HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Ontario

$718+ Cheap flights from Athens (ATH) to Ontario (ONT)

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 9/9. Fares are subject to change and may not be available on all flights or dates of travel.
ATH — ONT
Aug 22 — Aug 291
Fri 8/22
Fri 8/29
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Athens to Ontario 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 Athens to Ontario

Discover tips and strategies to find the most affordable flight options for your journey from Athens (ATH) to Ontario (ONT). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated August 17, 2025.

Round-trip from

$860
(United Airlines)

One-way from

$718
(Air Serbia)

Popular in

October

Cheapest in

June

Average price

$837
From Athens Eleftherios V. to Ontario
Search Deals
One-way flight from Athens Eleftherios V. to Ontario
Search Deals
Highest demand for flights based on searches. 2% potential increase in price ($19 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease ($17 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in August 2025
Search Deals

Find flight deals from Athens to Ontario

Cheapest flights from Athens to Ontario
Explore the most affordable flight options available from Athens to Ontario. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 17, 2025.

This United Airlines deal was found by Cheapflights users on 8/16. 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.
Tue 9/1610:25 amATH - ONT
2 stops22h 05mUnited Airlines
Mon 9/227:00 amONT - ATH
1 stop17h 30mUnited Airlines
Deal found 8/16$860
This United Airlines deal was found by Cheapflights users on 8/17. 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.
Wed 9/1012:35 pmATH - ONT
1 stop19h 55mUnited Airlines
Wed 9/246:04 amONT - ATH
2 stops21h 56mUnited Airlines
Deal found 8/17$862
This American Airlines deal was found by Cheapflights users on 8/17. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/27:55 amATH - ONT
2 stops20h 29mAmerican Airlines
Sat 9/62:54 pmONT - ATH
2 stops32h 21mAmerican Airlines
Deal found 8/17$872
This United Airlines deal was found by Cheapflights users on 8/16. 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.
Wed 10/297:05 amATH - ONT
2 stops24h 46mUnited Airlines
Wed 11/126:00 amONT - ATH
2 stops19h 35mUnited Airlines
Deal found 8/16$894
This United Airlines deal was found by Cheapflights users on 8/16. 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.
Thu 12/252:10 pmATH - ONT
2 stops37h 33mUnited Airlines
Mon 1/511:59 pmONT - ATH
2 stops30h 36mUnited Airlines
Deal found 8/16$910
This United Airlines deal was found by Cheapflights users on 8/16. 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.
Thu 12/252:10 pmATH - ONT
2 stops37h 33mUnited Airlines
Sun 1/45:05 amONT - ATH
2 stops44h 55mUnited Airlines
Deal found 8/16$927
This United Airlines deal was found by Cheapflights users on 8/16. 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.
Wed 12/242:20 pmATH - ONT
2 stops40h 47mUnited Airlines
Mon 1/51:40 pmONT - ATH
2 stops40h 55mUnited Airlines
Deal found 8/16$929
This United Airlines deal was found by Cheapflights users on 8/16. 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.
Wed 12/242:20 pmATH - ONT
2 stops40h 47mUnited Airlines
Sun 1/45:05 amONT - ATH
2 stops44h 55mUnited Airlines
Deal found 8/16$946
This Delta deal was found by Cheapflights users on 8/17. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/21:40 pmATH - ONT
2 stops36h 28mDelta
Sat 9/611:45 amONT - ATH
1 stop36h 15mDelta
Deal found 8/17$954
This Iberia deal was found by Cheapflights users on 8/16. 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 Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/158:25 pmATH - ONT
2 stops32h 29mMultiple Airlines
Mon 9/2210:53 amONT - ATH
2 stops19h 37mMultiple Airlines
Deal found 8/16$965
This United Airlines deal was found by Cheapflights users on 8/16. 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.
Tue 12/232:10 pmATH - ONT
2 stops40h 57mUnited Airlines
Mon 1/56:39 pmONT - ATH
2 stops35h 56mUnited Airlines
Deal found 8/16$970

Cheapflights Fare Finder

 
Customize your flight search to find flights from Athens to Ontario 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 August 17, 2025.
Use the filters below to find and compare flights from Athens to Ontario that are best for you.

Fly from

Athens

Fly to

Ontario

Route

Depart

Return

Price

AthensOntario

ATH - ONT

ATHONT

Athens Eleftherios V.

Wed 9/10

12:35 pm-10:30 pm

1 stop19h 55m

Ontario

Wed 9/24

6:04 am-2:00 pm

2 stops21h 56m

$860

AthensOntario

ATH - ONT

ATHONT

Athens Eleftherios V.

Fri 9/12

5:25 am-6:54 pm

2 stops23h 29m

Ontario

Fri 9/26

2:54 pm-2:00 am

2 stops25h 06m

$860

AthensOntario

ATH - ONT

ATHONT

Athens Eleftherios V.

Tue 9/16

12:35 pm-10:30 pm

1 stop19h 55m

Ontario

Mon 9/22

7:00 am-10:30 am

1 stop17h 30m

$860

AthensOntario

ATH - ONT

ATHONT

Athens Eleftherios V.

Tue 9/16

12:35 pm-10:30 pm

1 stop19h 55m

Ontario

Tue 9/23

7:00 am-10:30 am

1 stop17h 30m

$860

AthensOntario

ATH - ONT

ATHONT

Athens Eleftherios V.

Thu 9/18

12:35 pm-10:30 pm

1 stop19h 55m

Ontario

Thu 10/16

5:05 am-10:05 am

2 stops19h 00m

$860

AthensOntario

ATH - ONT

ATHONT

Athens Eleftherios V.

Tue 9/2

7:55 am-6:24 pm

2 stops20h 29m

Ontario

Sat 9/6

2:54 pm-9:15 am

2 stops32h 21m

$872

AthensOntario

ATH - ONT

ATHONT

Athens Eleftherios V.

Wed 10/29

7:05 am-10:51 pm

2 stops24h 46m

Ontario

Wed 11/12

6:00 am-11:35 am

2 stops19h 35m

$894

AthensOntario

ATH - ONT

ATHONT

Athens Eleftherios V.

Tue 9/9

4:25 pm-9:29 pm

2 stops39h 04m

$718

AthensOntario

ATH - ONT

ATHONT

Athens Eleftherios V.

Mon 9/8

4:20 pm-9:29 pm

2 stops39h 09m

$719

AthensOntario

ATH - ONT

ATHONT

Athens Eleftherios V.

Wed 9/3

4:20 am-9:29 pm

2 stops27h 09m

$757

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/15

Showing 1-10 of 18 results
1
2

Best time to book a flight from Athens to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from Athens 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 Athens to Ontario

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

Currently, August is the cheapest month in which you can book a flight from Athens to Ontario (average of $246). Flying from Athens to Ontario in March is currently the most expensive (average of $328). 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.

Reviews of airlines servicing Ontario

Get insights into the airlines that provide service to Ontario. 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 Ontario. Reviews last updated August 17, 2025.
Read through reviews of airlines operating flights from Athens to Ontario, such as United Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
8,919 reviews

Entertainment

7.1

Overall

7.4

Comfort

7.3

Crew

8.1

Boarding

7.7

Food

6.6

Reviews

1 / 20
4.0
Okay

Thomas,Apr 2025

TPE - SFO

The boarding experience was okay. The dietary food choices were limited, the midway snacks were hard and dry. The seat was uncomfortable - stiff seat cushion, seat back kept springing back to the upright position, narrow seat width. Love the app and the ability to track my luggage. Flight crew was efficient.
United Airlines
7.4
Good
8,919 reviews
United Airlines
7.4
Good
8,919 reviews

Entertainment

7.1

Overall

7.4

Comfort

7.3

Crew

8.1

Boarding

7.7

Food

6.6

Reviews

1 / 20
4.0
Okay

Thomas,Apr 2025

TPE - SFO

The boarding experience was okay. The dietary food choices were limited, the midway snacks were hard and dry. The seat was uncomfortable - stiff seat cushion, seat back kept springing back to the upright position, narrow seat width. Love the app and the ability to track my luggage. Flight crew was efficient.

Related info for your journey

Find useful and relevant information for your journey from Athens to Ontario. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

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

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

  • How can I find direct flights from Athens to Ontario?

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

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

    Yes. Cheapflights offers flight deals from Athens to Ontario 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 Athens to Ontario?

    Currently, August is the cheapest month in which you can book a flight from Athens to Ontario (average of $246). Flying from Athens to Ontario in March is currently the most expensive (average of $328). 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.

Top airline flying from Athens to Ontario

Discover the top airline that operate flights from Athens to Ontario. 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 August 17, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$913Average$1,037FlexibilityNo cancel feeOn-time69%

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.