$154 Find Cheap Flights from San Francisco to Portsmouth - Compare and Save

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 9/15. 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, 0 bags

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Everything you should know

Cheapest round-trip
$297
Typical prices: $324-$554
Alaska Airlines
Tue 8/11Wed 8/19
SFO - BOS • 1 stop
Cheapest non-stop
$297
Typical prices: $277-$479
United Airlines
Sat 9/12Sat 9/19
SFO - BOS • Non-stop
Arrival airport
You can't fly directly to Portsmouth. It is served by Boston (BOS), located 50.3 miles from Portsmouth.
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Flight Deals
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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

Tue, Aug 11 - Wed, Aug 19
Alaska Airlines Logo
7:55 am - 5:40 am
SFO
-
BOS
18h 45m
1 stop
Alaska Airlines Logo
8:00 am - 2:45 pm
BOS
-
SFO
9h 45m
1 stop
$297Alaska Airlines
Tue, Sep 1 - Fri, Sep 11
JetBlue Logo
3:19 pm - 12:35 am
SFO
-
BOS
6h 16mnonstop
JetBlue Logo
5:15 am - 10:39 am
BOS
-
SFO
8h 24m
1 stop
$298JetBlue
Sat, Sep 5 - Tue, Sep 15
JetBlue Logo
3:19 pm - 12:35 am
SFO
-
BOS
6h 16mnonstop
JetBlue Logo
5:15 am - 10:39 am
BOS
-
SFO
8h 24m
1 stop
$299JetBlue
Tue, Sep 22 - Mon, Sep 28
JetBlue Logo
8:25 pm - 7:57 am
SFO
-
BOS
8h 32m
1 stop
JetBlue Logo
9:35 pm - 1:03 am
BOS
-
SFO
6h 28mnonstop
$300JetBlue
Mon, Aug 24 - Tue, Aug 25
Alaska Airlines Logo
5:16 pm - 5:49 am
SFO
-
BOS
9h 33m
1 stop
Alaska Airlines Logo
8:00 am - 3:59 pm
BOS
-
SFO
10h 59m
1 stop
$301Alaska Airlines
Sun, Aug 23 - Wed, Aug 26
Multiple Airlines Logo
10:35 pm - 11:47 am
SFO
-
BOS
10h 12m
1 stop
Multiple Airlines Logo
8:00 am - 2:45 pm
BOS
-
SFO
9h 45m
1 stop
$302Multiple Airlines
Thu, Aug 27 - Tue, Sep 1
Multiple Airlines Logo
10:35 pm - 11:47 am
SFO
-
BOS
10h 12m
1 stop
Multiple Airlines Logo
5:20 pm - 8:56 pm
BOS
-
SFO
6h 36mnonstop
$303Multiple Airlines
Tue, Sep 8 - Tue, Sep 15
JetBlue Logo
6:00 am - 2:41 pm
SFO
-
BOS
5h 41mnonstop
JetBlue Logo
6:55 am - 10:30 am
BOS
-
SFO
6h 35mnonstop
$304JetBlue
Fri, Aug 28 - Wed, Sep 2
JetBlue Logo
9:44 pm - 6:28 am
SFO
-
BOS
5h 44mnonstop
JetBlue Logo
12:57 pm - 10:11 pm
BOS
-
SFO
12h 14m
1 stop
$305JetBlue
Mon, Aug 17 - Sat, Aug 22
Multiple Airlines Logo
11:05 pm - 11:47 am
SFO
-
BOS
9h 42m
1 stop
Multiple Airlines Logo
8:00 am - 2:45 pm
BOS
-
SFO
9h 45m
1 stop
$306Multiple Airlines
Useful Info

Good to know

Low season

January

Cheapest flight

$154
Best time to beat the crowds with an average 21% drop in price.
Most popular time to fly with an average 19% 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 35m.

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

    52 direct flights run between San Francisco and Portsmouth on a daily basis. On average, there are about 368 departures each week.

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

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

  • 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 5 days, the cheapest one-way ticket between San Francisco and Portsmouth found on KAYAK was with Frontier for $97. Frontier offered a round-trip connection from $106 and Hawaiian Airlines from $118.

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 72 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 May, June and July. The cheapest month to fly is January.

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.
7.9
Alaska AirlinesOverall score based on 12671 reviews
7.0Entertainment
7.8Comfort
8.5Crew
7.0Food
8.1Boarding
Airline reviews

The app booked me on a flight for July 1st as opposed to August 1st like it was supposed to be. No problem with Alaska Airlines, except they took a while to refund my money. But it was as taken instantly. So, yeah.

2.0 MediocreAnonymous, Jul 2026
SFO - LAX
Read more Alaska Airlines reviews

The app booked me on a flight for July 1st as opposed to August 1st like it was supposed to be. No problem with Alaska Airlines, except they took a while to refund my money. But it was as taken instantly. So, yeah.

Not able to get boarding pass for domestic connection flight when check in at international airport. I was told I need to get connection flight boarding pass after I entered US. It us very inconvenient.

They called me 2 hours before my original flight from SFO was to depart to let me know it was delayed and that I would miss my connection. They then rebooked on a different flight leaving a half hour earlier to a different connecting airport, so that I would not miss my connection. It all worked out and I arrived at my destination without a problem and 15 minutes earlier than the original flight would have. Nice!

The flight would have been very good , if not dor the constantly screaming baby in the row behind me. Is there a way to isolate people traveling with infants? This is not the first time this has happened to me.

They treat me well because of my one world status. Crew is attentive and professional. One of the best airlines out there.

Crew were bad Didn’t help with luggage When asked for a glass of wine, I was told that they will serve later , which they didn’t to Me and didn’t serve anyone else in First class . Didn’t offer any snacks , Chips or Nuts to anyone . Flight was not crowded either. Worst Service/ or No Service !

Alaska drastically changed our flight from a direct flight to a flight with connection and a long layover. So we canceled the Alaska flight and we learned a valuable lesson that we will never book through kayak again because the third party travel agent tried to withhold our money.

Four hour delay. Missed our event. And they offered me $75. Absolutely shameful.

I have been flying commercial for decades. I was in one of the ladder boarding groups, had my bag tagged because they thought there was not going to be enough space for it in the overhead bins. I politely asked one of the attendance if I could try to find a space- she said I could and I did. I then took the bag tag off and gave it to one of the other attendants as I was told to do by the first one. He, in a curt, anal, and disrespectful manner, told me that I needed to take my bag down from the overhead bin and check it. This was a situation I’ve never encountered before. The attendant’s attitude was confrontational and belittling in front of other onlooking passengers as if daring me to challenge him. I am a physician who takes care of patients day in and day out. Not wanting to make a scene, I calmly told him, “do what you need to do.” he took my bag down from the overhead bin, put the back tag back on it, and checked it only to make room for another bag that was also supposed to be technically checked by a following passenger. The same male attendant later came up to me and said “you shouldn’t have showed me the bag tag,” as if conveying that he was just following protocol was a justification for treating me like a kid out of line. I cared about this because it took 15 minutes from my life to then retrieve the bag at baggage claim and it also felt like really poor customer service. I understand the need for protocols. This is also a service industry, and we the passengers are the clients. We should be made to feel welcome and respected and our life in transit made as easy as it can be within reason. This attendant clearly needs to be reminded of that. Of note, an older female fellow passenger sitting next to me agreed with this assessment.

Nice crew, healthy snacks and drinks available. Flight to Seattle was short and comfortable.

Crew was absolutely fantastic and we’re so welcoming and friendly ❤️

Flight delayed four separate times. I’m now one hour hours late to landing.

The plane was an older model, so it wasn’t as comfortable as others. The flight attendants were not helpful during onboarding. It was a full flight so there was chaos finding space for baggage.

Awesome! On time flight, early arrival, and a complimentary upgrade!

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

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

Excellent flight, the planes were newer, they did a nice job with boarding, great service overall.

Thank you for not flipping the plane on the run way. You guys get a 5 star rating for the flight!!!

Boarding is, as it always is… horrible. Gate lice. Slow moving zones. Too many people with carry ons

New boarding doesn't make sense. Filling front first is slow.

It was a short, comfortable flight. It did leave an hour late due to the pilot having to be replaced (family emergency) but that didn’t inconvenience myself & my friend. The situation was explained, eventually.

Lost one piece of luggage even though I checked in 2.5 hours before the flight

Horrifying Almost 2 million miles. Bring your own food and drink. One coffee or drink every three hours. Have to order meals on app more than 24 hours ahead Tiny and dirty bathrooms

My service dog and I were asked to deplane just before they closed the door - clearly very last minute they couldn’t find the documentation that I have filled out many many times before that is for flying service animals. I purposely purchase 3seats (a whole row) since he is large and not all passengers want to sit next to a dog on a cross country flight. The plane departed with my husband on it!!! They made me fill out a hard copy of the same form and had to reschedule me on a later flight where they could find 3 seats together!! I’ve done this so many times before - clearly the error was on their part in a technology glitch - but really people - do better!! Very traumatic - and my husband had to wait for us when he landed ….so bad. Poor pup was confused and tired.

No screens or meal options. Freezing cold. Dirty seats. Left late.

Outstanding service, efficient & friendly crew, flight was safe, comfortable & on time

It was a red-eye, but the flight felt surprisingly quick. The seats were very comfortable, and that made resting much easier. I also want to thank the gentleman seated next to me, who graciously moved so my mom could sit beside me. We slept almost the entire way. The cabin crew was respectful in not disturbing us, while also being courteous and professional throughout. Thank you, United.

Boarding was again a "free for all". We were boarding group 4, and almost the entire plane was able to board before us. It's a shame that someone who follows the rules, gets the short end of the stick. Not fair.

It was perfect! I've never flown with United before, but I definitely will in the future

They delayed the flight from 9:00 to 11:55 At 11:45 they canceled the flight. I paid a premium price for the tickets with poor service

Aside from the little delay, overall was flight good. Made it safely. Thanks!

Over the course of 7 months of travel, I can count on my hand the number of times the flight has departed on time. Majority of the instances have been related to non-weather reasons. Would not recommend flying this Airline

The plane was spartan, the seats not that comfortable. It was like flying a super low budget airline. They charged for coffee!!! I have never, ever experienced that before.

I had no problems but the changing of planes that I was supposed to be on was confusing. Maybe it would be helpful to let people know your flight changed. Not everyone understands airports or how flying works.

Flight was delayed multiple times without giving any particular reason and the only thing that was communicated was that 'Aircraft is getting ready'. I was stuck at SFO airport for 15 hours and finally took Southwest Airlines flight back home to Dallas.

I was not clear if food was offered or not.

Agency very bad had to cancelled my booking too many changes in the flight changed my flight to 1 week

Take-off delayed an hour because of a missing flight officer, so,arrived in Charlotte lates causing many passengers to miss connections. Otherwise a very good flight, safe and comfortable, with an excellent professional crew.

The SFO Lounge crew were amazing. The bartender Faris was great. Thanks!

Not good. One of my luggage is missing. And until now they can’t find it

Seats were great, the staff was great, and the food was about the best I've had on a plane, and is especially the best of any US-based carrier I've flown. Free Wi-Fi was also great.

It was inexplicably canceled and we are stuck in LA, haven't gotten home and it has been an inconvenience having lost work (on unpaid leave for my husband).

It was good. I’m very disappointed that they don’t give commentary ear pods for the movie. I forgot mine at home

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.

Too many long delays with JetBlue. Worst major airline that serves JFK but unfortunately I keep going back because of the prices.

Little snafu at boarding. Staff communicated with gate poorly. Flight attendant was rude making disembark early. This was an older mint class. Needs an overhaul for sure. Food was good. The male flight attendant was really nice.

I really liked the way snacks and drinks were available throughout the flight!!! The flight attendants were also all fantastic!

Always like Jet Blue! It seems, however, that people are getting bigger & seats are getting smaller! We had a very full flight and I couldn't get an aisle seat like I always do. I wish there were more leg room. People sitting next to me were very nice though so it was fine to disturb them if I needed to use the restroom. Otherwise the flight was fine but a bit long.

None of the in flight Direct TV worked. A better selection of Shows would have been better. The baggage was s low. Otherwise we enjoyed our flight!

the staff was very helpful and the airline was very good.

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

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