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Find cheap flights from Seattle to Portsmouth from $99

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 8/20. 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
Sun 6/16
Sun 6/23

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Good to know

Low season

January

High season

August

Cheapest flight

$99
Best time to beat the crowds with an average 40% drop in price.
Most popular time to fly with an average 20% 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 10m.

  • How many flights are there between Seattle and Portsmouth?

    42 direct flights run between Seattle and Portsmouth on a daily basis. On average, there are about 296 departures each week.

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

    Consider leaving on a Tuesday and avoid Sundays if you are looking for the best rates. For your return to Seattle, 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 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 $99. Spirit Airlines offered a round-trip connection from $197 and Sun Country Air from $260.

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 9162 reviews
7.3Food
8.6Crew
7.3Entertainment
8.2Boarding
7.9Comfort
Airline reviews

Why do you ask about food when only a snack is served? Actual food needs to be bought.

8.0 ExcellentAnonymous, May 2024SEA - PHL
Read more about Alaska Airlines reviews

Why do you ask about food when only a snack is served? Actual food needs to be bought.

There was an older male crew member that was very rude to me when doing the last checks before pulling back from the terminal. There is a polite way to tell someone to put their bag under the seat. It was Mother’s Day and my mom has recently passed so it was a tough morning for me in general. There was no need to make for the snide remark “ I don’t know how many times we have said this already” as you walked away. I had held it together all morning and this interaction brought me to tears. love Alaska Airlines and this is the first time I’ve had a negative experience.

Alway a a breeze! And great mountain views on left side of plane during entire flight!

another delayed flight. no one at the desk kept us updated. we found out by an email as the desk was not even staffed up to expected takes off

They canceled my flight going back to SF after I was at the airport. Wanted me to take a flight 14 hours later. Not a happy camper.

Service was excellent. Staff at check in cleared hurdles for me so I could travel with my service animal.

Flight cancelled an hour before takeoff due to "unscheduled maintenance". New flight makes me have to wait for 5 hours in the airport, at a gate totally on the other side of where I'm at, requiring me to take a tram to get from the N terminal, to the C terminal. After waiting for 5 hours I'm informed my new flight is no longer at the gate I'm at, but instead is back in the N terminal where I was previously.

Delayed an hour and sat without updates. Ended up an hour late to destination

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 plane from SNA wouldn’t start after 5 tries. The team gave me an option of flying direct from LAX and giving me a Lyft ride there! Perfect!

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.

Going through JFK’s security is a mess. The TSA security said no shoes on the bins. So, we place our shoes in the belt and they came out all over the belt. Boarding was delayed and Flight as well.

Safe and on time were the positives. The plane wasn't cleaned before boarding, there was garbage and food on the floor and in the seat pocket. The TV screen was small and the picture fuzzy, audio quality was poor. Seatbelt was fraying and seat did not recline properly. No charging ports near the seats,

Confusing. Delay updates were out of whack At one point it said my flight was 25 hours. Three gate changes and two delays only to change back to original departure time. Gate announcer and on board flight attendant (Alejandro) making the announcements was impossible to understand due to accent and speed of speech. After beverage service the rear flight attendants sat back there on their phones. No refills no checking in, one sweep through for trash collection. Very impersonal. Bring back Coke products

Delayed departure. Delayed after landing pulling into gate. Delay due to sky bridge malfunction

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.

No lounge access with “United First” ticket. False alarm about late flight, jeopardizing connection. Wrong meal. Loose power socket would not hold plug, could not charge device. In-flight access to text messaging did not work. Toilet seat on plane would not stay up.

We ended up with seats in the very back. So they did not recline. Have no idea why, we reserved and checked in very early. The isles were very narrow and the seats had very little leg room. But they did give us water, and a snack.

Check in etc was very good. As for on the plane, it was like flying in a freezer. It was so cold, i have flown for years and never been so cold on a plane. Staff on board said its always cold when flying which is a load of rubbish. They wouldnt put any heating on and now i have the flu because of this .

I’ve had a couple flights this week on United that were delayed by an hour or more

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.

The flight was short. However, my bag was delayed and was put on another flight.

Flight attendant was incredible. Very efficient, friendly and pleasant. Patricia was one of the best I have ever seen. Please give her a big raise!

LIT to DFW - 3 hours late; the entire plane had been boarded before they told us there was a delay due to a weather-related ground stop in Dallas. DFW to MAY - 2+ hours late due to A/C needing to be repaired after everyone had boarded, then when we finally reach the runway, the First Officer timed out and we had to taxi all the way back to the gate and wait for a new one. I arrived in New Orleans 5+ hours later than I should have. Return flights were completely cancelled; rebooked through the app to fly through CLT instead of DFW. MSY to CLT had no issues, but CLT to LIT was delayed 1.25 hrs because flight attendants had not arrived to the airport yet. At least they didn’t make us all sit on the plane to wait for them. I should have driven.

Tray table was filthy when I sat down. I needed to have someone come clean it because there was food and stains on it WiFi didn’t work after paying for in-flight WiFi. Food was terrible and was not filling at all Chicken was rubbery Flight attendant had an attitude, interrupted me and wasn’t able to answer basic questions about the food selection such as “does the chicken have red sauce in it”. If your flight attendants are not going to know what is in the meals so we can make an educated decision based on dietary restrictions, they shouldn’t be on the plane. My 1.5 year old niece was sleeping and dropped her binkie. I went on the ground under the chairs looking for it. It was at that time that she came up to me as I’m CLEARLY on all 4s with a flashlight and said “I need to get by”. I said one moment please I’m getting something from under the seat (while my head was literally under the seat). Her reply was “no you need to move now” and proceeded to almost push me out of the way. I looked up and all I saw was her toes under my eyes. When I looked in front of me, her private parts were inches away from my face. I then made a comment “you couldn’t waited 2 seconds?” and her response was, “no I need to use the bathroom”. I understand that and would never want to be the reason someone couldn’t get to the bathroom but I was under the seat. She could’ve gone around the other way instead of harassing me, basically placing her private parts on my head and borderline pushing me out of the way. You don’t pay that much for this deplorable experience. This was by far the worst experience I have ever had on American. I will be absolutely thinking twice and thrice about flying American Airlines again. I would rather pay more to fly delta because at least I know their WiFi will work and their flight attendants won’t have a shitty attitude for no reason, nor will they act the way this woman did. Unacceptable.

Liked - nothing. Disliked - delayed 35+ min sitting on the plane. Caused me to miss my connection in Charlotte. American Airlines is the worst US Air Carrier company with atrocious customer service.

Worst situation ever! I booked my tickets for this trip on Alaska Airlines. I guess AA is a partner and we flew nonstop from Eugene to PHX on an AA jet. I had to pay for luggage from PHX to EUG. And this was an Alaska Airlines reservation paid for with Alaska airlines credit card! Got to the PHX airport and was not able to check bags because of some weird issue with the AA software. My reservation had to be the-entered by the agent. I will never pick another American Airlines flight on the Alaska Airlines website. While on vacation, I tried to upgrade our seats for the trip home. The request just buffered and never went through. I tried four times and was charged four times on my credit card. The card was charged but the seats were never changed. What a wreck!

Left from gate 30 minutes before flight. Never been late to a flight ever. It says 15 minutes before explicitly on the ticket.

I like the boarding process, it was fast. The seat doesn’t have a TV for a long flight and food wasn’t served, just snacks.

Use planes with TVs on flights over 4 hours. The free entertainment was a cheap in between solution for a very long flight that you don't even bother providing meals or decent snacks.

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

Book cheap flights from Seattle to Portsmouth

Recent round-trip flight deals

8/20Tue
1 stopSpirit Airlines
10h 37mSEA-BOS
8/27Tue
1 stopSpirit Airlines
16h 21mBOS-SEA
$197
8/19Mon
2 stopsSpirit Airlines
23h 31mSEA-BOS
8/26Mon
1 stopSpirit Airlines
16h 21mBOS-SEA
$231
8/13Tue
1 stopAmerican Airlines
11h 43mSEA-BOS
8/20Tue
1 stopAmerican Airlines
12h 33mBOS-SEA
$275
9/11Wed
1 stopAmerican Airlines
7h 47mSEA-BOS
9/17Tue
1 stopAmerican Airlines
9h 28mBOS-SEA
$283
9/21Sat
nonstopAlaska Airlines
5h 15mSEA-BOS
9/25Wed
nonstopAlaska Airlines
6h 14mBOS-SEA
$307
9/11Wed
nonstopJetBlue
5h 23mSEA-BOS
9/17Tue
1 stopJetBlue
12h 39mBOS-SEA
$316
9/11Wed
nonstopJetBlue
5h 23mSEA-BOS
9/17Tue
nonstopJetBlue
6h 21mBOS-SEA
$317
10/1Tue
nonstopAlaska Airlines
5h 13mSEA-BOS
10/5Sat
nonstopAlaska Airlines
6h 22mBOS-SEA
$337
9/30Mon
nonstopDelta
5h 20mSEA-BOS
10/1Tue
nonstopDelta
6h 21mBOS-SEA
$357
5/30Thu
nonstopDelta
5h 28mSEA-BOS
6/11Tue
nonstopDelta
6h 17mBOS-SEA
$407

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Recent one-way flight deals

8/20Tue
1 stopSpirit Airlines
10h 37mSEA-BOS
$99
6/4Tue
2 stopsSpirit Airlines
21h 51mSEA-BOS
$113
9/25Wed
1 stopAmerican Airlines
7h 44mSEA-BOS
$142
8/19Mon
1 stopAmerican Airlines
7h 26mSEA-BOS
$143
10/15Tue
nonstopAlaska Airlines
5h 15mSEA-BOS
$146
9/3Tue
nonstopJetBlue
5h 20mSEA-BOS
$159
6/13Thu
nonstopJetBlue
5h 28mSEA-BOS
$184
6/10Mon
nonstopDelta
5h 27mSEA-BOS
$194
5/28Tue
nonstopDelta
5h 28mSEA-BOS
$209
8/11Sun
1 stopAlaska Airlines
20h 35mSEA-BOS
$212

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Last minute flights from Seattle to Portsmouth

Last minute flight, train and bus deals

5/22Wed
multi-stop
13h 48mSEA-BOS
5/29Wed
multi-stop
19h 37mBOS-SEA
$411
5/22Wed
multi-stopSun Country Air
13h 48mSEA-BOS
5/31Fri
multi-stopSun Country Air
14h 20mBOS-SEA
$445
5/22Wed
multi-stopDelta
7h 10mSEA-BOS
5/29Wed
nonstopDelta
6h 17mBOS-SEA
$536
5/21Tue
nonstopAlaska Airlines
5h 26mSEA-BOS
5/29Wed
nonstopAlaska Airlines
6h 05mBOS-SEA
$537
5/21Tue
nonstopAlaska Airlines
5h 26mSEA-BOS
5/25Sat
multi-stopAlaska Airlines
9h 53mBOS-SEA
$546
5/21Tue
multi-stopAmerican Airlines
10h 49mSEA-BOS
5/28Tue
multi-stopAmerican Airlines
10h 35mBOS-SEA
$553
5/20Mon
multi-stopAmerican Airlines
8h 57mSEA-BOS
5/29Wed
multi-stopAmerican Airlines
9h 50mBOS-SEA
$555
5/22Wed
nonstopDelta
5h 37mSEA-BOS
5/27Mon
nonstopDelta
6h 17mBOS-SEA
$557
5/19Sun
nonstopJetBlue
5h 29mSEA-BOS
8/11Sun
nonstopJetBlue
6h 12mBOS-SEA
$677
5/19Sun
multi-stopJetBlue
10h 45mSEA-BOS
8/11Sun
nonstopJetBlue
6h 12mBOS-SEA
$686

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Flights to Portsmouth