$124 Find Cheap Flights from San Francisco to Portsmouth

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 Portsmouth departing on 3/25. 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

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Everything you should know

Cheapest round-trip
$219
Overall average: $347
Frontier
Mon 3/16Wed 3/18
SFO - BOS • 1 stop
Cheapest non-stop
$223
Typical prices: $258-$494
JetBlue
Wed 3/4Wed 3/11
SFO - BOS • Non-stop
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Flight Deals
Useful Info
Flight Deals

Cheap Flights from San Francisco to Portsmouth (SFO-BOS)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from San Francisco to Portsmouth 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 Portsmouth

Mon, Mar 16 - Wed, Mar 18
Frontier Logo
10:38 pm - 11:41 am
SFO
-
BOS
10h 03m
1 stop
Frontier Logo
11:51 am - 7:14 pm
BOS
-
SFO
10h 23m
1 stop
$219Frontier
Tue, Mar 10 - Tue, Mar 17
Multiple Airlines Logo
10:40 pm - 10:29 am
SFO
-
BOS
8h 49m
1 stop
Multiple Airlines Logo
8:59 pm - 12:51 am
BOS
-
SFO
6h 52mnonstop
$220Multiple Airlines
Sat, Apr 18 - Tue, Apr 21
Frontier Logo
10:38 pm - 11:45 am
SFO
-
BOS
10h 07m
1 stop
Frontier Logo
6:00 am - 4:54 pm
BOS
-
SFO
13h 54m
1 stop
$221Frontier
Wed, Mar 4 - Wed, Mar 11
JetBlue Logo
3:25 pm - 11:58 pm
SFO
-
BOS
5h 33mnonstop
JetBlue Logo
8:40 pm - 12:31 am
BOS
-
SFO
6h 51mnonstop
$223JetBlue
Tue, Mar 10 - Tue, Mar 17
JetBlue Logo
12:30 pm - 9:08 pm
SFO
-
BOS
5h 38mnonstop
JetBlue Logo
6:09 pm - 9:59 pm
BOS
-
SFO
6h 50mnonstop
$224JetBlue
Sat, Apr 18 - Sat, May 2
Multiple Airlines Logo
10:38 pm - 11:45 am
SFO
-
BOS
10h 07m
1 stop
Multiple Airlines Logo
9:10 pm - 12:54 am
BOS
-
SFO
6h 44mnonstop
$225Multiple Airlines
Tue, Mar 10 - Tue, Mar 17
JetBlue Logo
8:44 pm - 5:15 am
SFO
-
BOS
5h 31mnonstop
JetBlue Logo
8:59 pm - 12:51 am
BOS
-
SFO
6h 52mnonstop
$226JetBlue
Tue, Mar 3 - Wed, Mar 4
Alaska Airlines Logo
11:34 am - 11:59 pm
SFO
-
BOS
9h 25m
1 stop
Alaska Airlines Logo
7:00 am - 2:02 pm
BOS
-
SFO
10h 02m
1 stop
$227Alaska Airlines
Wed, Mar 4 - Wed, May 20
JetBlue Logo
12:30 pm - 9:08 pm
SFO
-
BOS
5h 38mnonstop
JetBlue Logo
9:10 pm - 12:54 am
BOS
-
SFO
6h 44mnonstop
$228JetBlue
Mon, Mar 9 - Tue, Mar 17
Multiple Airlines Logo
10:38 pm - 11:41 am
SFO
-
BOS
10h 03m
1 stop
Multiple Airlines Logo
6:09 pm - 9:59 pm
BOS
-
SFO
6h 50mnonstop
$229Multiple Airlines
Useful Info

Good to know

Low seasonJanuary
Cheapest flight$124
Best time to beat the crowds with an average 12% drop in price.
Most popular time to fly with an average 10% increase in price.
Flight from San Francisco to Boston

When to book flights from San Francisco to Portsmouth

Are your dates flexible? Find out the best times to travel from San Francisco to Portsmouth based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price

FAQs for booking flights from San Francisco to Portsmouth

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

    When flying out of San Francisco you’ll be using San Francisco. Portsmouth does not have its own airport so you’ll be flying into nearby Boston Logan Intl airport, which is 50.3 mi away.

  • How long does a flight from San Francisco to Portsmouth take?

    Direct flights cover the 2,696 miles separating San Francisco and Portsmouth in about 5h 31m.

  • How many flights are there between San Francisco and Portsmouth?

    39 direct flights run between San Francisco and Portsmouth on a daily basis. On average, there are about 273 departures each week.

  • What’s the cheapest day of the week to fly between San Francisco and Portsmouth?

    Consider leaving on a Tuesday and avoid Saturdays if you are looking for the best rates. For your return to San Francisco, you’ll find the best rates on Wednesdays and the most expensive ones on Sundays.

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

    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 Portsmouth.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Portsmouth 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 Portsmouth?

    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 Portsmouth with an airline and back to San Francisco with another airline.

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

    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 Portsmouth from San Francisco up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • Which airlines provide the cheapest flights from San Francisco to Portsmouth?

    In the last 72 hours, the cheapest one-way ticket between San Francisco and Portsmouth found on KAYAK was with Frontier for $85. Frontier offered a round-trip connection from $91 and Hawaiian Airlines from $129.

Top tips for finding cheap flights from San Francisco to Portsmouth

  • There is no airport in Portsmouth. Instead, you’ll be flying into Boston Logan Airport when flying between San Francisco and Portsmouth.
  • The cheapest flight from San Francisco to Portsmouth was found 69 days before departure, on average.
  • Book at least 2 weeks before departure in order to get a below-average price.
  • High season is considered to be November, December and January. The cheapest month to fly is February.

Reviews of the top 5 airlines serving San Francisco to Portsmouth

 
Need help choosing which airline to fly with from San Francisco to Portsmouth? 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.
8.0
Alaska AirlinesOverall score based on 11850 reviews
8.5Crew
8.1Boarding
7.1Food
7.8Comfort
7.0Entertainment
Airline reviews

The he whole flight was very smooth on every aspects.

10.0 ExcellentPhilip, Feb 2026
SFO - SAN
Read more Alaska Airlines reviews

The he whole flight was very smooth on every aspects.

I paid for wifi and it never worked... it was miserable. I couldn't access my shared files to work on the plane, it didn't work on my phone. I paid for nothing but frustration and continual refreshing, hoping it would work

The stewardess are very nice and pleasant, Someone onboard had a medical attention, and they attended that person non-stop all throughout the flight, and yet, did not forget to serve and help other passengers.

The Alaska Airlines app made it very difficult to find my boarding pass. It was very frustrating to use! The flight itself was flawless.

The flight was excellent and very friendly and helpful staff. Will travel again and recommend to friends. Thank you

Did not have In flight service on my round trip due to turbulence. I did not partake in In flight entertainment. Flight descending into LAX was very turbulent. It would have been nice if the pilot communicated with us during that rough descent into LAX to ease the minds of some of us more nervous flyers.

They canceled my flight with only a couple hours before checking in at the airport and offered no alternatives to get home.

I had entered my TSA pre number when I bought the ticket but TSA pre was not on my boarding pass. I went to find an agent at check in and there was only one agent one duty for first class and a line of people waiting for check in/baggage with no agent manning that area.

Comfort level was below par. Food selection was non-existent. Paying $35 for 1st bag is never appreciated. I will not fly them again. I am actually trying to change my return flight.

The flight attendants were excellent and I was in the back of the plane. Much much better than recent JetBlue experiences on that route and better than Delta on that route.

Delta One is extraordinary. I fly business when somebody hires me. I just wonder why there is such a chasm between business class and the insanely inhumane and nonsensical coach. The seats are not large enough to fit even my tiny wife. We fly 10% of what we did because we don’t want to pay 5-10 k but for $400 it’s unbearable. It seems like the accountants took over and made stupid decisions. Screw in 20 extra seats and make it so unbearable that people fly 90% less. Just put the damn price up and put some proper chairs in. But business, yay.

Delta’s staff is unmatched. From the gate agents, to the pilots, to the flight attendants… all top of the industry.

The flight was delayed for about 2 hrs. Other than it, it was good.

I am extremely disappointed that delta internal pilot manuals now refer to the Gulf of Mexico as the “gulf of America”. You can bow down to the Orange turd on your own. I will never fly delta again

No lunch on a x-country flight scheduled for 10:50 am departure, arrived 5+ hrs later. That requires a black box label before you pay for the tickets. Worst, when I checked in online, it's specifically said that lunch was served on his flight for economy Plus passengers.

Our flight from SFO to MSP was right on time on 11/15/2025. No delays. As we approached MSP at about 8 pm, we circled in the air until 8:40 pm so I don't call that efficient for MSP. I think the captain should announce the delay and why. (as if we all don't know that we are just circling around the area, slowing down, speeding up, slowing down.) Thank you. Marilyn Fischer

Staff were friendly and happy. Delta could make sure passengers that don't have the app know of changes. Without Kayak I would not have known about the change of gate or the delay. Kayak was faster to notify me.

The flight used a B767 with a very old interior from before 2014. The entertainment system did not work at all during the flight despite attempts to reset the system. It was like they flew this route just to be competitive.

Delayed flight (1hour) plus a long layover after an overnight flight with no backup plane available.

Flight delayed for two and half hours and then canceled altogether due to mechanical issues. No mechanic onsite to fix so had to send one from LAX.

I like that if they asked you to checked in a bag at the gate they give you priority to board

I received several emails about my 3:10 flight. When I showed up to the airport at 12:30 to check my bags I was told the flight was actually at 1 pm. They grudgingly rebooked me for a flight at 5:22 to Vegas to get a connecting to LAX. I did find the gate for my original 3:10 flight but they were booked. I proceeded to receive status updates and gate change information for the 3:10 flight, even though I was apparently never supposed to be on that flight

The food options were limited and very specific. Some type of entertainment option for a 4.5 hour flight would have been nice.

The Kayak confirmation number did not work for checking in the day before. I checked in at 8.30 using my ticket number. When I arrived at the airport, I was informed that the flight was overbooked, and since I had checked in late, I did not have a seat. The Next flight was not until ten PM. I called my wife, who had been taking care of our kids all weekend, and she was upset, calling me a liar and telling me to stay in SD. It turned my weekend getaway into a nightmare! I blame the Kayak website and will not book flights using your app in the future.

comfortable but the food is horrible. I have flown Hawaiian several times now and no matter what they say the food is its the same squashed bread with melted goop inside. Tastes fake and isnt what they represent, its quite nasty. What happend to real food? And there is NO entertainment!! so not sure why they are asking for a review on that.

Good and friendly staff. Nicely enjoyed the complimentary drink and snack.

I was very, very cold and a stranger loaned me her sweater next to me. I didn’t wanna buy a blanket just for a four hour trip when I did not need the pillow or the earphones. I don’t mind purchasing a blanket, but I only needed that not all of it accessories. Cold air pretty much blew the entire trip. Two people in front of me both bought the blanket packages. Maybe that’s the idea. The crew was exceptionally nice and passed through multiple times.. the restrooms were very clean and usually accessible.

3 hour wait on customer service after flight was cancelled. Was bumped to a flight where I wouldnt have gotten to my destination for another 2 days. Had to fully refund flight and book a new one the following morning. Paid twice the amount for the flight than I had originally booked. Very disappointed I was not offered any sort of discount or points for all of the frustration, in fact the airline profited twice as much off of me by cancelling my flight and and changing my entire trip.

I understand that both Hawaiian and Alaskan are in the process of merging but I could not get real-time flight info or access my boarding pass on either app

Had a hard time checking into my flight on my phone because they gave me the wrong confirmation number. Otherwise everything else went well.

The flight crew where really good. Better then the crew from BNE to SFO

Food should be changed in menu Many muslims travels in this airlime they need to add one Halal meal

left on time, reasonable boarding process arrived early luggage came out quickly

Some flight attendants were great others were cranky. Seats were very tight and sitting on an aisle was very hard as the carts and people walking constantly bumped shoulder and arm.

Pushed back only to get deplaned due to a tire damaged by ground crew. They did at least go pretty fast. The bathrooms should be banned under the Geneva convention. No room to even sit straight on the toilet. The under-seat entertainment units block what little leg room there is.

United airlines has the best customer experience from booking to arrival. I always fly United airlines. The mileage program is excellent

from SFO-> FRA flight, AVML meal was significantly less compared to regular meal, especially no Desert, no Bread, no sides.

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?

Premium Plus is a really good idea for longer flights

The crew for the flight was A+ top notch. They were friendly and professional and made the flight a very relaxing and enjoable.

Rude crew member. She seemed annoyed at me without me saying a single word. Also loudly admonished me for having my bag next to my seat instead of tucked away before landing. Just telling me to put it away and guiding me without giving me a lecture would have been enough.

No included food for a 5 hour flight and the entertainment was only accessible if you had wired headphones (not provided). Otherwise though, great and smooth flying and customer service.

Crew were fantastic and so catering and wonderful! Full score for the entire crew!

Because of weather and mechanical issues our flight was 4 hours late. The only compensation offered to us was a meal voucher to be used only at Boston Airport and only on the day issued. But by the time it was offered to us all the restaurants were closed, so there was no way to use that offer.

Friendly crew, efficient boarding and flight arrived early. Couldn’t ask for a better experience

Terrible. They canceled our early morning flight after midnight on the day of and had no available flights to rebook my family on for the next 72 hours. Yet they still had other flights that were not cancelled from JFK so it couldn’t be based on the weather. It felt like they canceled the flight based on it not being profitable enough for them. I am not interested in traveling with the again. The absolute worse customer service and lack of accountability.

Horribly rude check in at airport, worst in 25 years of flying. All over a simple issue they could have googled to resolve.

First time flying with JetBlue and never again. I went to the counter to request meet and assist because I'm 74 and my wife is 79. I walk with a cane and my wife is handicapped and has her own wheel chair. I told the agent that my wife and luggage was at the entrance door. The ticketing agent said to me that they don't offer meet and assist. I need to bring them our luggage and then go back and get my wife in order to get my boarding pass. As I went back to get my luggage a Southwest agent along with a TSA agent recognized the situation and came over and took my wife and luggage to the JetBlue ticketing counter alongside the line and told the JetBlue agent to issue to take our luggage as soon as they could.

1) No pilot available for 1 hour 2) no room for most passengers careyon in overhead—-> stowed below 3) when we landed we had to wait 45 min. Before docking at gate as gate was not ready

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

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