HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Southeast Europe

$437+ 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 8/10. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — ATH
May 6 — May 131
Tue 5/6
Tue 5/13
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Ontario to Southeast Europe with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

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 May 1, 2025.

Most accurate provider

AranGrant
3 stars

Most trusted provider

AranGrant
3 stars

Round-trip from

$589
(Delta)

One-way from

$437
(United)

Popular in

June

Cheapest in

November

Average price

$963
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. 23% potential increase in price ($255 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($34 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in May 2025
Search Deals

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 May 1, 2025.

This Ovago deal was found by Cheapflights users on 4/29. 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 Ovago is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/2910:55 amONT - OTP
2 stops19h 55mBritish Airways
Wed 11/128:05 amOTP - ONT
2 stops23h 55mBritish Airways
Deal found 4/29$585
This Delta deal was found by Cheapflights users on 4/30. 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.
Mon 10/1311:29 amONT - OTP
2 stops19h 51mDelta
Fri 10/246:30 amOTP - ONT
2 stops26h 11mDelta
Deal found 4/30$589
This Iberia deal was found by Cheapflights users on 4/30. 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 Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/243:00 pmONT - ATH
2 stops23h 50mMultiple Airlines
Mon 10/208:45 pmATH - ONT
2 stops37h 17mMultiple Airlines
Deal found 4/30$638
This United Airlines deal was found by Cheapflights users on 4/30. 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.
Fri 12/510:40 amONT - ATH
2 stops19h 45mUnited Airlines
Fri 12/127:00 amATH - ONT
2 stops23h 17mUnited Airlines
Deal found 4/30$655
This United Airlines deal was found by Cheapflights users on 4/29. 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.
Mon 9/81:15 pmONT - OTP
2 stops17h 35mUnited Airlines
Sun 9/286:00 amOTP - ONT
2 stops21h 32mUnited Airlines
Deal found 4/29$671
This Ovago deal was found by Cheapflights users on 4/30. 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.
Tue 10/1410:55 amONT - ATH
2 stops19h 45mBritish Airways
Tue 10/218:00 pmATH - ONT
2 stops35h 40mBritish Airways
Deal found 4/30$676
This United Airlines deal was found by Cheapflights users on 4/29. 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.
Wed 10/297:00 amONT - BEG
2 stops21h 55mUnited Airlines
Wed 11/126:20 amBEG - ONT
2 stops22h 57mUnited Airlines
Deal found 4/29$682
This United deal was found by Cheapflights users on 4/30. 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 is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/277:00 amONT - BEG
2 stops19h 25mMultiple Airlines
Mon 11/101:40 pmBEG - ONT
2 stops41h 55mMultiple Airlines
Deal found 4/30$704
This Delta deal was found by Cheapflights users on 4/29. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/2010:59 pmONT - ATH
1 stop25h 56mDelta
Thu 10/26:30 amATH - ONT
2 stops20h 47mDelta
Deal found 4/29$732
This Air Canada deal was found by Cheapflights users on 4/29. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/215:10 amONT - ATH
2 stops18h 55mAir Canada
Wed 10/13:30 pmATH - ONT
2 stops31h 02mAir Canada
Deal found 4/29$738
This United Airlines deal was found by Cheapflights users on 4/30. 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.
Mon 9/86:04 amONT - DBV
2 stops19h 11mUnited Airlines
Mon 9/2212:15 pmDBV - ONT
2 stops41h 18mUnited Airlines
Deal found 4/30$742
This United deal was found by Cheapflights users on 4/30. 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 is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/206:00 amONT - OTP
2 stops31h 30mMultiple Airlines
Thu 5/291:55 pmOTP - ONT
2 stops18h 50mMultiple Airlines
Deal found 4/30$746

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 May 1, 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

Mon 10/13

11:29 am-5:20 pm

2 stops19h 51m

Bucharest Otopeni Intl

Fri 10/24

6:30 am-10:41 pm

2 stops26h 11m

$589

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

Mon 10/27

10:55 am-3:35 pm

2 stops19h 40m

Bucharest Otopeni Intl

Mon 11/10

8:05 am-9:41 pm

2 stops23h 36m

$652

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

Mon 9/8

1:15 pm-4:50 pm

2 stops17h 35m

Bucharest Otopeni Intl

Sun 9/28

6:00 am-5:32 pm

2 stops21h 32m

$671

OntarioBelgrade

ONT - BEG

ONTBEG

Ontario

Mon 10/27

7:00 am-10:25 am

2 stops19h 25m

Belgrade Nikola Tesla

Mon 11/10

1:40 pm-10:35 pm

2 stops41h 55m

$704

OntarioDubrovnik

ONT - DBV

ONTDBV

Ontario

Mon 9/8

6:04 am-10:15 am

2 stops19h 11m

Dubrovnik

Mon 9/22

12:15 pm-8:33 pm

2 stops41h 18m

$742

OntarioBucharest

ONT - OTP

ONTOTP

Ontario

Tue 5/20

6:00 am-11:30 pm

2 stops31h 30m

Bucharest Otopeni Intl

Thu 5/29

1:55 pm-10:45 pm

2 stops18h 50m

$746

OntarioSplit

ONT - SPU

ONTSPU

Ontario

Tue 9/9

9:55 am-10:55 pm

2 stops28h 00m

Split

Tue 9/30

6:30 am-11:46 pm

2 stops26h 16m

$753

OntarioDubrovnik

ONT - DBV

ONTDBV

Ontario

Tue 9/9

7:00 am-12:35 pm

2 stops20h 35m

Dubrovnik

Tue 9/30

1:25 pm-5:17 pm

2 stops36h 52m

$755

OntarioAthens

ONT - ATH

ONTATH

Ontario

Sun 7/13

12:46 pm-12:45 am

2 stops25h 59m

Athens Eleftherios V.

Tue 8/19

6:55 am-5:52 pm

2 stops20h 57m

$760

OntarioBelgrade

ONT - BEG

ONTBEG

Ontario

Wed 8/27

6:04 am-1:10 pm

2 stops22h 06m

Belgrade Nikola Tesla

Wed 9/10

6:10 am-5:37 pm

2 stops20h 27m

$767

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/30

Showing 1-10 of 60 results
1
2
3
...
6

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 $1,309). 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 May 1, 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 May 1, 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
7,934 reviews

Food

7.3

Overall

8.0

Entertainment

7.9

Crew

8.5

Comfort

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
7,934 reviews
Delta
8.0
Very good
7,934 reviews

Food

7.3

Overall

8.0

Entertainment

7.9

Crew

8.5

Comfort

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
1,334 reviews
Delta
8.0
Very good
7,934 reviews

Food

7.3

Overall

8.0

Entertainment

7.9

Crew

8.5

Comfort

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
1,446 reviews
Delta
8.0
Very good
7,934 reviews

Food

7.3

Overall

8.0

Entertainment

7.9

Crew

8.5

Comfort

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.
United Airlines
7.4
Good
8,696 reviews
Delta
8.0
Very good
7,934 reviews

Food

7.3

Overall

8.0

Entertainment

7.9

Crew

8.5

Comfort

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
7.4
Good
643 reviews
Delta
8.0
Very good
7,934 reviews

Food

7.3

Overall

8.0

Entertainment

7.9

Crew

8.5

Comfort

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 ($466), Delta ($499), and American Airlines ($509).

  • 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, 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 $1,309). 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

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Ontario to Southeast Europe

See prices for flight routes from nearby airports that may be better suited for you.
Los Angeles to Heathrow flights
San Francisco to Heathrow flights
San Francisco to Charles de Gaulle flights
Los Angeles to Charles de Gaulle flights
Los Angeles to Leonardo da Vinci/Fiumicino flights
San Francisco to Leonardo da Vinci/Fiumicino flights
Los Angeles to Barcelona-El Prat flights
Los Angeles to Madrid flights
San Francisco to Barcelona-El Prat flights
San Francisco to Frankfurt flights
Los Angeles to Gatwick flights
Los Angeles to London City flights
Los Angeles to Istanbul flights
San Francisco to Gatwick flights
San Francisco to Istanbul flights
San Francisco to London City flights
Los Angeles to Orly flights
Los Angeles to Athens flights
San Francisco to Orly flights
Los Angeles to Amsterdam flights
Los Angeles to Luton flights
Los Angeles to Frankfurt flights
Los Angeles to Dublin flights
San Francisco to Dublin flights
San Francisco to Lisbon flights
San Francisco to Amsterdam flights
San Diego to Heathrow flights
San Francisco to Malpensa flights
Los Angeles to Lisbon flights
San Francisco to Athens flights
Ontario to Charles de Gaulle flights
Los Angeles to Zurich flights
Ontario to Heathrow flights
San Francisco to Zurich flights
Los Angeles to Copenhagen flights
San Francisco to Linate flights
San Francisco to Madrid flights
Los Angeles to Malpensa flights
Los Angeles to Munich flights
San Francisco to Copenhagen flights
San Francisco to Munich flights
Ontario to Leonardo da Vinci/Fiumicino flights
Burbank to Charles de Gaulle flights
Santa Ana to Charles de Gaulle flights
Los Angeles to Vicenza flights
Los Angeles to Linate flights
Santa Ana to Leonardo da Vinci/Fiumicino flights
Las Vegas to Heathrow flights
Burbank to Leonardo da Vinci/Fiumicino flights
Los Angeles to Sabiha Gokcen flights

Top 4 airlines flying from Ontario to Southeast Europe

Discover the top 4 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 May 1, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$550Average$1,085FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$552Average$824FlexibilityNo cancel feeOn-time71%
DeltaCheapest$584Average$812FlexibilityNo cancel feeOn-timeN/A
KLMCheapest$602Average$1,516FlexibilityNo cancel feeOn-time75%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.