
Very good
8,220 reviews

Food

7.3

Overall

8.0

Comfort

8.0

Crew

8.5

Entertainment

7.9

Boarding

8.2

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
7.4
Good
1,449 reviews
Delta
8.0
Very good
8,220 reviews

Food

7.3

Overall

8.0

Comfort

8.0

Crew

8.5

Entertainment

7.9

Boarding

8.2

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 ($432), British Airways ($452), and Iberia ($461).

  • 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 $1,382). 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 5 airlines flying from Ontario to Southeast Europe

Discover the top 5 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 February 20, 2025.
AirlineCheapestAverageFlexibilityOn-time
British AirwaysCheapest$537Average$909FlexibilityNo cancel feeOn-time70%
United AirlinesCheapest$550Average$1,048FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$552Average$825FlexibilityNo cancel feeOn-time71%
DeltaCheapest$571Average$812FlexibilityNo cancel feeOn-timeN/A
KLMCheapest$602Average$1,094FlexibilityNo cancel feeOn-time75%
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