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$451+ 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 1/5. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — OPO
Dec 4 — Dec 111
Thu 12/4
Thu 12/11
1 adult, Economy
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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 November 4, 2025.

This United Airlines deal was found by Cheapflights users on 11/3. 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 12/36:00 amONT - OPO
2 stops25h 25mUnited Airlines
Wed 12/106:00 amOPO - ONT
3 stops24h 49mUnited Airlines
Deal found 11/3$503
This Iberia deal was found by Cheapflights users on 11/2. 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.
Tue 11/46:10 amONT - OPO
2 stops17h 30mIberia
Tue 2/38:20 amOPO - ONT
2 stops22h 28mIberia
Deal found 11/2$958
This United Airlines deal was found by Cheapflights users on 11/2. 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 12/2611:59 pmONT - OPO
2 stops31h 06mUnited Airlines
Thu 1/86:00 amOPO - ONT
2 stops22h 58mUnited Airlines
Deal found 11/2$1,218
This United Airlines deal was found by Cheapflights users on 11/3. 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 12/17:00 amONT - OPO
2 stops20h 40mUnited Airlines
Fri 12/196:00 amOPO - ONT
2 stops24h 25mUnited Airlines
Deal found 11/3$1,228
This United Airlines deal was found by Cheapflights users on 11/2. 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 12/241:40 pmONT - OPO
2 stops17h 45mUnited Airlines
Wed 12/316:00 amOPO - ONT
2 stops23h 07mUnited Airlines
Deal found 11/2$1,447
This United Airlines deal was found by Cheapflights users on 11/2. 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 12/231:40 pmONT - OPO
2 stops17h 05mUnited Airlines
Fri 1/96:00 amOPO - ONT
2 stops24h 53mUnited Airlines
Deal found 11/2$1,452
This United Airlines deal was found by Cheapflights users on 11/2. 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 11/207:00 amONT - OPO
2 stops18h 30mUnited Airlines
Mon 12/112:30 pmOPO - ONT
2 stops41h 19mUnited Airlines
Deal found 11/2$1,596
This United Airlines deal was found by Cheapflights users on 11/3. 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 12/231:40 pmONT - OPO
2 stops41h 45mUnited Airlines
Sat 1/36:00 amOPO - ONT
2 stops38h 38mUnited Airlines
Deal found 11/3$1,982
This Mytrip deal was found by Cheapflights users on 11/3. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/311:02 pmONT - OPO
3 stops32h 13mMultiple Airlines
Wed 12/108:05 pmOPO - ONT
3 stops32h 50mMultiple Airlines
Deal found 11/3$2,139
This Orbitz deal was found by Cheapflights users on 11/4. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/1810:50 amONT - OPO
2 stops16h 55mMultiple Airlines
Mon 1/58:20 amOPO - ONT
2 stops20h 38mMultiple Airlines
Deal found 11/4$3,918
This British Airways deal was found by Cheapflights users on 11/2. 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.
Tue 11/1812:46 pmONT - OPO
2 stops20h 59mBritish Airways
Tue 1/138:20 amOPO - ONT
2 stops22h 28mBritish Airways
Deal found 11/2$4,924

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 November 4, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$503
(United Airlines)

One-way from

$451
(United Airlines)

Popular in

December

Cheapest in

February

Average price

$722
Provider with most accurate pricing for Ontario-Porto flight deals.
Search Deals
Provider most trusted by Cheapflights users for Ontario-Porto flights.
Search Deals
From Ontario to Porto
Search Deals
One-way flight from Ontario to Porto
Search Deals
High demand for flights, 2% potential price rise
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($25 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in November 2025
Search Deals

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 November 4, 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

Wed 12/3

6:00 am-3:25 pm

2 stops25h 25m

Porto

Wed 12/10

6:00 am-5:37 pm

2 stops43h 37m

$503

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Thu 2/12

6:00 am-2:45 pm

2 stops24h 45m

Porto

Mon 2/16

12:30 pm-12:38 pm

2 stops56h 08m

$523

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Tue 2/3

6:00 am-10:30 am

2 stops20h 30m

Porto

Wed 3/4

4:10 pm-9:07 pm

2 stops36h 57m

$541

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Sun 2/1

6:00 am-10:30 am

2 stops20h 30m

Porto

Wed 3/4

11:15 am-11:53 pm

2 stops44h 38m

$542

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Tue 2/3

6:00 am-10:30 am

2 stops20h 30m

Porto

Thu 3/5

4:10 pm-4:04 pm

2 stops31h 54m

$542

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Sat 1/31

6:00 am-10:30 am

2 stops20h 30m

Porto

Tue 3/3

11:15 am-10:40 pm

2 stops43h 25m

$542

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Mon 2/2

10:30 pm-10:30 am

2 stops28h 00m

Porto

Tue 3/3

11:15 am-4:04 pm

2 stops36h 49m

$542

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Sat 1/31

6:00 am-10:30 am

2 stops20h 30m

Porto

Mon 3/2

6:30 am-4:04 pm

2 stops41h 34m

$542

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Sun 2/1

6:00 am-10:30 am

2 stops20h 30m

Porto

Mon 3/2

6:30 am-11:53 pm

2 stops49h 23m

$542

OntarioPorto

ONT - OPO

ONTOPO

Ontario

Tue 2/3

6:00 am-10:30 am

2 stops20h 30m

Porto

Wed 3/4

6:00 am-9:07 pm

2 stops23h 07m

$542

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/3

Showing 1-10 of 21 results
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Compare providers for flights from Ontario to Porto

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Ontario to Porto in November.
ProviderPrice AccuracyTrust Score*
eDreamsPrice Accuracy3 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
AranGrantPrice Accuracy2 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Ontario-Porto flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Ontario-Porto flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Ontario-Porto flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Ontario-Porto flights, Cheapflights users trust eDreams the most. eDreams has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Ontario-Porto flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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, May is the cheapest month in which you can book a flight from Ontario to Porto (average of $413). Flying from Ontario to Porto in June is currently the most expensive (average of $821). 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 November 4, 2025.

One of the essential ways to save on airfare from Ontario to Porto is to remain as flexible as possible. Flights that are at noon tend to be the most expensive. A flight in the evening could potentially save you up to 45% on airfare.

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, KLM, and Delta can get you from Ontario to Porto in just under 20h 30m. Your travel time can differ by up to 4h 55m. 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, May is the cheapest month in which you can book a flight from Ontario to Porto (average of $413). Flying from Ontario to Porto in June is currently the most expensive (average of $821). 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
Vila Nova de Gaia

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