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$409+ Cheap flights from Ontario (ONT) to Porto (OPO)

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 10/7. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — OPO
Aug 25 — Sep 11
Mon 8/25
Mon 9/1
1 adult, Economy
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Cheap flight deals from Ontario to Porto

Discover tips and strategies to find the most affordable flight options for your journey from Ontario (ONT) to Porto (OPO). 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 20, 2025.

Round-trip from

$667
(United Airlines)

One-way from

$409
(United Airlines)

Popular in

December

Cheapest in

February

Average price

$996
From Ontario to Porto
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One-way flight from Ontario to Porto
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High demand for flights, 0% potential price rise
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Cheapest flight prices on average. 2% potential price decrease ($22 potential savings vs. average RT price).
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Average for round-trip flights in August 2025
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Find flight deals from Ontario to Porto

Cheapest flights from Ontario to Porto
Explore the most affordable flight options available from Ontario to Porto. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 20, 2025.

This United Airlines deal was found by Cheapflights users on 8/19. 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.
Mon 9/295:05 amONT - OPO
2 stops20h 30mUnited Airlines
Wed 10/156:00 amOPO - ONT
2 stops24h 30mUnited Airlines
Deal found 8/19$750
This American Airlines deal was found by Cheapflights users on 8/19. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/62:51 pmONT - OPO
2 stops17h 04mAmerican Airlines
Wed 10/2212:20 pmOPO - ONT
2 stops18h 22mAmerican Airlines
Deal found 8/19$759
This United Airlines deal was found by Cheapflights users on 8/19. 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 11/267:00 amONT - OPO
2 stops18h 30mUnited Airlines
Mon 12/112:30 pmOPO - ONT
2 stops18h 21mUnited Airlines
Deal found 8/19$872
This British Airways deal was found by Cheapflights users on 8/19. 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.
Mon 9/2912:45 pmONT - OPO
2 stops19h 10mBritish Airways
Wed 10/158:15 amOPO - ONT
2 stops22h 27mBritish Airways
Deal found 8/19$906
This United Airlines deal was found by Cheapflights users on 8/18. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/225:10 amONT - OPO
2 stops20h 25mUnited Airlines
Fri 10/36:00 amOPO - ONT
2 stops24h 52mUnited Airlines
Deal found 8/18$950
This United Airlines deal was found by Cheapflights users on 8/18. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/196:00 amONT - OPO
2 stops17h 45mUnited Airlines
Tue 8/2612:50 pmOPO - ONT
2 stops17h 40mUnited Airlines
Deal found 8/18$969
This United Airlines deal was found by Cheapflights users on 8/18. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/176:00 amONT - OPO
2 stops19h 20mUnited Airlines
Sun 9/2111:20 amOPO - ONT
2 stops43h 10mUnited Airlines
Deal found 8/18$990
This United Airlines deal was found by Cheapflights users on 8/19. 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.
Sun 9/217:00 amONT - OPO
2 stops15h 55mUnited Airlines
Tue 10/712:05 pmOPO - ONT
2 stops18h 47mUnited Airlines
Deal found 8/19$1,119
This United Airlines deal was found by Cheapflights users on 8/20. 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.
Sat 10/46:00 amONT - OPO
2 stops19h 45mUnited Airlines
Sat 10/1112:35 pmOPO - ONT
2 stops31h 38mUnited Airlines
Deal found 8/20$1,148
This United Airlines deal was found by Cheapflights users on 8/19. 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.
Thu 9/186:04 amONT - OPO
2 stops17h 01mUnited Airlines
Thu 9/2512:10 pmOPO - ONT
2 stops18h 20mUnited Airlines
Deal found 8/19$1,171
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.
Mon 12/2210:42 amONT - OPO
2 stops20h 13mUnited Airlines
Thu 1/86:00 amOPO - ONT
2 stops22h 17mUnited Airlines
Deal found 8/17$1,181
This United Airlines deal was found by Cheapflights users on 8/18. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/217:00 amONT - OPO
2 stops18h 30mUnited Airlines
Sat 11/296:00 amOPO - ONT
2 stops22h 33mUnited Airlines
Deal found 8/18$1,297

Cheapflights Fare Finder

 
Customize your flight search to find flights from Ontario to Porto 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 20, 2025.
Use the filters below to find and compare flights from Ontario to Porto that are best for you.

Fly from

Ontario

Fly to

Porto

Route

Depart

Return

Price

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Thu 1/15

7:00 am-11:40 am

2 stops20h 40m

Porto

Fri 1/23

12:30 pm-12:25 am

2 stops19h 55m

$667

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Mon 9/29

7:02 am-9:35 am

2 stops18h 33m

Porto

Wed 10/15

6:00 am-10:30 pm

2 stops24h 30m

$750

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Mon 10/6

2:51 pm-3:55 pm

2 stops17h 04m

Porto

Wed 10/22

12:20 pm-10:42 pm

2 stops18h 22m

$759

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Wed 11/26

7:00 am-9:30 am

2 stops18h 30m

Porto

Mon 12/1

12:30 pm-10:51 pm

2 stops18h 21m

$872

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Mon 9/29

12:45 pm-3:55 pm

2 stops19h 10m

Porto

Wed 10/15

8:15 am-10:42 pm

2 stops22h 27m

$906

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Mon 9/29

2:54 pm-3:55 pm

2 stops17h 01m

Porto

Wed 10/15

12:20 pm-10:42 pm

2 stops18h 22m

$906

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Mon 9/22

5:10 am-9:35 am

2 stops20h 25m

Porto

Fri 10/3

6:00 am-10:52 pm

2 stops24h 52m

$950

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Wed 9/17

6:00 am-9:20 am

2 stops19h 20m

Porto

Sun 9/21

11:20 am-10:30 pm

2 stops43h 10m

$990

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Sun 9/21

7:00 am-6:55 am

2 stops15h 55m

Porto

Tue 10/7

12:05 pm-10:52 pm

2 stops18h 47m

$1,119

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Sat 10/4

6:00 am-9:45 am

2 stops19h 45m

Porto

Sat 10/11

12:35 pm-12:13 pm

2 stops31h 38m

$1,148

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/20

Showing 1-10 of 20 results
1
2

Best time to book a flight from Ontario to Porto

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

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

Currently, January is the cheapest month in which you can book a flight from Ontario to Porto (average of $523). Flying from Ontario to Porto in June is currently the most expensive (average of $1,030). 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 OPO?

Find hourly flight availability from Ontario to Porto. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated August 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 Porto as you normally would.

Related info for your journey

Find useful and relevant information for your journey from Ontario to Porto. 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 Porto?

    United Airlines and American Airlines can get you from Ontario to Porto in just under 17h 04m. Your travel time can differ by up to 3h 36m. The distance from Ontario to Porto is about 5549 mi. This flight may include one or multiple stops.

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

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

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

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

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

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

    Currently, January is the cheapest month in which you can book a flight from Ontario to Porto (average of $523). Flying from Ontario to Porto in June is currently the most expensive (average of $1,030). 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

Traveling to a place near Porto?

Book flights to Porto if you plan to visit one of these locations
Aveiro
Arcos de Valdevez
Coimbra

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