Route guide · 2,490 miles
Cheap Flights from Seattle to Boston
SEA → BOS · Nonstop 5h 34m · Live round-trip fares
Plenty of travelers price out Seattle to Boston every day — here's how to beat the average fare. Nonstops run about 5h 34m, and the calendar matters more than the airline. Aim to book 4–8 weeks ahead, stay flexible on the day of the week, and set a free alert so a price drop never slips past you.
Live fares for SEA → BOS are updating. Use the search below for real-time prices.
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See live fares
Updated daily
Flight time
5h 34m
Nonstop, typical
Distance
2,490 mi
SEA → BOS
Book ahead
4–8 weeks
Best window, typically
Nonstop airlines
3
Alaska Airlines, Delta Air Lines & more
Nonstop flights from Seattle to Boston
Nonstop flights from Seattle to Boston are flown by Alaska Airlines, Delta Air Lines, United Airlines. The 2,490-mile trip takes about 5h 34m gate to gate, and nonstops are usually cheapest when booked 4–8 weeks ahead.
Booking insights: Seattle → Boston
- Distance: 2,490 miles · nonstop flight time: 5h 34m.
- Cheapest upcoming week in the live data starts around Oct 15, with fares from $151.
- Fares tend to bottom out when you book about 4–8 weeks ahead — earlier than that rarely helps, later usually hurts.
- If your dates flex by a day or two, shifting to a midweek departure is the easiest saving there is.
- A free fare alert beats daily checking: we watch this route and ping you when prices drop.
Price trend
Cheapest departure weeks ahead
Near-term departures around Oct 15 are currently the cheapest on this route. Based on recent fares found for this route; prices change quickly.
Cheapest month · Seattle → Boston
October 2026
Every date's recent round-trip fare, at a glance.
Fares from
$151
Cheapest: Tue, Oct 20 — $151 · Priciest: Oct 23 — $264
Get this fare →Recent fares found for specific dates in October 2026. Blank days had no recent fare in our data — ask our team and we'll check them for you.
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Flying from Seattle to Boston: what you need to know
The flight
This is one of the long ones: 2,490 miles from SEA to BOS, about 5h 34m on a nonstop. Treat it like a short international flight — real meal plan, charged devices, a layer for the cabin — and the hours go much easier.
Airlines on this route
Alaska Airlines, Delta Air Lines and United Airlines fly this route nonstop. That matters more than it sounds: the cheapest fare on one carrier is rarely the same product as the cheapest on another. Checked-bag fees, free seat selection and change rules all differ, so compare the full trip cost before you pick a winner. See our airline guides for exactly what each carrier charges — then send an enquiry and we'll confirm the all-in price for your dates.
Leaving from Seattle (SEA)
Plan to be at the airport two hours before a domestic departure — ninety minutes can work at smaller airports outside peak times, but security lines are the one variable you can't control. If you're checking a bag, add time rather than cutting it close. Our Seattle airport guide covers terminals, parking and ground transport so you can plan the trip to the airport, not just the flight.
Arriving in Boston (BOS)
Before you land, know how you're getting from the airport to where you're staying — it's the part of the trip people forget to plan. The Boston airport guide lays out your ground options, from transit and shuttles to rideshares and rental cars. Flying back the other way? Check Boston to Seattle fares — prices on the return direction often move on a different rhythm.
When to book
For a trip of 2,490 miles, booking 4–8 weeks ahead typically lands you in the sweet spot. Leave it to the final two weeks and prices usually climb as the cheapest seats sell out. If your dates are flexible, midweek departures are where the lower fares hide on most domestic routes.
Good to know before you go
- Screenshot your fare before you enquire — prices move, and a saved fare helps our team match or beat it.
- Flexible dates? Search a few days either side — one day can change the fare a lot.
- Morning flights are delayed less often than evening ones — earlier departures have the best on-time record.
- Basic economy fares often exclude checked bags and seat selection. Price the whole trip, not the headline fare.
- Get to the airport two hours before departure; security, not the flight, is the part that runs late.
Seattle to Boston flight FAQs
How long is the flight from SEA to BOS?
Plan on about 5h 34m in the air for a nonstop from Seattle to Boston — the route runs roughly 2,490 miles. Connecting flights typically add 2–4 hours.
Are there nonstop flights from Seattle to Boston?
Alaska Airlines, Delta Air Lines, United Airlines typically operate nonstop flights from SEA to BOS. Nonstops are usually cheapest when booked 4–8 weeks ahead of departure.
What is the cheapest month to fly from Seattle to Boston?
Travelers usually find the gentlest prices away from peak periods — think post-holiday January and the early-fall weeks. Midweek dates inside those windows are cheaper still.
How much are last minute flights from SEA to BOS?
Book inside the final week and you'll usually pay a premium on SEA to BOS. Fares booked 4–8 weeks ahead are almost always kinder.
What is a good round-trip deal from Seattle to Boston?
A good deal is anything at or below the recent fares shown above. Set a free Airfare Deal alert and we'll ping you the moment fares drop.
Which airlines fly from Seattle to Boston?
You'll mainly see Alaska Airlines, Delta Air Lines, United Airlines on Seattle to Boston. Checking each against the live fares below is the surest way to find the lowest price for your dates.
How early should I get to Seattle airport for this flight?
Plan on two hours before departure for a domestic flight — ninety minutes can work at smaller airports outside peak times. If you're checking a bag, earlier is better; the bag-drop line, not the flight, is what runs late.
Do the cheapest fares on this route include a checked bag?
Usually not. Basic economy fares on most airlines include a carry-on but charge extra for checked bags, and seat selection can cost more too. Add up the real total before comparing — a slightly higher regular fare sometimes works out cheaper. Our team confirms the full breakdown with you before you pay.
More cheap flights from Seattle
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