ATH - ONT

$435 Find Cheap Flights from Athens to Ontario

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Athens to Ontario departing on 5/12. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Ontario

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Athens to Ontario, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Athens to Ontario, as well as popular online travel agencies
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Everything you should know

Cheapest round-trip
$953
United Airlines
Wed 4/15Thu 4/23
ATH - ONT • 2 stops
Cheapest one-way
$435
Multiple Airlines
Tue 5/12
ATH - ONT • 1 stop
Top airlines
United Airlines
Cheapest • from $953 (round-trip)
United Airlines
Best reviews • 7.4 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
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KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Ontario!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Athens to Ontario (ATH-ONT)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Athens to Ontario that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Athens to Ontario

Wed, Apr 15 - Thu, Apr 23
United Airlines Logo
6:55 am - 8:46 pm
ATH
-
ONT
23h 51m2 stops
United Airlines Logo
7:00 am - 10:35 am
ONT
-
ATH
17h 35m1 stop
$953United Airlines
Thu, Jan 22 - Mon, Jan 26
United Airlines Logo
6:25 am - 8:58 pm
ATH
-
ONT
24h 33m2 stops
United Airlines Logo
6:00 am - 4:35 pm
ONT
-
ATH
24h 35m2 stops
$958United Airlines
Wed, Apr 15 - Thu, Apr 23
KLM Logo
9:10 am - 6:15 pm
ATH
-
ONT
19h 05m1 stop
KLM Logo
7:00 am - 11:00 am
ONT
-
ATH
18h 00m1 stop
$963KLM
Fri, Apr 17 - Fri, Apr 24
Delta Logo
9:10 am - 6:15 pm
ATH
-
ONT
19h 05m1 stop
Delta Logo
7:00 am - 11:00 am
ONT
-
ATH
18h 00m1 stop
$986Delta
Wed, May 20 - Fri, May 29
United Airlines Logo
12:35 pm - 10:26 pm
ATH
-
ONT
19h 51m1 stop
United Airlines Logo
5:00 am - 10:10 am
ONT
-
ATH
19h 10m2 stops
$1,015United Airlines
Mon, Apr 13 - Thu, Apr 30
United Airlines Logo
6:55 am - 8:46 pm
ATH
-
ONT
23h 51m2 stops
United Airlines Logo
7:00 am - 10:35 am
ONT
-
ATH
17h 35m1 stop
$1,038United Airlines
Wed, Apr 15 - Sun, Apr 19
KLM Logo
9:10 am - 6:15 pm
ATH
-
ONT
19h 05m1 stop
KLM Logo
7:00 am - 11:00 am
ONT
-
ATH
18h 00m1 stop
$1,053KLM
Mon, Jan 26 - Mon, Feb 9
Iberia Logo
3:55 pm - 10:08 am
ATH
-
ONT
28h 13m2 stops
Iberia Logo
10:58 am - 3:15 pm
ONT
-
ATH
18h 17m2 stops
$1,056Iberia
Tue, May 5 - Mon, May 11
Air Serbia Logo
4:20 am - 10:09 pm
ATH
-
ONT
27h 49m2 stops
Air Serbia Logo
11:25 pm - 3:30 am
ONT
-
ATH
42h 05m2 stops
$1,183Air Serbia
Wed, May 6 - Sun, May 17
KLM Logo
9:10 am - 6:15 pm
ATH
-
ONT
19h 05m1 stop
KLM Logo
7:00 am - 11:00 am
ONT
-
ATH
18h 00m1 stop
$1,185KLM
Booking Insights

KAYAK's insights & trends for Athens to Ontario flights

Get data-powered insights and trends into flights from Athens to Ontario to help you find the cheapest flights, the best time to fly and much more.

Which airlines provide the cheapest flights from Athens to Ontario?

The cheapest round-trip price for the route for each airline clicked by KAYAK users in the last 72 hours.

In the past 3 days, the cheapest round-trip tickets from Athens to Ontario were found on United Airlines ($953) and KLM ($963).

Which airlines fly non-stop between Athens and Ontario?

Airline and price data is aggregated from results in KAYAK’s search results from the last 2 weeks for round-trip flights from Athens to Ontario.

There is just one airline that flies from Athens to Ontario direct and that is United Airlines. The best round-trip deal found from United Airlines for the route is $913.

Good to know

Cheapest flight$435
Flight from Athens to Ontario

When to book flights from Athens to Ontario

Are your dates flexible? Find out the best times to travel from Athens to Ontario based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Athens to Ontario

  • What is the cheapest flight from Athens to Ontario?

    In the last 3 days, the lowest price for a flight from Athens to Ontario was $435 for a one-way ticket and $953 for a round-trip.

  • Do I need a passport to fly between Athens and Ontario?

    A passport is required to fly from Athens to Ontario.

  • Which aircraft models fly most regularly from Athens to Ontario?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from Athens to Ontario?

    Star Alliance is the only airline alliance operating flights between Athens and Ontario.

  • How does KAYAK find such low prices on flights from Athens to Ontario?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Athens to Ontario.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Athens to Ontario?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Ontario from Athens is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Athens to Ontario?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Ontario with an airline and back to Athens with another airline. Booking your flights between Athens and ONT can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Athens to Ontario?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Ontario from Athens up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top airline flying from Athens to Ontario

 
See real verified KAYAK customer reviews for airlines flying from Athens to Ontario. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Athens to Ontario? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.4
United AirlinesOverall score based on 9092 reviews
8.1Crew
6.6Food
7.7Boarding
7.3Comfort
7.1Entertainment
Airline reviews

Movie selection is good. Crew did not understand mileage program and were no help. Sick later. Food?

6.0 GoodSue, Dec 2025
SJO - SFO
Read more United Airlines reviews

Movie selection is good. Crew did not understand mileage program and were no help. Sick later. Food?

We boarded late. The crew at the airport was dismissive. The seat cushion on the plane was uncomfortable.

United needs to step up their game. Delayed flight leaving Seattle, San Francisco. Older aircraft, not very comfortable.

The flight attendants were very rude, beyond comprehension. I took a business class from London to SFO for the first time on United. When I asked for a second piece of bread during dinner, the serving attendant threw a 3rd bread on my plate and said, “here. You can have this one too”! I couldn’t believe the rudeness of the attendant. Most all attendants were very rude, unhelpful, sing the food was absolutely disgusting. Never fly United internationally in business class. My flight back to SFO was a nightmare!!

Plane boarded early a quickly, was mostly full. We left close to on time. And landed early.

Very disappointed with food service. They ran out of entree selections- so for the last 10 rows only option was lentil stew. Not a fan. Then the morning service (pizza twist) was lukewarm at best- I exited my 12 hour flight having eaten a roll and dessert. They knew it was a full flight.

7 hours delayed due to operational issues on United’s end. Basically laziness.

Flight from Rome to SFO was excellent compared To our flight to Europe from SFO. The food was much tastier. You can see how UNITED is skimping, though. Instead of getting something mid flight you had to ask for it. It was not automatically served. There was a cookie at the end of the arrival meal, for example that tasted like it just came out of a box. They used to serve a little container of nuts, now … a tiny container of nuts, mixed with pretzels. This was business class that you really have to pay for! But this is minor complaints compared to the overall. My major complaint is the position of the even numbered seats by the windows. You have to turn around to see your window & the positioning as some other controls are harder to get at. This is compared to the odd number seat that are perfectly aligned.

The food quality sucks. One must starve if they do not eat flesh Or wheat based products Some variety would be expected. The trivial amount of snacks and or food is inhumane

Flight was timely, relatively comfortable, with decent entertainment and food served. Only problem encountered was with the free messaging which I highly appreciate, but it did not work from iphone to non-iphones.

Everything you need to know for your flight from Athens to Ontario

Information on your arrival and departure airports