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$379+ 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
Aug 3 — Aug 101
Sun 8/3
Sun 8/10
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 July 29, 2025.

Round-trip from

$620
(oojo)

One-way from

$379
(Mytrip)

Popular in

October

Cheapest in

February

Average price

$869
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. 14% potential increase in price ($140 potential increase over avg. RT price).
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Cheapest flight prices on average. 7% potential price decrease ($63 potential savings vs. average RT price).
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Average for round-trip flights in July 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 July 29, 2025.

This oojo deal was found by Cheapflights users on 7/28. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/226:55 amOPO - SFO
1 stop15h 50mTAP AIR PORTUGAL
Sat 11/294:35 pmSFO - OPO
1 stop14h 25mTAP AIR PORTUGAL
Deal found 7/28$620
This FlightHub deal was found by Cheapflights users on 7/28. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/215:45 pmOPO - SFO
1 stop28h 50mScandinavian Airlines
Sun 11/304:40 pmSFO - OPO
1 stop16h 05mScandinavian Airlines
Deal found 7/28$642
This Booking.com deal was found by Cheapflights users on 7/29. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/288:40 amOPO - SFO
1 stop15h 30mMultiple Airlines
Wed 9/1011:40 amSFO - OPO
1 stop13h 40mMultiple Airlines
Deal found 7/29$681
This Lufthansa deal was found by Cheapflights users on 7/28. 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.
Thu 8/286:15 amOPO - SFO
1 stop20h 45mLufthansa
Wed 9/107:00 amSFO - OPO
1 stop15h 05mLufthansa
Deal found 7/28$701
This Delta deal was found by Cheapflights users on 7/29. 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.
Thu 8/286:30 amOPO - SFO
2 stops21h 36mDelta
Wed 9/109:10 amSFO - OPO
2 stops22h 20mDelta
Deal found 7/29$706
This lol.travel deal was found by Cheapflights users on 7/27. 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 lol.travel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/1112:10 pmOPO - SFO
1 stop31h 01mUnited Airlines
Tue 9/236:00 amSFO - OPO
2 stops17h 45mUnited Airlines
Deal found 7/27$707
This Expedia deal was found by Cheapflights users on 7/27. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/1112:20 pmOPO - SFO
2 stops19h 55mIberia
Tue 9/238:00 amSFO - OPO
2 stops19h 40mIberia
Deal found 7/27$720
This KLM deal was found by Cheapflights users on 7/28. 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.
Sun 11/2311:25 amOPO - SFO
2 stops18h 48mAir France
Sat 11/293:50 pmSFO - OPO
1 stop34h 40mAir France
Deal found 7/28$724
This SWISS deal was found by Cheapflights users on 7/28. 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.
Fri 9/127:20 pmOPO - SFO
2 stops32h 50mSWISS
Fri 9/194:05 pmSFO - OPO
2 stops55h 15mSWISS
Deal found 7/28$811

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 July 29, 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

Sat 11/22

6:55 am-2:45 pm

1 stop15h 50m

San Francisco

Sat 11/29

4:35 pm-3:00 pm

1 stop14h 25m

$620

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Fri 11/21

5:45 pm-2:35 pm

1 stop28h 50m

San Francisco

Sun 11/30

4:40 pm-4:45 pm

1 stop16h 05m

$642

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Thu 8/28

8:40 am-4:10 pm

1 stop15h 30m

San Francisco

Wed 9/10

11:40 am-9:20 am

1 stop13h 40m

$681

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Thu 8/28

6:15 am-7:00 pm

1 stop20h 45m

San Francisco

Wed 9/10

7:00 am-6:05 am

1 stop15h 05m

$701

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Thu 8/28

6:30 am-8:06 pm

2 stops21h 36m

San Francisco

Wed 9/10

9:10 am-3:30 pm

2 stops22h 20m

$706

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Thu 9/11

12:10 pm-11:11 am

1 stop31h 01m

San Francisco

Tue 9/23

6:00 am-7:45 am

2 stops17h 45m

$707

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Thu 9/11

12:20 pm-12:15 am

2 stops19h 55m

San Francisco

Tue 9/23

8:00 am-11:40 am

2 stops19h 40m

$720

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Sun 11/23

11:25 am-10:13 pm

2 stops18h 48m

San Francisco

Sat 11/29

3:50 pm-10:30 am

1 stop34h 40m

$724

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Fri 9/12

7:20 pm-8:10 pm

2 stops32h 50m

San Francisco

Fri 9/19

4:05 pm-7:20 am

2 stops55h 15m

$811

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Tue 9/9

10:50 pm-2:35 pm

2 stops23h 45m

$379

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/27

Showing 1-10 of 20 results
1
2

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 $358). 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.

How much does it cost to fly round-trip from Porto to San Francisco?

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 July 29, 2025.
Peruse reviews from past customers who have flown with Delta, KLM, and Air Transat from Porto to San Francisco to help guide your decision. 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
7,979 reviews

Comfort

7.9

Boarding

8.2

Overall

8.0

Entertainment

7.9

Food

7.3

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
7,979 reviews
Delta
8.0
Very good
7,979 reviews

Comfort

7.9

Boarding

8.2

Overall

8.0

Entertainment

7.9

Food

7.3

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
1,383 reviews
Delta
8.0
Very good
7,979 reviews

Comfort

7.9

Boarding

8.2

Overall

8.0

Entertainment

7.9

Food

7.3

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 Transat
7.7
Good
424 reviews
Delta
8.0
Very good
7,979 reviews

Comfort

7.9

Boarding

8.2

Overall

8.0

Entertainment

7.9

Food

7.3

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
Austrian Airlines
7.6
Good
821 reviews
Delta
8.0
Very good
7,979 reviews

Comfort

7.9

Boarding

8.2

Overall

8.0

Entertainment

7.9

Food

7.3

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
1,465 reviews
Delta
8.0
Very good
7,979 reviews

Comfort

7.9

Boarding

8.2

Overall

8.0

Entertainment

7.9

Food

7.3

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 $620 on this airline. Additional options worth looking into are Scandinavian Airlines and Lufthansa, starting at $642 and $701 round-trip. These flights start at 27% 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 LEVEL ($457), Iberia ($530), and TAP AIR PORTUGAL ($543).

  • 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 $358). 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 San Francisco?

Book flights to San Francisco if you plan to visit one of these locations
Roseville
Mountain View
Santa Cruz
South San Francisco
Livermore
Turlock
Manteca
Antioch
Hollister
Watsonville
Sunnyvale
Newark
Milpitas
Campbell
Foster City
Capitola
Santa Clara
San Leandro
Burlingame
Redwood City

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 July 29, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$657Average$873FlexibilityNo cancel feeOn-time69%
LufthansaCheapest$665Average$882FlexibilityNo cancel feeOn-time76%

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