SFO - OPO

$270 Find Cheap Flights from San Francisco to Porto

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from San Francisco to Porto departing on 10/15. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy

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These are the airlines KAYAK users have selected most often from within our search results in flight searches from San Francisco to Porto.
These are the airlines KAYAK users have selected most often from within our search results in flight searches from San Francisco to Porto.
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Flight Deals

Cheap Flights from San Francisco to Porto (SFO-OPO)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from San Francisco to Porto that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from San Francisco to Porto

Tue, Sep 9 - Tue, Sep 23
TAP AIR PORTUGAL Logo
6:45 pm - 10:45 pmSFO-OPO
20h 00m2 stops
TAP AIR PORTUGAL Logo
10:30 pm - 2:35 pmOPO-SFO
24h 05m1 stop
$574TAP AIR PORTUGAL
Find Deal
Tue, Oct 7 - Wed, Oct 15
TAP AIR PORTUGAL Logo
4:20 pm - 5:00 pmSFO-OPO
16h 40m1 stop
TAP AIR PORTUGAL Logo
7:00 am - 2:35 pmOPO-SFO
15h 35m1 stop
$575TAP AIR PORTUGAL
Find Deal
Sat, Nov 1 - Fri, Nov 14
TAP AIR PORTUGAL Logo
5:35 pm - 3:00 pmSFO-OPO
14h 25m1 stop
TAP AIR PORTUGAL Logo
6:55 am - 4:05 pmOPO-SFO
17h 10m1 stop
$576TAP AIR PORTUGAL
Find Deal
Sat, Nov 1 - Fri, Nov 14
United Airlines Logo
10:59 pm - 9:30 amSFO-OPO
27h 31m2 stops
United Airlines Logo
12:30 pm - 8:10 pmOPO-SFO
15h 40m1 stop
$590United Airlines
Find Deal
Wed, Nov 12 - Wed, Nov 26
United Airlines Logo
8:30 am - 9:30 amSFO-OPO
17h 00m2 stops
United Airlines Logo
6:00 am - 8:57 pmOPO-SFO
22h 57m2 stops
$594United Airlines
Find Deal
Wed, Oct 22 - Mon, Nov 3
Iberia Logo
6:51 am - 3:55 pmSFO-OPO
25h 04m2 stops
Iberia Logo
8:40 pm - 9:26 amOPO-SFO
20h 46m2 stops
$608Iberia
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Wed, Oct 22 - Mon, Nov 3
SWISS Logo
7:30 pm - 6:30 pmSFO-OPO
15h 00m1 stop
SWISS Logo
9:10 am - 4:30 pmOPO-SFO
39h 20m2 stops
$635SWISS
Find Deal
Tue, Oct 14 - Wed, Oct 22
Lufthansa Logo
9:05 pm - 11:20 pmSFO-OPO
18h 15m1 stop
Lufthansa Logo
6:15 am - 7:40 pmOPO-SFO
21h 25m2 stops
$686Lufthansa
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Sat, Jan 17 - Sun, Jan 25
SWISS Logo
7:25 pm - 11:10 amSFO-OPO
31h 45m1 stop
SWISS Logo
4:10 pm - 4:30 pmOPO-SFO
56h 20m2 stops
$698SWISS
Find Deal
Sat, Oct 18 - Mon, Oct 27
Iberia Logo
11:59 pm - 7:35 amSFO-OPO
23h 36m2 stops
Iberia Logo
8:40 pm - 10:59 pmOPO-SFO
33h 19m2 stops
$699Iberia
Find Deal
Booking Insights

KAYAK's insights & trends for San Francisco to Porto flights

Get data-powered insights and trends into flights from San Francisco to Porto to help you find the cheapest flights, the best time to fly and much more.

What’s the cheapest day of the week to fly from San Francisco to Porto?

The average price of all round-trip flights from San Francisco to Porto clicked on KAYAK for each day over the last 12 months.

If your flying dates are flexible, you should consider flying to Porto on a Thursday, as we generally find the cheapest rates on that day for this route. On the other hand, Wednesday is the most expensive day to fly from San Francisco to Porto. For your return ticket, we recommend flying on a Wednesday and avoiding Saturdays for the best deals.

What is the cheapest month to fly from San Francisco to Porto?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from San Francisco to Porto, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from San Francisco to Porto is January, where tickets cost $678 (return) on average. On the other hand, the most expensive months are July and June, where the average cost of round-trip tickets is $1,188 and $1,178 respectively.

How far in advance should I book a flight from San Francisco to Porto?

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from San Francisco to Porto, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from San Francisco to Porto, you should book around 3 weeks before departure, which saves you about 13% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 13 weeks before departure.

Good to know

Low seasonDecember
Cheapest flight$270
Best time to beat the crowds but there is an average 11% increase in price.
Most popular time to fly with an average 23% increase in price.
Flight from San Francisco to Porto

When to book flights from San Francisco to Porto

Are your dates flexible? Find out the best times to travel from San Francisco to Porto based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from San Francisco to Porto

  • Which other cities can I visit after deplaning from my San Francisco to Porto flight at Francisco Sá Carneiro (OPO)?

    Porto's Francisco Sa Carneiro Airport (OPO) serves as the entry point for the entire region of northern Portugal. If you want to travel to other towns like Braga, renowned for its religious history and architecture, or Coimbra, renowned for having a well-preserved medieval town inside its boundaries, you may fly into OPO.

  • Can I rent a car for my movement flexibility after deplaning from my San Francisco to Porto flight at Francisco Sá Carneiro (OPO)?

    With OPO's Arrivals Hall hosting a number of car rental agencies' counters, you will find it easy to rent a car for your movement flexibility within and outside Porto. Among the car rental agencies with a car rental booth at OPO are SIXT, Budget, Hertz, and Avis.

  • How can I connect to the city after deplaning from my San Francisco to Porto flight at Francisco Sá Carneiro (OPO)?

    After deplaning from your San Francisco to Porto flight at OPO, you will connect to the city center via Metro Line E, a rental car, a bus, or a taxi. However, you should note that a bus travels between the airport and the city center throughout the night. Also, inquire about the toll pass if you're renting a car.

  • Which eco-friendly airline should I consider for my San Francisco to Porto flight?

    One of the eco-friendly airlines you should consider for your flight from San Francisco to Porto is KLM. The airline has made significant efforts to become more eco-friendly. It has implemented sustainable fuel initiatives, reduced emissions through efficient aircraft operations, and invested in carbon offset programs.

  • What is the cheapest flight from San Francisco to Porto?

    In the last 3 days, the lowest price for a flight from San Francisco to Porto was $270 for a one-way ticket and $574 for a round-trip.

  • Do I need a passport to fly between San Francisco and Porto?

    Yes

  • Which airports will I be using when flying from San Francisco to Porto?

    On your way to Porto, you’ll fly out from San Francisco. You’ll be landing at Porto.

  • Which aircraft models fly most regularly from San Francisco to Porto?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from San Francisco to Porto?

    oneworld, Star Alliance, and SkyTeam are the airline alliances operating flights between San Francisco and Porto, with Star Alliance being the most commonly used for this route.

  • What is the most popular layover when flying to Porto from San Francisco?

    Lisbon is the most popular layover city among KAYAK users traveling from San Francisco to Porto.

  • Which is the best airline for flights from San Francisco to Porto, SWISS or United Airlines?

    The two airlines most popular with KAYAK users for flights from San Francisco to Porto are SWISS and United Airlines. With an average price for the route of $977 and an overall rating of 7.5, SWISS is the most popular choice. United Airlines is also a great choice for the route, with an average price of $1,020 and an overall rating of 7.4.

  • How does KAYAK find such low prices on flights from San Francisco to Porto?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from San Francisco to Porto.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from San Francisco to Porto?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Porto from San Francisco is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from San Francisco to Porto?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Porto with an airline and back to San Francisco with another airline. Booking your flights between San Francisco and OPO can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from San Francisco to Porto?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Porto from San Francisco up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

KAYAK’s top tips for finding a cheap flight from San Francisco to Porto

  • When planning your flight from San Francisco to Porto, include at least a single layover. Most airlines servicing this route would make at least one stop before you could land at Francisco Sá Carneiro (OPO). Some of the common layovers on this route include Amsterdam Airport Schiphol (AMS), Adolfo Suárez Madrid-Barajas Airport (MAD), and Dallas/Fort Worth (DFW).
  • If you plan to travel with your pet from San Francisco to Porto, prioritize booking your flight with Delta Airlines. The airline's pet-friendly would allow you to travel with your caged dog or cat in the cabin provided it can fit under the chair. Larger pets would travel as cargo. You should, however, note that your pet will attract some extra charges. You will also need to present a current health certificate issued by a veterinarian.
  • One of the advantages of considering British Airways for your flight from San Francisco to Porto is its ticket upgrading benefits. During your first layover, the airline may send an email requesting to upgrade your ticket and enjoy the first-class amenities at a discounted price.
  • Although all airlines consider Persons with Reduced Mobility (PRMs), you should prioritize booking your flight ticket with Air France. To ensure comfort and enhanced access, the airline offers priority for PRMs, complimentary wheelchair access in SFO and OPO ticket counters, and a team of well-trained staff to care for PRMs' needs.
  • One of the airlines travelers with kids should consider for their flight from San Francisco to Porto is SWISS. To ensure a pleasant journey for your little ones, the airline may offer children's meals, kid-friendly entertainment options, and special toys or coloring books to keep them engaged throughout the flight.

Reviews of the top 5 airlines serving from San Francisco to Porto

 
See real verified KAYAK customer reviews for airlines flying from San Francisco to Porto. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from San Francisco to Porto? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.8
KLMOverall score based on 1384 reviews
7.8Boarding
7.7Comfort
7.3Food
7.1Entertainment
8.4Crew
Airline reviews

Short flight so it was okay. Nice crew, all very pleasant and professional. We were near the back in row 27 so just as we got our drinks, we started our descent so had to drink very quickly!

8.0 ExcellentMark, Aug 2025BHX - AMS
Read more KLM reviews

Short flight so it was okay. Nice crew, all very pleasant and professional. We were near the back in row 27 so just as we got our drinks, we started our descent so had to drink very quickly!

KLM remains a quality flag carrier airline which maintains its standards whilst all their competitors are lowering theirs.

The baggage drop-off in Stuttgart is bad: after online check-in you cannot use the automated baggage drop off as indicated on the website. You can use the terminals but have to cue to 1 of three open and slowly working counters to drop the bags. took about 45 minutes wait time.

My flight was delayed by 6 hours then I missed BOTH of my connecting flights, I then had to stay in the AIRPORT at JFK because soooooo many people also suffered from missing flights and there was no hotels available. I would like to be compensated for this experience! I had to stay in the airport for over 16 hours!

The service was great. However the lounge only gets passing grade

Cabin crew professional, polite and friendly, boarding was seemless, but come on KLM surely you can do better than a pack of cheesy biscuits as an inflight snack

Cabin crew were excellent, very proffesional, polite and friendly, in flight snack was underwhelming, a packet of cheese biscuits, im sure KLM could run to a sandwich!

You should not have to pay for WiFi in business class

Transfer at Amsterdam airport is very convenient and the airport is easy to navigate. Boarding was also quick and easy. Cabin crew were excellent and the meals were good, although lacking in options.

Overall very positive. Boarding was quick and organized. Cabin was clean and seats were reasonably comfortable. Cabin crew was excellent and the meals provided were also of good quality

horrible.. they cause such a problem and my daughter 14 years old was stranded in san francisco

I can’t even the whole trip was a catastrophe

Poor. Seats uncomfortable. No leg room. Hot and humid the whole trip. Food and staffs were ok.

The seats were so close together, when the man in front of me put his seat back, the screen in front of me was 9 inches from my face. There is no way to lean forward if I needed to pick something up. It was pretty uncomfortable for a ten hour flight. I was very surprised.

The food was good. Most the staff was pleasant. The flight would be drastically improved with WiFi on a long international flight.

When I needed to get my bag off of the plane so that I could take a train because the connection was 4 hours later, they took 2 hours to take my bag off making me take the train and miss my flight simultaneously. The seat size on the plane is too small for an average aged woman let alone a middle-aged man. It's unacceptable and I will not fly Boeing again.

The flight was generally good but was delayed departure meant a very late arrival for a connecting flight.

The cushion of the seats are old and very thin. The food can be more tasty or come with salt packages

The biggest let down was with booking experience through Kayak. I booked a flight with checked bags on Kayak. Right away I got a message from travel agency that the flight is not confirmed and to call them. I called them and they said the flight I have booked is no longer available with the price I have booked it for and I can book it with about $100 more. I already had other options I could book with cheaper price so I asked them to cancel my booking. Then they said I can have the ticket with the same price but a date change which was not working for me as I had to be there for a seminar. So again I said no then they said they will cover the charges and confirm my flight. When comes time for check-in I see I have no checked bag option which means the travel agency deceived me saying I can have my booking as I had booked it. And at that point I ended up paying $155 for my checked bag going back and forth. I am extremely angry and unhappy with this experience

PLEASE DONT TAKE FORCEFULLY(SIZE APPROPRIATE) CARRY ONS FROM PASSENGERS WHO FOR SOME REASON NEED TO KEEP IT

The pilots were late and it made us 1 hour late. The meat was tough and bok choy was also tough.

Stuck on tarmac for two hours plus a 5.5 hour flight. Rude flight attendant. And no meals, not even for purchase!

I learned that seating towards the end of plane that a line forms for the restroom and people use your chair as a hand railing, bumping your seat consistently. I was seated in the aisle. I think that next time if I am towards the back row I would want to sit in the middle or window seat.

The best airline I have ever travel , really good customer service, attention and service !!

Everything was great. Only thing that could’ve made it better was buy on board options for hot food, but the snacks were decent. The flight attendants were great. I had no complaints. I was able to make it to my destination safely

Horrific. They missed my connecting flight to San Diego. I didn’t get there until Monday at 9am when I had a mandatory court settlement conference scheduled at 6am since we had parties on the east coast. This caused many issues. All because United apparently forgot to hold the doors open until my flight landed that only had a 10 minute delay. This was the last flight to Southern California. So I couldn’t even rent a car to finish the trip. United cannot be trusted when traveling on specific days and times since weather didn’t have anything to do with the delays.

Very comfortable (upgraded to business class). The audio on my screen didn’t work, but I managed to play the audio through my phone while watching the screen.

Flight was late as pilot crew had to land at different airport in their previous flight. Passengers boarded and had to wait for pilots inside plane. Series of incomplete and unnecessary announcements by an annoying voice, rather than complete, informative announcements.

Breakfast was not loaded at SFO due to catering company change. Seems like a major airline at a major hub would have thought of something else or warned passengers to pick up food before boarding a 3 hour flight.

Boarding seemed to be organized bedlam. For what ever reason, preboarding took longer than 20 minutes. Made the plane 20 minutes late taking off. Luckily we arrived on time. Flight crew seemed very friendly. Only slight turbulence.

A good, comfortable flight with friendly crew and good entertainment options.

Very rude person at the boarding desk; flight attendant coughing 3 inches from my face three times- not even covering her mouth; boarding process very unacceptable for older people with stairs to all planes (are you all stuck in the 1960’s?). I am sure that I am not remembering all of the negative things, but I am sure you get the message!

There was chaos at the Naples airport. We arrived three hours early for the flight but there was no invitation available about where to go to check bags until an hour later. Then we had to go to a different terminal to check our bags and check in and back to the first to board.

We flew TAP last October from Newark to Lisbon. The meal was bad. This flight had good food. Also, this flight was delayed. There were TAP employees waiting at Lisbon to make sure we made our connecting flight. I find the TAP website and app frustrating, but the service once we reached the airport was very good

The airport temperature at the airport and on the flight was too warm

Boarding too way too long. Biggest peeve: zero in-seat power in economy! No plug sockets, no USB ports. Plane was an A330, so not old.

boarding is so disorganized, i was literally appalled at the boarding experience

Comfortable but not Polaris or Delta comfort Business Class. Overall 7 out of 10

Tap air Portugal was the best I will traveling again with u guys. Thank u.

The long wait at JFK made the trip horrible. Also not having enough buses when we deplaned was annoying

The food could be better, more snacks. And have some plugs to chargue the phone.

Everything was really great just The aircraft was too old and sounded it will break during takeoff

Extremely pleased with the crew. Best flight attendants ever! Very friendly, genuinely caring and attentive.

Best flight attendants ever! Very customer and service oriented, courteous, professional and helpful.

Cheapest airlines I have ever been on. I got downgraded and never got on united. I got rerouted through Vancouver onto jetwesf

Very small and uncomfortable seats, Hard to hear entertainment system sound. Horrible food. Staff doesn't care much about the passengers. 2nd time they didn't give me my vegetarian meal. They asked me regular food with meat. The airline and staff was from United airlines.

Checkin took along timen only.few angents available at.checkin desk. Customer support over phone no existence

At baggage claim, I was given the wrong printed ticket. The ticket belonged to another passenger for a different flight — to Zurich instead of Frankfurt (layover). I was even allowed to pass security, and when I asked the Lufthansa employee if I was on the correct flight, and why it was changed. The employee said everything was correct and I should board. When I got on the plane, there was someone in my seat, and the crew on the plane finally realized that I was on the wrong plane. When I got off the plane, nobody was willing to help, and the security refused to provide my original printed ticket. That was until I showed them that I took a photo of the ticket; once they realized I had photographic evidence, they were suddenly ready to help me. The Lufthansa employee began communicating with other airlines and found a flight that would take me to my destination via Polish Airlines. I was required to once again go through security, re-check my bag, and once again pay for my checked bag and weight overage fees. This experience was incredibly stressful and very frustrating, as you can imagine. A Lufthansa employee told me I would be eligible for a refund. Please tell me what steps I need to take in order to make that happen. Thank you!

Good service … bus transfer upon arrival from plane to terminal: atrocious!!!

helpful and friendly. The Lufthanza people I dealt with before my holiday were so unhelpful by comparison.

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