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Find cheap flights from Seattle to Portsmouth from $139

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Seattle to Portsmouth departing on 5/29. 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
0 bags
Fri 6/7
Fri 6/14

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Good to know

Low season

January

High season

August

Cheapest flight

$139
Best time to beat the crowds with an average 40% drop in price.
Most popular time to fly with an average 19% increase in price.
Flight from Seattle to Boston

When to book flights from Seattle to Portsmouth

Are your dates flexible? Find out the best times to travel from Seattle 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 Seattle to Portsmouth

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

    When flying out of Seattle you’ll be using Seattle/Tacoma Intl. 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 Seattle to Portsmouth take?

    Direct flights cover the 2,487 miles separating Seattle and Portsmouth in about 5h 24m.

  • How many flights are there between Seattle and Portsmouth?

    40 direct flights run between Seattle and Portsmouth on a daily basis. On average, there are about 286 departures each week.

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

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

  • How does KAYAK find such low prices on flights from Seattle 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 Seattle to Portsmouth.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Portsmouth from Seattle 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 Seattle 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 Seattle with another airline.

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

    In the last 72 hours, the cheapest one-way ticket between Seattle and Portsmouth found on KAYAK was with Spirit Airlines for $139. Spirit Airlines offered a round-trip connection from $188 and American Airlines from $261.

See more FAQs

Top tips for finding cheap flights from Seattle to Portsmouth

  • There is no airport in Portsmouth. Instead, you’ll be flying into Boston Logan Airport when flying between Seattle and Portsmouth.
  • The cheapest flight from Seattle to Portsmouth was found 41 days before departure, on average.
  • Book at least 1 week before departure in order to get a below-average price.
  • High season is considered to be June, July and August. The cheapest month to fly is January.
See more tips

Top 5 airlines serving Seattle to Portsmouth

 
Need help choosing which airline to fly with from Seattle 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 9147 reviews
7.3Entertainment
7.3Food
7.9Comfort
8.6Crew
8.2Boarding
Airline reviews

The flight was decent again if there was a place that you could put crying children that would be great. Or maybe make a rule against allowing infants on the plane.

6.0 GoodAnonymous, May 2024SEA - HNL
Read more about Alaska Airlines reviews

The flight was decent again if there was a place that you could put crying children that would be great. Or maybe make a rule against allowing infants on the plane.

Everything was fine -- on time, clear, clean. I don't want to pay extra for in-flight wi-fi

The flight was delayed because the pilots had not arrived on their previous flight yet. The flight was 100% full so it was pretty crowded. I miss having the screens on the back of the seats. It would be great if the Alaska planes had the clip so you can put your phone or tablet on the back of the seat in front of you to not strain your neck. Everything else was very smooth.

It was fine since it ensure we went to our destination in time.

I bought the cheapest ticket. No meal, no checked luggage so I didn't expect much and was surprised by how good the flight and service was. Alaska is now my favorite airline.

No entertainment, food was cookies & juice,water, soda or coffee.

My baggage was in another flight, anit was delayed for one hour.

The maintenance delay was seemingly handled very poorly... Little to no information was provided to the passengers sitting on board for an extended period of time. On a brighter note, at least the cabin crew (flight attendants) did the best they could. They seemingly were provided very little information with regards to the delay. Unless absolutely beyond my control, I can’t imagine buying a ticket on Alaska airlines again, based on this and a previous experience my wife recently had, along with complaints overheard from other passengers.

The only issue was in the wheelchair waiting area before we got on the plane. They seemed very disorganized. Everyone we encountered after that was great! We loved Cassandra at check-in. She was awesome. The flight attendants were wonderful too! The lady helping with the waiting wheelchair when we got off the plane was awesome too!

Expect to get miles for us having to miss our first planned flight due to them waiting on passengers that decided to be late to the airport.

Had a broken tray in business class. Crew just shrugged it off.

Everything was great except for the seat. The backrest would not stay in the upright position.

public website still broken for years randomly blocking browsers with privacy options active after loading a page maybe once. check-in on laptop was almost impossible but eventually randomly worked. had to print pass at airport since couldn't get back in to load digital pass on mobile firefox or chrome. red eye flight so smooth onboarding, plenty of room to spread out, easy offboarding. onboard wifi instructions mention vpn can cause problems connecting but fails to also mention private dns. no printed or built in menu list, seems weird to require personal device to point at qr code link for menu which does not even allow direct ordering. people with health condition risk related dietary restrictions trying to avoid for example cholesterol and sugar are left guessing what they can order either way without nutritional info highlights (cranberry juice was minute maid cocktail with as much suger as typical can of soda). tap to pay wasn't working and always seems sketchy to manually enter card info. good movie variety, so limited tv was okay.

Bag drop off was slow and annoying. Only 2 agents at the entire delta desk, and no one directing traffic for what line to be in, many confused people slowed down the process. Boarding was fine. Seats in Delta comfort plus were fine. Snacks were great! Definitely a bonus. The entertainment system was awful — old, slow, not responsive, and completely unable to play games due to some kind of error. But on the other hand, thank you to Delta for the free WiFi. That made it better.

Flight diverted in SD. Later take off in Seattle by 1.3hrs

Mi primera conexión se retrasó por lo cual perdí mi segunda conexión la cual salió adelantada

Crew was not friendly when I went to request a seat change.

There were choices for the snacks. Good choices and tasty lunch and breakfast as well.

The flight crew was amazing. I’m very tall and they moved me to an exit row unsolicited!!! Amazing service.

The boarding process was terrible especially with an indirect flight Chicago to Seattle to San Diego was terrible talking about we overbooked a flight idk if I’d take this airline ever again we got off our flight from Chicago to Seattle and we traveled for business and they told us our connecting flight was over booked and their was no seats asking people to take a delayed next flight and they don’t tell anyone coughing to wear masks seats 30A-B were terrible during the flight no one wants to sit next to people coughing all around I don’t want to be sick traveling for work or get sick anytime it’s very upsetting the staff doesn’t take this stuff serious to tell them to wear masks when they see people coughing and sneezing

Great. Loved that there was WiFi on flight to keep in touch and excellent service of beverages and snacks.

Business class is great. New airplane, very comfortable, better than some of the major airlines I am used to

Terrible. Flight was cancelled due to the weather in the east and sout east(florida). Did not get any compesation of any kind. According to them, it was not under their control so I lost all the money paid for the 2 fairs from Raleigh, NC to Orlando, Fl.

great flight. Pilot was communicative, flight attendants were excellent. Really nice experience except my tv didn’t work.

Overall, the flight was better than the flight I took to go to Florida, which had a bunch of problems. The crew is really nice and the plane was new so it had a small problem when we were on the runway, but the flight itself was great. They even made some time back up, which is always a good thing.

There were multiple delays but JetBlue tried to make the boarding and departure process as quick and efficient as possible. The crew was as detached from reality as could be, meaning: not very friendly and just doing things by the numbers.

I had back trouble prior to my flight and everyone was great about helping me.

40 minute delay before take off after boarding flight. Bright lights throughout night flight due Issues with light panels. In flight Entertainment nonfunctional

Everything was good except for deplaning in NY. Took way too long!!

Jet Blue keeps getting iit wrong. 4 hour mechanical delay followed by terrible boarding experience. This is my third horrific jet blue flight in 2024. I am going to try to avoid this loser in the sky

Surprisingly easy! I was hesitant to try this, but the cost swayed me. I actually felt like I had less stress than all the taxiing and possible delays that occur with short regional flights where you spend less time in the air than getting to and from the plane..

This flight was delayed multiple times and eventually canceled around 2-3ish. Original take off time was around 10:30am. By 3, there were no other options out of Houston, so stuck in Houston for from 3pm - 11am the next day.

Should have video screens Plane audio was poor and without wired connection hard to understand crew. Should serve more than just cups of water and pretzels on six hour flight. Did not see crew rest of flight. Fix charging sockets to retain charging blocks.

I paid $380 for my one-way ticket from California to Minnesota. The fair did not include online check-in. I received instructions from their app to check in at a kiosk. At the kiosk, the boarding pass would not print until an actual person came to verify that I had a personal item and not a carry-on item, On the plane, the person next to me was drunk and allowed to continue to order alcohol. United is garbage I’d rather fly spirit.

The plane was dirty and the in seat air wasn't blowing as planes usually do.

Generally good but there wasn’t any staff available when my luggage didn’t appear at baggage claim in Fresno. It took about half an hour to locate a staff member to open up the locked room where it was being kept.

Do not like the feeling of being in the basic economy. Everyone should feel good no matter what.

All flights were on time and boarding was issue free

Terrible! The plane was old and you are required to connect your own device to their Wi-Fi rather than have entertainment options in the back of the seat in front of you. The Wi-Fi went out during the flight and there was only one plug for the devices every two seats. Three out of five surrounding my family did not work. The seats and spaces under them were so small I could not fit my backpack, which I’ve always brought on flights and fit before no problem. The crew were unpleasant and patronizing.

Great! The plane was decently sized and comfortable. The staff was nice and there was great in flight entertainment

Even though we left CMI late, we mostly made up the time.

Delayed almost 4 hours for a 45 minute flight with no explanation.

Again, multiple delays and I eventually just canceled and drove!

Great crew. We were delayed so that late passengers could get on the flight. Love the bedding in business class. Good food. Great experience.

The CX617 from HK to BKK was delayed more than 1.5 hours.

Horrible - they lied to me about baggage & boarding, even though I specifically spoke to their agents the day before my flight about my issue. When I showed up they did not let me board and stranded me at my airport until I bought a new flight with money I did not have to spend.

All four American Airlines flights I took in last seven days were delayed. Caused me loads of problems, missed meetings, loss of time and money.

American cancelled our flight home. Zero option for hotel, alternative transportation and took 3 hours to find our bags so we could take a 3 hour UBER ride home on our dime. Never flying AA again.

They gave my seat away although it was a connecting flight with them and the flight was a bit delayed.

Flight was cancelled had to move to another gate late again no internet paid for the month and never can use it waste of money

Book cheap flights from Seattle to Portsmouth

Recent round-trip flight deals

6/4Tue
2 stopsSpirit Airlines
22h 51mSEA-BOS
6/11Tue
3 stopsSpirit Airlines
29h 22mBOS-SEA
$188
6/4Tue
2 stopsSpirit Airlines
21h 51mSEA-BOS
6/11Tue
3 stopsSpirit Airlines
29h 22mBOS-SEA
$192
6/4Tue
3 stopsSpirit Airlines
33h 19mSEA-BOS
6/11Tue
3 stopsSpirit Airlines
29h 22mBOS-SEA
$208
8/23Fri
1 stopAmerican Airlines
10h 59mSEA-BOS
9/1Sun
1 stopAmerican Airlines
11h 23mBOS-SEA
$261
5/29Wed
1 stopAmerican Airlines
10h 49mSEA-BOS
6/5Wed
1 stopAmerican Airlines
8h 31mBOS-SEA
$262
6/1Sat
nonstopJetBlue
5h 29mSEA-BOS
6/12Wed
1 stopJetBlue
8h 39mBOS-SEA
$341
5/31Fri
nonstopJetBlue
5h 29mSEA-BOS
6/12Wed
1 stopJetBlue
8h 39mBOS-SEA
$346
6/4Tue
nonstopAlaska Airlines
5h 25mSEA-BOS
6/11Tue
nonstopAlaska Airlines
6h 09mBOS-SEA
$357
5/28Tue
1 stopAlaska Airlines
9h 07mSEA-BOS
6/5Wed
nonstopAlaska Airlines
6h 09mBOS-SEA
$366
5/30Thu
nonstopDelta
5h 28mSEA-BOS
6/8Sat
nonstopDelta
6h 17mBOS-SEA
$372

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Recent one-way flight deals

5/29Wed
2 stopsSpirit Airlines
23h 15mSEA-BOS
$139
7/9Tue
2 stopsSpirit Airlines
22h 30mSEA-BOS
$140
6/5Wed
nonstopAlaska Airlines
5h 24mSEA-BOS
$179
6/8Sat
nonstopAlaska Airlines
5h 24mSEA-BOS
$184
6/9Sun
1 stopAmerican Airlines
7h 37mSEA-BOS
$188
6/6Thu
nonstopDelta
5h 32mSEA-BOS
$189
6/4Tue
1 stopAmerican Airlines
8h 28mSEA-BOS
$198
6/9Sun
nonstopJetBlue
5h 29mSEA-BOS
$204
5/15Wed
1 stopJetBlue
10h 45mSEA-BOS
$214
7/13Sat
nonstopDelta
5h 27mSEA-BOS
$244

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Last minute flights from Seattle to Portsmouth

Last minute flight, train and bus deals

5/10Fri
nonstopJetBlue
5h 29mSEA-BOS
5/14Tue
nonstopJetBlue
6h 05mBOS-SEA
$397
5/8Wed
multi-stop
13h 48mSEA-BOS
5/14Tue
multi-stop
29h 35mBOS-SEA
$425
5/8Wed
multi-stopAmerican Airlines
9h 52mSEA-BOS
5/14Tue
multi-stopAmerican Airlines
11h 02mBOS-SEA
$428
5/10Fri
multi-stopAmerican Airlines
10h 47mSEA-BOS
5/14Tue
multi-stopAmerican Airlines
11h 02mBOS-SEA
$430
5/9Thu
multi-stopUnited Airlines
7h 38mSEA-BOS
5/18Sat
multi-stopUnited Airlines
12h 18mBOS-SEA
$525
5/9Thu
multi-stopUnited Airlines
13h 23mSEA-BOS
5/18Sat
multi-stopUnited Airlines
12h 18mBOS-SEA
$535
5/10Fri
nonstopAlaska Airlines
5h 26mSEA-BOS
5/14Tue
nonstopAlaska Airlines
6h 15mBOS-SEA
$537
5/9Thu
nonstopAlaska Airlines
5h 20mSEA-BOS
5/13Mon
nonstopAlaska Airlines
6h 14mBOS-SEA
$538
5/11Sat
multi-stopDelta
7h 28mSEA-BOS
5/13Mon
nonstopDelta
6h 17mBOS-SEA
$546
5/8Wed
multi-stopDelta
7h 10mSEA-BOS
5/14Tue
nonstopDelta
6h 17mBOS-SEA
$547

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Flights to Portsmouth