Flights Chicago → Seattle
As of November 2026, economy flights from Chicago to Seattle have a typical range USD 248–392, median USD 310. Full range across all 621 offers: USD 247–627. We analyzed 621 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: Chicago → Seattle
Based on 621 offers · November 2026. Prices and availability change — run a live search to confirm.
Bag & seat fees: Chicago → Seattle
Add-on pricing from the cheapest available offer per airline · November 2026 · USD
| Airline | Carry-on | Checked bag | Seat selection |
|---|---|---|---|
| Delta | Included | USD 35 | — |
| American Airlines | Included | USD 35 | — |
| Alaska | — | USD 90 | — |
| Alaska Airlines | Included | USD 35 | — |
| Delta | — | USD 90 | — |
| United | Included | USD 35 | — |
| Southwest Airlines | Included | Included | — |
| Southwest | — | USD 90 | — |
| Frontier Airlines | — | — | — |
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 Chicago to Seattle cost?
Based on 621 offers · November 2026
Chicago to Seattle flights ranged from USD 247 to USD 627 across 621 offers analyzed in November 2026. The chart below shows how prices distributed across all 621 offers.
These 621 offers (November 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 257 and USD 371
What hidden fees do Chicago to Seattle flights charge?
Ancillary fees — bags, seat selection, and payment surcharges — can add 10–25% to the base fare on Chicago to Seattle routes. The breakdown below is based on 621 offers analyzed in November 2026.
| Carrier | Avg fee (USD) | % of base fare |
|---|---|---|
| DL | 45 | 16% |
| AA | 45 | 15% |
| Alaska | 90 | 36% |
| AS | 37 | 11% |
| Delta | 90 | 35% |
| UA | 45 | 13% |
| WN | 8 | 2% |
| Southwest | 90 | 30% |
| F9 | 10 | 3% |
Alaska: base ~USD 157 + fees USD 90 = ~USD 247 total. Southwest Airlines: base ~USD 373 + fees USD 8 = ~USD 381 total.
Alaska's USD 90 ancillary fees narrow the gap with Southwest Airlines's lower-fee model — the USD 216 base difference shrinks to USD 134 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.Fee levels vary significantly across carriers on this route — some carriers charge 50%+ above the base fare in ancillary fees.
Run your search to see itemized fees for your itineraryWhich airline is cheapest from Chicago to Seattle?
9 airlines flew Chicago 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) |
|---|---|---|---|---|
 Alaska | 8 | — | 247 | 90 (36%) |
 Delta | 1 | — | 257 | 90 (35%) |
 Delta Air Lines | 133 | 257–321 | 266 | 45 (17%) |
 Southwest | 3 | — | 297 | 90 (30%) |
 Alaska Airlines | 75 | 252–537 | 300 | 37 (12%) |
 American Airlines | 186 | 247–366 | 307 | 45 (15%) |
 Frontier Airlines | 2 | 314–316 | 315 | 10 (3%) |
 United Airlines | 64 | 281–387 | 326 | 45 (14%) |
 Southwest Airlines | 149 | 322–403 | 381 | 8 (2%) |
Where do the best Chicago → 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: Chicago to Seattle flights
- Full-service carriers on Chicago–Seattle cost 0.9x more than budget airlines (USD 284 vs USD 331 median; overall median USD 310).
- Alaska charges 10.6x more in ancillary fees than WN — USD 90 vs USD 8 avg per booking.
- The same route priced USD 300 apart depending on where it was booked — the lowest median was USD 247. 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 Chicago to Seattle cost?
- Based on 621 offers analyzed, Chicago to Seattle flights range from USD 247 to USD 627, with a median price of USD 310. Search for your specific dates →
- What hidden fees should I expect on Chicago to Seattle flights?
- On average, ancillary fees (bags, seat selection) add USD 36 to the base fare on Chicago to Seattle flights. See itemized fees for your itinerary →
- Which airline is cheapest on Chicago to Seattle including all fees?
- Alaska has the lowest median fare on Chicago to Seattle at USD 247 (median across 8 offers in our snapshot). Check which airline wins on your dates →
- Which booking site has the cheapest Chicago–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 247. Run a live search and we'll find the cheapest for you →
- Why do prices vary so much on Chicago to Seattle routes?
- Chicago to Seattle has 9 airlines competing, creating a price range from USD 247 to USD 627 across 621 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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