Flights Boston → Seattle
As of October 2026, economy flights from Boston to Seattle have a typical range USD 320–1624, median USD 458. Full range across all 156 offers: USD 320–2520. We analyzed 156 offers from 9 airlines in a single price check.
Preview snapshot — prices change. Search for live results.
Data collected by LetsFG's multi-source price checks — every airline and the major booking sites checked for this route. How we collect data →
Best offers by airline: Boston → Seattle
Based on 156 offers · October 2026. Prices and availability change — run a live search to confirm.
Bag & seat fees: Boston → Seattle
Add-on pricing from the cheapest available offer per airline · October 2026 · USD
| Airline | Carry-on | Checked bag | Seat selection |
|---|---|---|---|
| United | Included | USD 35 | — |
| American Airlines | Included | USD 35 | — |
| JetBlue | — | USD 35 | — |
| American | — | USD 55 | — |
| United | — | USD 50 | — |
| Alaska Airlines | — | USD 35 | — |
| Southwest Airlines | Included | Included | — |
| Delta | Included | USD 35 | — |
| JetBlue | — | USD 45 | — |
Fees are estimates from the prices we checked and may not reflect your specific itinerary, booking class, or payment method. Run a live search for exact pricing.
How much do flights from Boston to Seattle cost?
Based on 156 offers · October 2026
Boston to Seattle flights ranged from USD 320 to USD 2520 across 156 offers analyzed in October 2026. The chart below shows how prices distributed across all 156 offers.
These 156 offers (October 2026) span multiple departure dates and booking windows — your travel dates may fall anywhere in this distribution. Only a live search shows where your specific trip lands.
50% of offers priced between USD 321 and USD 529
What hidden fees do Boston to Seattle flights charge?
Ancillary fees — bags, seat selection, and payment surcharges — can add 10–25% to the base fare on Boston to Seattle routes. The breakdown below is based on 156 offers analyzed in October 2026.
| Carrier | Avg fee (USD) | % of base fare |
|---|---|---|
| UA | 43 | 6% |
| AA | 47 | 10% |
| B6 | 45 | 10% |
| American | 55 | 17% |
| United | 50 | 16% |
| AS | 45 | 8% |
| WN | 0 | 0% |
| DL | 32 | 4% |
| JetBlue | 45 | 10% |
American: base ~USD 266 + fees USD 55 = ~USD 321 total. Delta Air Lines: base ~USD 426 + fees USD 32 = ~USD 458 total.
American's USD 55 ancillary fees narrow the gap with Delta Air Lines's lower-fee model — the USD 160 base difference shrinks to USD 137 after fees. Always compare total cost, not just the advertised base fare.
Estimates based on median total minus average ancillary fee. Actual base fares vary by itinerary.American charges 1.7x more in ancillary fees than DL on this route. Compare total-cost options when booking.
Run your search to see itemized fees for your itineraryWhich airline is cheapest from Boston to Seattle?
9 airlines flew Boston to Seattle in this dataset. Knowing the airline isn't enough — the typical fare range below shows how far prices swing on each one. Median and range include all fees we recorded.
| Airline | Offers | Typical range (USD) | Median (USD) | Fees (USD) |
|---|---|---|---|---|
 American | 6 | — | 321 | 55 (17%) |
 United | 1 | — | 321 | 50 (16%) |
 United Airlines | 35 | 320–1935 | 366 | 43 (12%) |
 B6 | 3 | 330–590 | 367 | 45 (12%) |
 Southwest Airlines | 7 | 448–529 | 448 | 0 (0%) |
 JetBlue | 1 | — | 449 | 45 (10%) |
 Delta Air Lines | 39 | 458–2274 | 458 | 32 (7%) |
 Alaska Airlines | 14 | 439–666 | 464 | 45 (10%) |
 American Airlines | 50 | 320–479 | 476 | 47 (10%) |
Where do the best Boston → Seattle prices come from?
We checked direct airlines, travel agencies, and meta-search for this route. On this route the lowest median came from travel agency sources, but the cheapest channel shifts by route and date — which is exactly why a live search across all of them wins.
We compare every airline and the major booking sites but never disclose which — that's our edge. Prices are the ones we observed and aren't official data from any platform. Run a live search and we bring you the cheapest, wherever it is.
Key facts: Boston to Seattle flights
- Full-service carriers on Boston–Seattle cost 1.0x more than budget airlines (USD 401 vs USD 421 median; overall median USD 458).
- American charges 1.7x more in ancillary fees than DL — USD 55 vs USD 32 avg per booking.
- The same route priced USD 1953 apart depending on where it was booked — the lowest median was USD 321. We search every airline and the major booking sites at once so you always see that lowest price.
Frequently asked questions
- How much does a flight from Boston to Seattle cost?
- Based on 156 offers analyzed, Boston to Seattle flights range from USD 320 to USD 2520, with a median price of USD 458. Search for your specific dates →
- What hidden fees should I expect on Boston to Seattle flights?
- On average, ancillary fees (bags, seat selection) add USD 40 to the base fare on Boston to Seattle flights. See itemized fees for your itinerary →
- Which airline is cheapest on Boston to Seattle including all fees?
- American has the lowest median fare on Boston to Seattle at USD 321 (median across 6 offers in our snapshot). Check which airline wins on your dates →
- Which booking site has the cheapest Boston–Seattle flights?
- It depends on your dates — no single site is always cheapest. We search every airline and the major booking sites at once (travel agencies and meta-search included) and surface whichever is lowest; the best median in this snapshot was USD 321. Run a live search and we'll find the cheapest for you →
- Why do prices vary so much on Boston to Seattle routes?
- Boston to Seattle has 9 airlines competing, creating a price range from USD 320 to USD 2520 across 156 offers. Prices on this route change with booking timing, advance purchase, and ancillary add-ons. Find where your trip lands in the distribution →
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