How long is the flight from Porto to San Francisco?

Airlines like KLM, SWISS, and United Airlines fly from Porto to San Francisco in about 22h 10m. The time it takes to get you to your destination can typically vary by up to 9h 50m. There are 5566 mi between Porto and San Francisco. This flight may include one or multiple stops.

What is the cheapest airline to fly from Porto to San Francisco round-trip?

Our cheapest airline available from Porto to San Francisco is Lufthansa. Our recent data shows that you can find tickets from as low as $670 on this airline. This flight start at 15% 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 Iberia ($412), TAP AIR PORTUGAL ($516), and SWISS ($625).

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.

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).

What is the cheapest time of day to fly from OPO to SFO?

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.

Most accurate provider : When it comes to deals on Porto-San Francisco flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Porto-San Francisco flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Porto-San Francisco flight searches over the past month and is updated monthly.

Most trusted provider : When it comes to deals on Porto-San Francisco 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 Porto-San Francisco flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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.

$426+ Flights from Porto to San Francisco

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Cheap 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 December 12, 2025.

Fri 12/2612:30 pmOPO - SFO

1 stop15h 40mLufthansa

Thu 1/81:30 pmSFO - OPO

1 stop15h 20mLufthansa

Deal found 12/11

$750

Fri 12/2612:30 pmOPO - SFO

1 stop15h 40mUnited Airlines

Fri 1/91:35 pmSFO - OPO

1 stop17h 10mUnited Airlines

Deal found 12/11

$766

Fri 12/2612:30 pmOPO - SFO

1 stop15h 40mUnited Airlines

Sat 1/101:40 pmSFO - OPO

2 stops38h 00mUnited Airlines

Deal found 12/11

$772

Thu 12/2511:15 amOPO - SFO

1 stop32h 35mDelta

Thu 1/810:55 pmSFO - OPO

2 stops27h 35mDelta

Deal found 12/11

$774

Thu 12/2511:15 amOPO - SFO

1 stop32h 35mDelta

Sat 1/1010:55 pmSFO - OPO

2 stops27h 35mDelta

Deal found 12/11

$775

Sun 12/214:15 pmOPO - SFO

1 stop28h 25mMultiple Airlines

Sat 1/107:25 pmSFO - OPO

1 stop15h 10mMultiple Airlines

Deal found 12/10

$777

Sun 12/214:15 pmOPO - SFO

1 stop28h 25mLufthansa

Fri 1/91:30 pmSFO - OPO

1 stop15h 20mLufthansa

Deal found 12/10

$784

Sun 12/214:15 pmOPO - SFO

1 stop28h 25mLufthansa

Wed 1/71:35 pmSFO - OPO

1 stop24h 50mLufthansa

Deal found 12/10

$785

Sun 12/2112:30 pmOPO - SFO

1 stop32h 10mUnited Airlines

Wed 1/71:40 pmSFO - OPO

2 stops38h 00mUnited Airlines

Deal found 12/10

$791

Fri 12/2611:15 amOPO - SFO

1 stop32h 35mDelta

Fri 1/97:00 amSFO - OPO

2 stops19h 30mDelta

Deal found 12/11

$793

Best flights from Porto to San Francisco
Discover carefully curated flight deals from Porto to San Francisco that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated December 12, 2025.

Fri 5/1511:45 amOPO - SFO

1 stop32h 00mKLM

Mon 5/183:05 pmSFO - OPO

1 stop16h 25mKLM

Deal found 12/9

$710

Sun 1/257:25 pmOPO - SFO

1 stop29h 05mSWISS

Sun 2/17:25 pmSFO - OPO

1 stop31h 50mSWISS

Deal found 12/11

$719

Fri 1/166:00 amOPO - SFO

1 stop22h 10mUnited Airlines

Mon 1/262:40 pmSFO - OPO

1 stop16h 15mUnited Airlines

Deal found 12/10

$744

Sat 1/1712:30 pmOPO - SFO

1 stop15h 40mLufthansa

Tue 1/271:35 pmSFO - OPO

1 stop24h 50mLufthansa

Deal found 12/10

$744

Thu 1/1512:05 pmOPO - SFO

1 stop36h 25mSWISS

Wed 1/287:25 pmSFO - OPO

1 stop31h 45mSWISS

Deal found 12/10

$726

Tue 1/206:00 amOPO - SFO

1 stop17h 55mUnited Airlines

Wed 1/282:40 pmSFO - OPO

1 stop16h 45mUnited Airlines

Deal found 12/10

$744

Tue 1/206:00 amOPO - SFO

1 stop17h 55mUnited Airlines

Thu 1/296:45 amSFO - OPO

2 stops24h 00mUnited Airlines

Deal found 12/10

$744

Fri 1/166:00 amOPO - SFO

1 stop22h 10mUnited Airlines

Sun 1/2511:20 pmSFO - OPO

2 stops31h 35mUnited Airlines

Deal found 12/10

$744

Fri 1/166:00 amOPO - SFO

1 stop22h 10mUnited Airlines

Thu 1/291:35 pmSFO - OPO

1 stop17h 10mUnited Airlines

Deal found 12/10

$744

Last-minute flights from Porto to San Francisco
Discover last-minute flight deals from Porto to San Francisco. Data last updated December 12, 2025 and is based on user searches.

Thu 1/1512:05 pmOPO - SFO

1 stop36h 25mSWISS

Wed 1/287:25 pmSFO - OPO

1 stop31h 45mSWISS

Deal found 12/10

$726

Thu 1/156:00 amOPO - SFO

2 stops36h 54mMultiple Airlines

Wed 1/287:25 pmSFO - OPO

1 stop31h 45mMultiple Airlines

Deal found 12/10

$742

Fri 1/166:00 amOPO - SFO

1 stop22h 10mUnited Airlines

Wed 1/286:45 amSFO - OPO

2 stops20h 55mUnited Airlines

Deal found 12/10

$744

Sat 1/176:55 amOPO - SFO

1 stop15h 50mTAP AIR PORTUGAL

Wed 1/284:35 pmSFO - OPO

1 stop14h 30mTAP AIR PORTUGAL

Deal found 12/10

$623

Sat 1/176:55 amOPO - SFO

1 stop15h 50mTAP AIR PORTUGAL

Sat 1/244:35 pmSFO - OPO

1 stop14h 25mTAP AIR PORTUGAL

Deal found 12/10

$627

Sat 1/176:00 amOPO - SFO

2 stops23h 39mMultiple Airlines

Sat 1/247:25 pmSFO - OPO

1 stop31h 45mMultiple Airlines

Deal found 12/10

$734

Sat 1/176:00 amOPO - SFO

1 stop22h 10mLufthansa

Tue 1/278:25 amSFO - OPO

2 stops20h 25mLufthansa

Deal found 12/10

$743

Fri 1/236:00 pmOPO - SFO

1 stop28h 45mTAP AIR PORTUGAL

Fri 1/307:10 pmSFO - OPO

1 stop14h 50mTAP AIR PORTUGAL

Deal found 12/10

$620

Sat 1/246:55 amOPO - SFO

1 stop15h 50mTAP AIR PORTUGAL

Sat 1/314:35 pmSFO - OPO

1 stop16h 25mTAP AIR PORTUGAL

Deal found 12/10

$633

Sun 1/2512:00 pmOPO - SFO

3 stops34h 35mMultiple Airlines

Sun 2/14:40 pmSFO - OPO

2 stops22h 20mMultiple Airlines

Deal found 12/11

$684

Sun 1/257:25 pmOPO - SFO

1 stop29h 05mSWISS

Sun 2/17:25 pmSFO - OPO

1 stop31h 50mSWISS

Deal found 12/11

$719

One-way flights from Porto to San Francisco
Search for one-way flight options from Porto to San Francisco. Find affordable one-way fares based on user searches. Data last updated December 12, 2025.

Thu 6/45:05 amOPO - SFO

2 stops20h 55mMultiple Airlines

Deal found 12/10

$426

Tue 1/138:25 amOPO - SFO

2 stops38h 05mMultiple Airlines

Deal found 12/10

$450

Wed 6/107:35 pmOPO - SFO

1 stop30h 25mMultiple Airlines

Deal found 12/9

$462

Tue 3/248:20 amOPO - SFO

2 stops23h 32mIberia

Deal found 12/11

$468

Thu 1/82:45 pmOPO - SFO

3 stops54h 46mMultiple Airlines

Deal found 12/10

$564

Wed 3/2512:40 pmOPO - SFO

2 stops29h 03mMultiple Airlines

Deal found 12/11

$565

Tue 1/138:00 pmOPO - SFO

1 stop26h 30mTAP AIR PORTUGAL

Deal found 12/10

$597

Find flight deals from Porto to San Francisco

Most accurate provider	eDreams 3 stars
Most trusted provider	eDreams 3 stars
Round-trip from	$620 (oojo)
One-way from	$426 (Kiwi.com)
Popular in	October
Cheapest in	September
Average price	$771

Provider with most accurate pricing for Porto-San Francisco flight deals.

Search Deals

Provider most trusted by Cheapflights users for Porto-San Francisco flights.

Search Deals

From Porto to San Francisco

Search Deals

One-way flight from Porto to San Francisco

Search Deals

High demand for flights, 4% potential price rise

Search Deals

Cheapest flight prices on average. 1% potential price decrease ($10 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in December 2025

Search Deals

Cheapflights Fare Finder

Use the filters below to find and compare flights from Porto to San Francisco that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Fri 5/15

11:45 am-11:45 am

1 stop32h 00m

San Francisco

Mon 5/18

3:05 pm-3:30 pm

1 stop16h 25m

$710

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Sun 1/25

7:25 pm-4:30 pm

1 stop29h 05m

San Francisco

Sun 2/1

7:25 pm-11:15 am

1 stop31h 50m

$719

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Thu 1/15

12:05 pm-4:30 pm

1 stop36h 25m

San Francisco

Wed 1/28

7:25 pm-11:10 am

1 stop31h 45m

$726

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Fri 1/16

6:00 am-8:10 pm

1 stop22h 10m

San Francisco

Mon 1/26

2:40 pm-2:55 pm

1 stop16h 15m

$744

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Sat 1/17

12:30 pm-8:10 pm

1 stop15h 40m

San Francisco

Tue 1/27

1:35 pm-10:25 pm

1 stop24h 50m

$744

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Tue 1/20

6:00 am-3:55 pm

1 stop17h 55m

San Francisco

Wed 1/28

2:40 pm-3:25 pm

1 stop16h 45m

$744

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Tue 1/20

6:00 am-3:55 pm

1 stop17h 55m

San Francisco

Thu 1/29

6:45 am-2:45 pm

2 stops24h 00m

$744

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Fri 1/16

6:00 am-8:10 pm

1 stop22h 10m

San Francisco

Sun 1/25

11:20 pm-2:55 pm

2 stops31h 35m

$744

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Fri 1/16

6:00 am-8:10 pm

1 stop22h 10m

San Francisco

Thu 1/29

1:35 pm-2:45 pm

1 stop17h 10m

$744

PortoSan Francisco

OPO - SFO

OPOSFO

Porto

Tue 3/24

8:20 am-12:52 am

2 stops23h 32m

$468

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/10

Showing 1-10 of 16 results

Compare providers for flights from Porto to San Francisco

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Porto to San Francisco in December.

Provider	Price Accuracy	Trust Score*
FlightHub	Price Accuracy3 stars	Trust Score*1 star
eDreams	Price Accuracy3 stars	Trust 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 Porto-San Francisco flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Porto-San Francisco flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Porto-San Francisco flight searches over the past month and is updated monthly.
Most trusted provider: When it comes to deals on Porto-San Francisco 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 Porto-San Francisco 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 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 $552). Flying from Porto to San Francisco in July is currently the most expensive (average of $824). 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.

Reviews of airlines servicing San Francisco

Peruse reviews from past customers who have flown with Lufthansa 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.

Lufthansa

6.8

Okay

7,626 reviews

Reviews

1 / 20

4.0

Okay

Djermouli,Dec 2025

FRA - SFO

I’m sorry the worst airline united food sales I’m diabetic plus high cholesterol pls seats it’s not comfortable plus screen tv broke I try to charge my phone don’t work I’m not flying with united airlines

Lufthansa

6.8

Okay

7,626 reviews

Lufthansa

6.8

Okay

7,626 reviews

Reviews

1 / 20

4.0

Okay

Djermouli,Dec 2025

FRA - SFO

Related info for your journey

How long is the flight from Porto to San Francisco?
Airlines like KLM, SWISS, and United Airlines fly from Porto to San Francisco in about 22h 10m. The time it takes to get you to your destination can typically vary by up to 9h 50m. There are 5566 mi between Porto and San Francisco. This flight may include one or multiple stops.
What is the cheapest airline to fly from Porto to San Francisco round-trip?
Our cheapest airline available from Porto to San Francisco is Lufthansa. Our recent data shows that you can find tickets from as low as $670 on this airline. This flight start at 15% 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 Iberia ($412), TAP AIR PORTUGAL ($516), and SWISS ($625).
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 $552). Flying from Porto to San Francisco in July is currently the most expensive (average of $824). 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

Roseville

South San Francisco

Santa Cruz

Livermore

Turlock

Manteca

Watsonville

Sunnyvale

Santa Clara

San Bruno

Redwood City

Daly City

Vallejo

Hollister

Foster City

Union City

Davis

San Ramon

Burlingame

Milpitas

Browse thousands of different options on Cheapflights for your next trip

Top airline flying from Porto to San Francisco

Airline	Cheapest	Average	Flexibility	On-time
Lufthansa	Cheapest$670	Average$844	FlexibilityNo cancel fee	On-time76%

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$426+ 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 6/4. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Porto to San Francisco with Cheapflights

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Cheap flight deals from Porto to San Francisco

Cheapest flights from Porto to San FranciscoExplore 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 December 12, 2025.

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 December 12, 2025.

Find flight deals from Porto to San Francisco

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Cheapflights Fare Finder

Use the filters below to find and compare flights from Porto to San Francisco that are best for you.

Compare providers for flights from Porto to San Francisco

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 Porto to San Francisco in December.

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.

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?

Reviews of airlines servicing San Francisco

Peruse reviews from past customers who have flown with Lufthansa 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.

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.

How long is the flight from Porto to San Francisco?

What is the cheapest airline to fly from Porto to San Francisco round-trip?

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

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

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

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

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

Traveling to a place near San Francisco?

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Porto to San Francisco

See prices for flight routes from nearby airports that may be better suited for you.

Top airline flying from Porto to San Francisco

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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 December 12, 2025.