HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
San Sebastian

$581+ Cheap flights from Ontario (ONT) to San Sebastian (EAS)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 2/22. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — EAS
Feb 25 — Mar 41
Wed 2/25
Wed 3/4
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Ontario to San Sebastian 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 San Sebastian

Cheapest flights from Ontario to San Sebastian
Explore the most affordable flight options available from Ontario to San Sebastian. Find the lowest fares from popular airlines and budget airlines, with prices last updated on January 26, 2026.

This American Airlines deal was found by Cheapflights users on 1/25. 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.
Sun 2/227:00 am
ONT
-
EAS
2 stops16h 40m
American Airlines
Sat 3/79:30 pm
EAS
-
ONT
2 stops20h 36m
American Airlines
Deal found 1/25$581
This American Airlines deal was found by Cheapflights users on 1/26. 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 2/37:16 am
ONT
-
EAS
2 stops16h 24m
American Airlines
Wed 2/119:30 pm
EAS
-
ONT
2 stops21h 36m
American Airlines
Deal found 1/26$983
This KAYAK deal was found by Cheapflights users on 1/26. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 2/47:16 am
ONT
-
EAS
2 stops20h 44m
Multiple Airlines
Thu 2/121:40 pm
EAS
-
ONT
2 stops43h 19m
Multiple Airlines
Deal found 1/26$1,018
This Iberia deal was found by Cheapflights users on 1/25. 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.
Fri 9/1812:47 pm
ONT
-
EAS
2 stops23h 03m
Iberia
Mon 9/219:20 am
EAS
-
ONT
2 stops21h 30m
Iberia
Deal found 1/25$1,356
This KAYAK deal was found by Cheapflights users on 1/25. 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/1410:25 am
ONT
-
EAS
2 stops25h 25m
Iberia
Wed 6/249:30 pm
EAS
-
ONT
2 stops32h 56m
Iberia
Deal found 1/25$1,645
This Iberia deal was found by Cheapflights users on 1/25. 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 2/2510:56 am
ONT
-
EAS
2 stops17h 04m
Iberia
Sun 3/19:30 pm
EAS
-
ONT
2 stops34h 19m
Iberia
Deal found 1/25$1,738

Find flight deals from Ontario to San Sebastian

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to San Sebastian (EAS). 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 January 26, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$581
(American Airlines)

Popular in

February

Cheapest in

January

Average price

$567
Provider with most accurate pricing for Los Angeles-San Sebastián flight deals.
Search Deals
Provider most trusted by Cheapflights users for Los Angeles-San Sebastián flights.
Search Deals
From Ontario to San Sebastián
Search Deals
High demand for flights, 3% potential price rise
Search Deals
Cheapest flight prices on average. 5% potential price decrease ($63 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in January 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ontario to San Sebastian 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 January 26, 2026.
Use the filters below to find and compare flights from Ontario to San Sebastian that are best for you.

Fly from

Ontario

Fly to

San Sebastian

Route

Depart

Return

Price

OntarioSan Sebastian

ONT - EAS

ONTEAS

Ontario

Sun 2/22

7:00 am-8:40 am

2 stops16h 40m

San Sebastián

Sat 3/7

9:30 pm-9:06 am

2 stops20h 36m

$581

OntarioSan Sebastian

ONT - EAS

ONTEAS

Ontario

Thu 2/5

6:00 am-8:40 am

2 stops17h 40m

San Sebastián

Wed 2/11

9:30 pm-10:06 am

2 stops21h 36m

$983

OntarioSan Sebastian

ONT - EAS

ONTEAS

Ontario

Sun 6/14

10:25 am-8:50 pm

2 stops25h 25m

San Sebastián

Wed 6/24

9:30 pm-9:26 pm

2 stops32h 56m

$1,645

OntarioSan Sebastian

ONT - EAS

ONTEAS

Ontario

Wed 2/25

7:00 am-1:00 pm

2 stops21h 00m

San Sebastián

Sun 3/1

9:30 pm-10:49 pm

2 stops34h 19m

$1,738

OntarioSan Sebastian

ONT - EAS

ONTEAS

Ontario

Sun 7/5

7:20 am-4:40 pm

2 stops24h 20m

$910

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/26

Best time to book a flight from Ontario to San Sebastian

Have a flexible travel schedule? Discover the best time to fly to San Sebastian 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 San Sebastian

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

Currently, January is the cheapest month in which you can book a flight from Ontario to San Sebastian (average of $505). Flying from Ontario to San Sebastian in June is currently the most expensive (average of $1,005). 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.

Related info for your journey

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

  • How long is the flight from Ontario to San Sebastian?

    A quick flight from Ontario to San Sebastian can take about 16h 40m. American Airlines provides one of the quickest options available for as low as $581. Airlines will cover a distance of 5729 mi. This flight may include one or multiple stops.

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

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

  • How can I find direct flights from Ontario to San Sebastian?

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

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

    Yes. Cheapflights offers flight deals from Ontario to San Sebastian 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 San Sebastian?

    Currently, January is the cheapest month in which you can book a flight from Ontario to San Sebastian (average of $505). Flying from Ontario to San Sebastian in June is currently the most expensive (average of $1,005). 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.

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.