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$363+ Cheap flights from Porto (OPO) to San Francisco (SFO)

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.
OPO — SFO
Jun 17 — Jun 241
Tue 6/17
Tue 6/24
1 adult, Economy
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Cheap flight deals from Porto to San Francisco

Discover tips and strategies to find the most affordable flight options for your journey from Porto (OPO) to San Francisco (SFO). 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 June 12, 2025.

Round-trip from

$613
(Gotogate)

One-way from

$363
(Kiwi.com)

Popular in

October

Cheapest in

February

Average price

$913
From Porto to San Francisco
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One-way flight from Porto to San Francisco
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Highest demand for flights based on searches. 13% potential increase in price ($132 potential increase over avg. RT price).
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Cheapest flight prices on average. 7% potential price decrease ($61 potential savings vs. average RT price).
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Average for round-trip flights in June 2025
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Find flight deals from Porto to San Francisco

Cheapest flights from Porto to San Francisco
Explore the most affordable flight options available from Porto to San Francisco. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 12, 2025.

This Gotogate deal was found by Cheapflights users on 6/12. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/610:35 pmOPO - SFO
1 stop23h 00mTAP AIR PORTUGAL
Sat 10/187:20 pmSFO - OPO
1 stop15h 40mTAP AIR PORTUGAL
Deal found 6/12$613
This American Airlines deal was found by Cheapflights users on 6/11. 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.
Thu 9/188:15 amOPO - SFO
2 stops20h 17mAmerican Airlines
Mon 9/226:10 amSFO - OPO
2 stops17h 25mAmerican Airlines
Deal found 6/11$634
This AirNGo deal was found by Cheapflights users on 6/12. 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 AirNGo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/64:20 pmOPO - SFO
1 stop27h 25mMultiple Airlines
Sat 10/181:00 pmSFO - OPO
2 stops18h 30mMultiple Airlines
Deal found 6/12$637
This Iberia deal was found by Cheapflights users on 6/11. 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.
Thu 6/198:15 amOPO - SFO
2 stops20h 43mIberia
Tue 7/225:45 pmSFO - OPO
1 stop14h 10mIberia
Deal found 6/11$697
This SWISS deal was found by Cheapflights users on 6/11. 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 SWISS is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/1812:15 pmOPO - SFO
1 stop35h 55mSWISS
Mon 9/222:20 pmSFO - OPO
2 stops19h 05mSWISS
Deal found 6/11$713
This KLM deal was found by Cheapflights users on 6/11. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/198:20 pmOPO - SFO
1 stop23h 25mKLM
Tue 7/223:05 pmSFO - OPO
1 stop16h 25mKLM
Deal found 6/11$743
This British Airways deal was found by Cheapflights users on 6/12. 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.
Fri 7/189:10 pmOPO - SFO
2 stops34h 38mBritish Airways
Mon 9/14:30 pmSFO - OPO
1 stop19h 20mBritish Airways
Deal found 6/12$745
This United Airlines deal was found by Cheapflights users on 6/10. 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 8/156:00 amOPO - SFO
2 stops32h 42mUnited Airlines
Fri 8/2911:10 pmSFO - OPO
2 stops26h 25mUnited Airlines
Deal found 6/10$761
This Delta deal was found by Cheapflights users on 6/11. 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.
Sat 7/269:20 amOPO - SFO
2 stops22h 59mDelta
Sat 8/210:55 amSFO - OPO
2 stops20h 40mDelta
Deal found 6/11$824
This Lufthansa deal was found by Cheapflights users on 6/11. 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 Lufthansa is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/276:15 amOPO - SFO
1 stop20h 45mLufthansa
Tue 7/19:05 pmSFO - OPO
1 stop18h 15mLufthansa
Deal found 6/11$1,005
This Air France deal was found by Cheapflights users on 6/11. 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 Air France is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/279:20 amOPO - SFO
2 stops20h 13mAir France
Tue 7/13:05 pmSFO - OPO
1 stop16h 25mAir France
Deal found 6/11$1,076
This Gotogate deal was found by Cheapflights users on 6/11. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 6/186:00 amOPO - SFO
2 stops23h 42mAir Canada
Wed 6/258:36 amSFO - OPO
2 stops16h 44mAir Canada
Deal found 6/11$1,269

Cheapflights Fare Finder

Customize your flight search to find flights from Porto to San Francisco 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 June 12, 2025.
Use the filters below to find and compare flights from Porto to San Francisco that are best for you.

Fly from

Porto

Fly to

San Francisco

Route

Depart

Return

Price

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Mon 10/6

10:35 pm-1:35 pm

1 stop23h 00m

San Francisco

Sat 10/18

7:20 pm-7:00 pm

1 stop15h 40m

$613

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Thu 9/18

8:15 am-8:32 pm

2 stops20h 17m

San Francisco

Mon 9/22

6:10 am-7:35 am

2 stops17h 25m

$634

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Mon 10/6

4:20 pm-11:45 am

1 stop27h 25m

San Francisco

Sat 10/18

1:00 pm-3:30 pm

2 stops18h 30m

$637

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Thu 9/18

12:15 pm-4:10 pm

1 stop35h 55m

San Francisco

Mon 9/22

2:20 pm-5:25 pm

2 stops19h 05m

$713

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Fri 7/18

9:10 pm-11:48 pm

2 stops34h 38m

San Francisco

Mon 9/1

4:30 pm-7:50 pm

1 stop19h 20m

$745

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Wed 6/25

8:15 am-9:27 pm

2 stops21h 12m

San Francisco

Tue 7/1

11:15 am-7:55 pm

2 stops24h 40m

$760

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Fri 8/15

6:00 am-6:42 am

2 stops32h 42m

San Francisco

Fri 8/29

11:10 pm-9:35 am

2 stops26h 25m

$761

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Sat 7/26

9:20 am-12:19 am

2 stops22h 59m

San Francisco

Sat 8/2

1:45 pm-6:10 pm

1 stop20h 25m

$806

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Wed 6/25

8:10 pm-11:45 am

1 stop23h 35m

San Francisco

Tue 7/1

3:05 pm-3:30 pm

1 stop16h 25m

$962

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Fri 6/27

6:15 am-7:00 pm

1 stop20h 45m

San Francisco

Tue 7/1

9:05 pm-11:20 pm

1 stop18h 15m

$1,005

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/11

Showing 1-10 of 22 results
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2
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Best time to book a flight from Porto to San Francisco

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

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

Currently, January is the cheapest month in which you can book a flight from Porto to San Francisco (average of $276). Flying from Porto to San Francisco in June is currently the most expensive (average of $364). 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 OPO to SFO?

Find hourly flight availability from Porto to San Francisco. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 12, 2025.

When flying from Porto to San Francisco, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

Rainfall in San Francisco by month

Plan your trip to San Francisco by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in San Francisco ranges from 0.0 - 4.4 inches per month. January is typically the wettest month, when rainfall can reach 4.4 in. July is typically the driest time to visit San Francisco when rainfall is around 0.0 in.

Temperature in San Francisco by month

Plan your trip to San Francisco by taking into account the average temperature totals by month.

If weather is an important factor for your trip to San Francisco, use this chart to help with planning. For those seeking warmer temperatures, September is the ideal time of year to visit, when temperatures reach an average of 62.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 51.8 F).

Reviews of airlines servicing San Francisco

Get insights into the airlines that provide service to San Francisco. 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 San Francisco. Reviews last updated June 12, 2025.
To help decide which airline to fly from Porto to San Francisco, see what other customers have to say about Delta, KLM and Air France. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,950 reviews

Food

7.3

Boarding

8.2

Comfort

7.9

Overall

8.0

Entertainment

7.9

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Delta
8.0
Very good
7,950 reviews
Delta
8.0
Very good
7,950 reviews

Food

7.3

Boarding

8.2

Comfort

7.9

Overall

8.0

Entertainment

7.9

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
KLM
7.8
Good
1,358 reviews
Delta
8.0
Very good
7,950 reviews

Food

7.3

Boarding

8.2

Comfort

7.9

Overall

8.0

Entertainment

7.9

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
Air France
7.5
Good
1,463 reviews
Delta
8.0
Very good
7,950 reviews

Food

7.3

Boarding

8.2

Comfort

7.9

Overall

8.0

Entertainment

7.9

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
SWISS
7.5
Good
1,623 reviews
Delta
8.0
Very good
7,950 reviews

Food

7.3

Boarding

8.2

Comfort

7.9

Overall

8.0

Entertainment

7.9

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception
United Airlines
7.4
Good
8,790 reviews
Delta
8.0
Very good
7,950 reviews

Food

7.3

Boarding

8.2

Comfort

7.9

Overall

8.0

Entertainment

7.9

Crew

8.5

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

TUS - LAX

Delta has consistently been the best U.S. airline for my travels and this flight was no exception

Related info for your journey

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

  • What are the cheapest airlines flying from Porto to San Francisco round-trip?

    Our cheapest airline available from Porto to San Francisco is TAP AIR PORTUGAL. Our recent data shows that you can find tickets from as low as $613 on this airline. Additional options worth looking into are American Airlines and SWISS, starting at $634 and $713 round-trip. These flights start at 29% lower than the current average price 3 months from now.

  • What are the cheapest airlines to fly from Porto to San Francisco one-way?

    The cheapest airlines for a one-way flight from Porto to San Francisco are Vueling ($401), Iberia ($413), and TAP AIR PORTUGAL ($518).

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

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

  • How can I find direct flights from Porto to San Francisco?

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

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

    Yes. Cheapflights offers flight deals from Porto to San Francisco 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 Porto to San Francisco?

    Currently, January is the cheapest month in which you can book a flight from Porto to San Francisco (average of $276). Flying from Porto to San Francisco in June is currently the most expensive (average of $364). 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
Roseville
Mountain View
South San Francisco
Livermore
Turlock
Santa Cruz
Manteca
Fairfield
Watsonville
Antioch
Hollister
Milpitas
Newark
Hayward
Alameda
Sunnyvale
Daly City
Union City
Campbell
Capitola

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 2 airlines flying from Porto to San Francisco

Discover the top 2 airlines that operate flights from Porto to San Francisco. 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 June 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$657Average$873FlexibilityNo cancel feeOn-time69%
LufthansaCheapest$665Average$898FlexibilityNo cancel feeOn-time76%

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