$404+ 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 9/15. Fares are subject to change and may not be available on all flights or dates of travel.
OPO — SFO
Aug 24 — Aug 311
Round-trip
1 adult, Economy
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Find cheap flights from Porto to San Francisco with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
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Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Porto to San Francisco
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Best
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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 July 25, 2026.
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 25, 2026.
This Iberia deal was found by Cheapflights users on 7/23. 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.
Mon 8/248:20 am
OPO
- SFO
1 stop16h 20m
Multiple Airlines
Tue 9/84:35 pm
SFO
- OPO
1 stop18h 55m
Multiple Airlines
Deal found 7/23![Multiple Airlines logo]()
$611
This Iberia deal was found by Cheapflights users on 7/25. 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.
Fri 8/2812:25 pm
OPO
- SFO
2 stops20h 29m
Multiple Airlines
Sun 9/134:35 pm
SFO
- OPO
1 stop20h 00m
Multiple Airlines
Deal found 7/25![Multiple Airlines logo]()
$615
This Iberia deal was found by Cheapflights users on 7/23. 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.
Sat 11/218:20 am
OPO
- SFO
2 stops19h 39m
Iberia
Mon 11/305:25 pm
SFO
- OPO
2 stops18h 35m
Iberia
Deal found 7/23![Iberia logo]()
$619
This Mytrip deal was found by Cheapflights users on 7/22. 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.
Tue 9/18:40 am
OPO
- SFO
1 stop15h 35m
SWISS
Mon 9/77:35 pm
SFO
- OPO
1 stop38h 00m
SWISS
Deal found 7/22![SWISS logo]()
$622
This American Airlines deal was found by Cheapflights users on 7/22. 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 8/248:20 am
OPO
- SFO
1 stop16h 20m
American Airlines
Tue 9/82:08 pm
SFO
- OPO
2 stops17h 52m
American Airlines
Deal found 7/22![American Airlines logo]()
$624
This Mytrip deal was found by Cheapflights users on 7/25. 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.
Fri 8/288:40 am
OPO
- SFO
1 stop15h 35m
SWISS
Sun 9/137:35 pm
SFO
- OPO
1 stop14h 40m
SWISS
Deal found 7/25![SWISS logo]()
$626
This American Airlines deal was found by Cheapflights users on 7/25. 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.
Tue 8/1112:25 pm
OPO
- SFO
2 stops28h 25m
American Airlines
Tue 8/2510:24 am
SFO
- OPO
2 stops17h 21m
American Airlines
Deal found 7/25![American Airlines logo]()
$627
This American Airlines deal was found by Cheapflights users on 7/24. 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 8/1312:25 pm
OPO
- SFO
2 stops19h 46m
American Airlines
Fri 8/2111:00 am
SFO
- OPO
2 stops21h 00m
American Airlines
Deal found 7/24![American Airlines logo]()
$628
Best flights from Porto to San FranciscoDiscover 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 July 25, 2026.
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 July 25, 2026.
This Iberia deal was found by Cheapflights users on 7/20. 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 Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/2812:25 pm
OPO
- SFO
2 stops20h 29m
Multiple Airlines
Sun 9/134:35 pm
SFO
- OPO
1 stop20h 00m
Multiple Airlines
Deal found 7/20![Multiple Airlines logo]()
$618
This Gotogate deal was found by Cheapflights users on 7/20. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/288:40 am
OPO
- SFO
1 stop15h 35m
SWISS
Sun 9/137:35 pm
SFO
- OPO
1 stop14h 40m
SWISS
Deal found 7/20![SWISS logo]()
$628
This United Airlines deal was found by Cheapflights users on 7/22. 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 12/226:00 am
OPO
- SFO
1 stop22h 10m
United Airlines
Fri 1/11:50 pm
SFO
- OPO
1 stop17h 30m
United Airlines
Deal found 7/22![United Airlines logo]()
$648
This United Airlines deal was found by Cheapflights users on 7/24. 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 11/512:35 pm
OPO
- SFO
1 stop32h 00m
United Airlines
Mon 11/912:05 pm
SFO
- OPO
1 stop13h 25m
United Airlines
Deal found 7/24![United Airlines logo]()
$661
This United Airlines deal was found by Cheapflights users on 7/25. 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 9/812:15 pm
OPO
- SFO
1 stop16h 32m
United Airlines
Tue 9/1511:39 pm
SFO
- OPO
1 stop23h 21m
United Airlines
Deal found 7/25![United Airlines logo]()
$671
This United Airlines deal was found by Cheapflights users on 7/24. 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 8/149:00 am
OPO
- SFO
1 stop18h 14m
United Airlines
Fri 8/2111:59 pm
SFO
- OPO
1 stop22h 56m
United Airlines
Deal found 7/24![United Airlines logo]()
$671
Last-minute flights from Porto to San FranciscoDiscover last-minute flight deals from Porto to San Francisco. Data last updated July 25, 2026 and is based on user searches.
Discover last-minute flight deals from Porto to San Francisco. Data last updated July 25, 2026 and is based on user searches.
This American Airlines deal was found by Cheapflights users on 7/25. 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.
Tue 8/1112:25 pm
OPO
- SFO
2 stops28h 25m
American Airlines
Fri 8/2811:30 pm
SFO
- OPO
2 stops32h 30m
American Airlines
Deal found 7/25![American Airlines logo]()
$627
This American Airlines deal was found by Cheapflights users on 7/23. 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.
Tue 8/118:20 am
OPO
- SFO
2 stops32h 30m
American Airlines
Mon 8/249:30 pm
SFO
- OPO
2 stops30h 15m
American Airlines
Deal found 7/23![American Airlines logo]()
$629
This American Airlines deal was found by Cheapflights users on 7/24. 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 8/1312:25 pm
OPO
- SFO
2 stops19h 46m
American Airlines
Fri 8/2111:00 am
SFO
- OPO
2 stops21h 00m
American Airlines
Deal found 7/24![American Airlines logo]()
$628
This Iberia deal was found by Cheapflights users on 7/23. 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.
Mon 8/248:20 am
OPO
- SFO
1 stop16h 20m
Multiple Airlines
Tue 9/84:35 pm
SFO
- OPO
1 stop18h 55m
Multiple Airlines
Deal found 7/23![Multiple Airlines logo]()
$611
This American Airlines deal was found by Cheapflights users on 7/22. 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 8/248:20 am
OPO
- SFO
1 stop16h 20m
American Airlines
Tue 9/82:08 pm
SFO
- OPO
2 stops17h 52m
American Airlines
Deal found 7/22![American Airlines logo]()
$624
This Iberia deal was found by Cheapflights users on 7/25. 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.
Fri 8/2812:25 pm
OPO
- SFO
2 stops20h 29m
Multiple Airlines
Sun 9/134:35 pm
SFO
- OPO
1 stop20h 00m
Multiple Airlines
Deal found 7/25![Multiple Airlines logo]()
$615
This Mytrip deal was found by Cheapflights users on 7/25. 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.
Fri 8/288:40 am
OPO
- SFO
1 stop15h 35m
SWISS
Sun 9/137:35 pm
SFO
- OPO
1 stop14h 40m
SWISS
Deal found 7/25![SWISS logo]()
$626
One-way flights from Porto to San FranciscoSearch for one-way flight options from Porto to San Francisco. Find affordable one-way fares based on user searches. Data last updated July 25, 2026.
Search for one-way flight options from Porto to San Francisco. Find affordable one-way fares based on user searches. Data last updated July 25, 2026.
This Kiwi.com deal was found by Cheapflights users on 7/24. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/159:30 pm
OPO
- SFO
2 stops25h 05m
Multiple Airlines
Deal found 7/24![Multiple Airlines logo]()
$404
This Kiwi.com deal was found by Cheapflights users on 7/24. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/162:40 pm
OPO
- SFO
2 stops31h 50m
Multiple Airlines
Deal found 7/24![Multiple Airlines logo]()
$410
This Kiwi.com deal was found by Cheapflights users on 7/23. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/1410:45 pm
OPO
- SFO
3 stops47h 50m
Multiple Airlines
Deal found 7/23![Multiple Airlines logo]()
$416
This Kiwi.com deal was found by Cheapflights users on 7/21. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/259:30 pm
OPO
- SFO
2 stops49h 00m
Multiple Airlines
Deal found 7/21![Multiple Airlines logo]()
$433
This Kiwi.com deal was found by Cheapflights users on 7/22. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/249:30 pm
OPO
- SFO
3 stops52h 50m
Multiple Airlines
Deal found 7/22![Multiple Airlines logo]()
$435
This Iberia deal was found by Cheapflights users on 7/22. 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 9/2412:25 pm
OPO
- SFO
2 stops20h 34m
Iberia
Deal found 7/22![Iberia logo]()
$436
This Iberia deal was found by Cheapflights users on 7/21. 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.
Fri 9/258:20 am
OPO
- SFO
2 stops23h 08m
Iberia
Deal found 7/21![Iberia logo]()
$437
Find 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 25, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $611 (Iberia) |
One-way from | $404 (Kiwi.com) |
Popular in | June |
Cheapest in | November |
Average price | $1,016 |
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 25, 2026.
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
Cheapest round-trip
PortoSan Francisco
OPO - SFO
OPOSFO
Porto
Fri 8/28
12:25 pm-12:54 am
2 stops20h 29m
San Francisco
Sun 9/13
4:35 pm-8:35 pm
1 stop20h 00m
$618
Quickest round-trip
PortoSan Francisco
OPO - SFO
OPOSFO
Porto
Fri 8/28
8:40 am-4:15 pm
1 stop15h 35m
San Francisco
Sun 9/13
7:35 pm-6:15 pm
1 stop14h 40m
$628
PortoSan Francisco
OPO - SFO
OPOSFO
Porto
Tue 12/22
6:00 am-8:10 pm
1 stop22h 10m
San Francisco
Fri 1/1
1:50 pm-3:20 pm
1 stop17h 30m
$648
PortoSan Francisco
OPO - SFO
OPOSFO
Porto
Thu 11/5
12:35 pm-12:35 pm
1 stop32h 00m
San Francisco
Mon 11/9
12:05 pm-9:30 am
1 stop13h 25m
$661
PortoSan Francisco
OPO - SFO
OPOSFO
Porto
Tue 9/8
12:15 pm-8:47 pm
1 stop16h 32m
San Francisco
Tue 9/15
11:39 pm-7:00 am
1 stop23h 21m
$671
PortoSan Francisco
OPO - SFO
OPOSFO
Porto
Fri 8/14
9:00 am-7:14 pm
1 stop18h 14m
San Francisco
Fri 8/21
11:59 pm-6:55 am
1 stop22h 56m
$671
Cheapest one-way
PortoSan Francisco
OPO - SFO
OPOSFO
Porto
Fri 11/6
10:20 am-8:10 pm
1 stop17h 50m
$516
PortoSan Francisco
OPO - SFO
OPOSFO
Porto
Tue 9/22
12:25 pm-11:28 pm
2 stops19h 03m
$553
PortoSan Francisco
OPO - SFO
OPOSFO
Porto
Sun 11/29
8:05 pm-2:55 pm
1 stop26h 50m
$561
PortoSan Francisco
OPO - SFO
OPOSFO
Porto
Thu 11/19
6:40 pm-2:55 pm
1 stop28h 15m
$561
Showing 1-10 of 17 resultsSorted by cheapest first
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 July.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star | |
| Price Accuracy1 star | Trust Score*1 star |
- Most accurate provider: When it comes to deals on Porto-San Francisco flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Porto-San Francisco flight deals on Cheapflights vs. FlightHub >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 FlightHub the most. FlightHub 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.
OPO-SFO
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, November is the cheapest month in which you can book a flight from Porto to San Francisco (average of $692). Flying from Porto to San Francisco in June is currently the most expensive (average of $1,154). 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?
Airfare is below average for this route at the moment.
Porto to San Francisco flights typically cost between $861 and $1,038 in August.The cheapest round-trip price found within the last 5 days was $611 on Multiple Airlines (Aug 24-Sep 8).
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 25, 2026.
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.
Boarding
7.0
Crew
7.6
Comfort
6.8
Food
6.3
Overall
6.8
Entertainment
6.4
Reviews
1 / 20
4.0
OkayDjermouli,Dec 2025
FRA - SFO
Boarding
7.0
Crew
7.6
Comfort
6.8
Food
6.3
Overall
6.8
Entertainment
6.4
Reviews
1 / 20
4.0
OkayDjermouli,Dec 2025
FRA - SFO
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.
Traveling to a place near San Francisco?
Book flights to San Francisco if you plan to visit one of these locationsSouth San Francisco
Santa Clara
Santa Cruz
Fairfield
Roseville
Burlingame
Rancho Cordova
San Bruno
Cupertino
Emeryville
Newark
Watsonville
Hayward
Redwood City
San Carlos
San Ramon
Turlock
Vallejo
San Lorenzo
Davis
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.
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Alternative routes for Porto to San Francisco
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Complete your trip
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Find flights from Porto to San Francisco, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Porto and San Francisco flights
Browse other Porto and San Francisco flight options. Last updated on July 25, 2026.
Other flights from Porto
Browse through other flights departing from Porto. Flights are based on user searches made on Cheapflights and were last updated on July 25, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Other flights to San Francisco
Explore flights to San Francisco departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on July 25, 2026.
Top airline flying from Porto to San Francisco
Discover the top airline 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 25, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$688 | Average$844 | FlexibilityNo cancel fee | On-time76% |