SFO - OPO

$341 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 5/18. 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, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights 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.
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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Everything you should know

Cheapest round-trip
$465
Overall average: $749
Scandinavian Airlines
Thu 3/12Wed 3/18
SFO - OPO • 1 stop
Cheapest one-way
$341
Typical prices: $495-$706
Multiple Airlines
Mon 5/18
SFO - OPO • 2 stops
When to book
3 weeks
in advance
Our data shows that travelers who book at least 3 weeks in advance save around 5% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
January
Cheapest • 29% price drop
July
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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Flight Deals
Booking Insights
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

Thu, Mar 12 - Wed, Mar 18
Scandinavian Airlines Logo
5:40 pm - 4:55 pmSFO-OPO
16h 15m1 stop
Scandinavian Airlines Logo
10:25 am - 3:35 pmOPO-SFO
36h 10m1 stop
$465Scandinavian Airlines
Find Deal
Wed, Mar 11 - Wed, Mar 18
Scandinavian Airlines Logo
1:05 pm - 4:55 pmSFO-OPO
44h 50m2 stops
Scandinavian Airlines Logo
10:25 am - 3:35 pmOPO-SFO
36h 10m1 stop
$475Scandinavian Airlines
Find Deal
Wed, Mar 11 - Wed, Mar 18
Scandinavian Airlines Logo
1:00 pm - 4:55 pmSFO-OPO
44h 55m2 stops
Scandinavian Airlines Logo
10:25 am - 3:35 pmOPO-SFO
36h 10m1 stop
$487Scandinavian Airlines
Find Deal
Sun, Mar 8 - Wed, Mar 18
Scandinavian Airlines Logo
5:40 pm - 4:45 pmSFO-OPO
16h 05m1 stop
Scandinavian Airlines Logo
10:25 am - 3:35 pmOPO-SFO
36h 10m1 stop
$488Scandinavian Airlines
Find Deal
Sun, Mar 8 - Fri, Mar 20
Scandinavian Airlines Logo
5:40 pm - 4:45 pmSFO-OPO
16h 05m1 stop
Scandinavian Airlines Logo
5:35 pm - 3:35 pmOPO-SFO
29h 00m1 stop
$498Scandinavian Airlines
Find Deal
Thu, Apr 16 - Fri, Apr 24
Scandinavian Airlines Logo
4:45 pm - 8:40 amSFO-OPO
31h 55m1 stop
Scandinavian Airlines Logo
5:55 pm - 2:40 pmOPO-SFO
28h 45m1 stop
$545Scandinavian Airlines
Find Deal
Mon, Feb 23 - Tue, Mar 3
Multiple Airlines Logo
4:35 pm - 9:15 pmSFO-OPO
20h 40m2 stops
Multiple Airlines Logo
9:55 pm - 2:30 pmOPO-SFO
24h 35m2 stops
$568Multiple Airlines
Find Deal
Tue, Mar 10 - Wed, Mar 18
British Airways Logo
6:30 pm - 5:35 pmSFO-OPO
16h 05m1 stop
British Airways Logo
6:30 pm - 7:45 pmOPO-SFO
32h 15m1 stop
$628British Airways
Find Deal
Thu, Jan 8 - Thu, Jan 15
Multiple Airlines Logo
8:25 am - 10:15 amSFO-OPO
17h 50m2 stops
Multiple Airlines Logo
6:35 am - 9:22 pmOPO-SFO
22h 47m2 stops
$632Multiple Airlines
Find Deal
Wed, Mar 11 - Wed, Mar 18
British Airways Logo
12:11 pm - 4:05 pmSFO-OPO
20h 54m2 stops
British Airways Logo
8:20 am - 10:27 pmOPO-SFO
21h 07m2 stops
$638British Airways
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 $652 (return) on average. On the other hand, the most expensive months are July and June, where the average cost of round-trip tickets is $1,223 and $1,170 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 5% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 13 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flight$341
Best time to beat the crowds with an average 30% drop in price.
Most popular time to fly with an average 33% 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 $341 for a one-way ticket and $475 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?

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

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

    Frankfurt am Main 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, Air Transat or SWISS?

    The two airlines most popular with KAYAK users for flights from San Francisco to Porto are Air Transat and SWISS. With an average price for the route of $819 and an overall rating of 7.8, Air Transat is the most popular choice. SWISS is also a great choice for the route, with an average price of $951 and an overall rating of 7.5.

  • 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.
7.5
SWISSOverall score based on 1794 reviews
6.8Entertainment
7.7Boarding
7.1Food
7.4Comfort
8.2Crew
Airline reviews

At boarding, the locations where we had to have our passports checked prior to boarding were very unclear. Occasional staff wandered around telling people, but in busy area of the terminal this was not obvious. It was also located well after the check in desk in terms of walking to the gate. The Premium Economy service was attentive and warm. The only big draw back was lack of restrooms, and no division or even curtain between PE and Economy.

8.0 ExcellentAnonymous, Oct 2025ZRH - MIA
Read more SWISS reviews

At boarding, the locations where we had to have our passports checked prior to boarding were very unclear. Occasional staff wandered around telling people, but in busy area of the terminal this was not obvious. It was also located well after the check in desk in terms of walking to the gate. The Premium Economy service was attentive and warm. The only big draw back was lack of restrooms, and no division or even curtain between PE and Economy.

Everything was fairly easy just hard when you get to Heathrow not know your Gate number until an hour before but otherwise really everything great. Did not get my texts in time though to do me any good but that is why I still like everything the old fashioned way and print everything out.

We flew an Air Bus 330 airliner from Zurich to Boston. Our seats were terrible. I am 6'5" with long legs. I tend to refuse paying extra for extra seat room, usually it's tolerable. We were side by side in row 40, with my wife in the window and me in the aisle. The internal arm rest only rose to 45 degrees, I thought it was broken. I ended up standing by our seats in the aisle for an hour. A stewardess finally approached me and asked if I was feeling sick. I told her that it was the worst seat comfort I had ever encountered. She left and shortly came back telling me that there were center row seats two up from us where only one passenger was sitting out of the 4 seats. I took her advice and sat there most of the flight. I put m legs sideways in the adjoining empty seat. But the arm rests there as well only rose to 45 degrees, so it's a feature, not a defect. The arm rest position really limits our position. It's a horrible seating design, what are the air craft designers thinking?

Food used to be better and comfort was not attainable after 5 hours everything starts hurting.

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.

This was an older airplane. The cabin was constantly warm to hot throughout the 10 hour flight and there were no vents to personalize air flow. Also since it was an older plane, the material and comfort of the chairs were very uncomfortable. I left my flight with major soreness on my tailbone.

Older aircraft, no meal, only food was for purchase. Not impressed United.

Not pleasant trip cross country when the entertainment and WiFi system not working. No entertainment for entirety of route. Staff was rather nonchalant in that they dismissed the problem due to age of plane. It would have been nice to know this up front so I could have come prepared to read or download movies before boarding Coincidentally or not, there was a similar issue with the entertainment system on my previous flight I took on my fist leg of the trip. There are no seat TVs, so you must rely on the app when it works. United can do better. Also, what use it it to pay for boarding group 2 when half of the passengers are in the same line as you?

My experience on this United Airlines flight was highly uncomfortable, primarily due to two issues: Cabin Temperature: The temperature on the Boeing 737 MAX 8 was unacceptably high, feeling consistently around 80 degrees throughout the flight. This made sleeping impossible and significantly detracted from the experience. Seating Arrangement: Being stuck in a middle seat for a six-and-a-half-hour overnight flight compounded the discomfort. Moving forward, I will always purchase a seat assignment to avoid this situation.

Premium Plus is a really good idea for longer flights

Same as last comment. Food sucks. Quality. Not surprising most people have no clue about nourishment Clearly

Food was poorly timed and not good.. Hand held snacks, really. I kept asking for water and never got any. Service was rushed for a 7-hour flight.

We were in business class. the angled seats in that class do not have a real window view & the placement of the controls are bad. But we knew that. But the food options were mediocre. The taste was fine, but the size was for a child. It’s just really feels like United is skimping on everything. Even when we were in the Polaris lounge they did not have diet sodas. They said they were out no Coke zero no Diet Coke, etc. I do not think the portion of nuts they serve on the plane could get any smaller. Really a minimal service and offer for what you’re paying for in business.

We had to deboard 2 times due to maintenance issues. They changed the plane, and then we got deviated to LAX due to maibtenance issues on the other plane, had to sleep at LAX and los a full day.

From the first moment you interact with United Airlines, you can expect nothing less but extreme frustration. The baggage handler at the bag drop seems completely unbothered by the presence of customers waiting in line. No help was extended to load the baggage whatsoever. And if any of your bags is overweight by 0.01 pound they will make you re-distribute everything in your suitcase just to play power trip. When it was time to board no help was extended to customers to locate their seats. Moreover. It was a chaotic mess at the gate when it was unclear who should board first and everyone just bunched up, trying to get on the plane. I am sure the crew was doing their best to perform their jobs while being paid their wages however it shouldn’t be that hard to smile once or twice when you’re in the business if serving customers. It is a shame for the United States of America to have a flagship carrier of such low caliber. Our flight was also delayed by about an hour and a half due to further delays prior to our inbound flight. Being someone who has travelled for both business and leisure in Asia, Europe, and South America I have never experienced such poor quality of service.

Great check in process in LA and good service The check in process as well as at the gate is way better in the US versus canada 🇨🇦

All attendents were very efficient, pleasant and happy. Everything went smoothly. The seats could have been wider. There could have been more free food instead of just one small bar.

I liked a lot , the flight attendant so nice ,the seat very comfortable I enjoyed the flight , I will do it again with Air Canada,

It was a smooth flight both in the sky and landing!

The crew was really nice. The plane seats were kinda small even for a 5’6” / 158 lbs person.

Fare was great, seat comfort the opposite as cushion was worn out. Ok for 2 hour flight, not for 4.5 hour flight..

Fair. What's the point of partnering with United if we cannot use the lounge. My wife is a frequent flier with United but we were refused access to Air Canada lounge

Real smooth and easy, Real good leg room in coach!

Re luggage I carried a backpack only. I did not check any bags in. However there were other passengers with carry on luggage going in the plane. My question is why are others allowed to have a carry on luggage inside the plane? Shouldn’t they have dropped it off at the gate? I’m asking because I could have brought the same thing instead of a backpack only. Please clarify for future reference. Thank you.

Like the service. Very hard to communicate or contact when have problems

Wonderful just hope the had more direct flights to Boston

Boarding process was fast and efficient. Short flight but on time and well organized. I would certainly fly TAP again.

Very borderline, low budget airline without low budget prices There are no counts of soda, everything is dispensed enlarged bottles and poured into tiny cups about 70 mL so in order to keep hydrated you have to take 3-4 cups at a time. Also, there was only one food item offered, pasta, they ran out of chicken right away. Snack was very poor. It was called tuna sandwich, which is truly borderline. The flight attend attendance seemed to be overworked and tired.

TAP‘s flight attendants seem to be among the least ambitious of all the international flight crews we’ve flown with. . When we left US and went to Portugal, and when we returned from Portugal, flight attendants were not very visible. Then did not offer frequent water breaks and when we had to go back to request water, I was almost an imposition. Meal quality was just average. The dinners were fine. Breakfast wraps were presented soggy.

Did not enjoy the meal provided. The aircraft was dirty. For instance, the screen seemed to have been cleaned with a dirty rag. Disgusting.

The business class seats were smaller and closer together than other airlines.

Boarding- Good Seat Comfort - OK Crew - Good Food - Mediocre On Time - Very Good

Didn't like much. Wheelchair assistance was almost nonexistent. No one at TAP check in process helpful. On the plane, stewards were not friendly and disorganized. Food was terrible for 8 hr flight. We were skipped at snack time and even though we tried to get attention using overhead call system no one even looked up at us to acknowledge. Being at the back of first section and by the lavatory we only were able to request when they came to pick up everyone else's garbage and they were nonchalant...no apology or even choice. The 1/2 half bread with slice of cheese was a waste. Deplaning was horrible but I'll blame lisbon airport for that. Plane left late at made good time still arrived about 15 behind schedule and for using remote deplaning and bus to terminal took another 20 min to gate. Those with connections were highly stressed. Took us 2 hrs from landing to get to ground transportation and exit airport. And that was with wheelchair assistance.

Bad boarding, threat to force bag check mid journey, lines, late, buses, more waiting awful end to end.

Check in was excellent thanks to the team at the check in counter. I was disappointed to see that one has to pay for coffee on the flight. This is the first time I have seen that after 60 years of flying.

Lufthansa still has a good level of quality compared to US airlines, especially with respect to (1) food quality - actually tasty, (2) good French red wine - free, (3) good movie selection. Also my ticket price includes 1 free check-in luggage, while some other budget airlines sneak in an extra $150 for a checkin.

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!!!

Everything you need to know for your flight from San Francisco to Porto

Information on your arrival and departure airports