Flights Denver → Seattle
As of September 2026, economy flights from Denver to Seattle have a typical range USD 150–676, median USD 169. Full range across all 92 offers: USD 111–4995. We analyzed 92 offers from 8 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: Denver → Seattle
Based on 92 offers · September 2026. Prices and availability change — run a live search to confirm.
Bag & seat fees: Denver → Seattle
Add-on pricing from the cheapest available offer per airline · September 2026 · USD
| Airline | Carry-on | Checked bag | Seat selection |
|---|---|---|---|
| Frontier Airlines | — | — | — |
| Alaska | — | USD 49 | — |
| Southwest Airlines | — | — | — |
| Delta | — | USD 45 | — |
| United | Included | USD 35 | — |
| American Airlines | Included | USD 35 | — |
| Alaska Airlines | Included | USD 35 | — |
| United | — | USD 50 | — |
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 Denver to Seattle cost?
Based on 92 offers · September 2026
Denver to Seattle flights ranged from USD 111 to USD 4995 across 92 offers analyzed in September 2026. The chart below shows how prices distributed across all 92 offers.
These 92 offers (September 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 163 and USD 263
What hidden fees do Denver to Seattle flights charge?
Ancillary fees — bags, seat selection, and payment surcharges — can add 10–25% to the base fare on Denver to Seattle routes. The breakdown below is based on 92 offers analyzed in September 2026.
| Carrier | Avg fee (USD) | % of base fare |
|---|---|---|
| F9 | 10 | 8% |
| Alaska | 49 | 33% |
| WN | 0 | 0% |
| DL | 48 | 26% |
| UA | 46 | 25% |
| AA | 45 | 9% |
| AS | 45 | 5% |
| United | 50 | 30% |
Alaska: base ~USD 101 + fees USD 49 = ~USD 150 total. Frontier Airlines: base ~USD 127 + fees USD 10 = ~USD 137 total.
Alaska's USD 49 ancillary fees narrow the gap with Frontier Airlines's lower-fee model — the USD 26 base difference shrinks to USD 13 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 Denver to Seattle?
8 airlines flew Denver 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.
Even on the cheapest airline (Frontier Airlines), fares ranged USD 117–137 in this snapshot. Your exact price depends on your dates and how far ahead you book — run a live search to see your number →
| Airline | Offers | Typical range (USD) | Median (USD) | Fees (USD) |
|---|---|---|---|---|
 Frontier Airlines | 7 | 117–137 | 137 | 10 (7%) |
 Alaska | 3 | — | 150 | 49 (33%) |
 Southwest Airlines | 24 | 163–169 | 163 | 0 (0%) |
 United Airlines | 14 | 156–271 | 166 | 46 (28%) |
 United | 1 | — | 167 | 50 (30%) |
 Delta Air Lines | 12 | 153–188 | 188 | 48 (25%) |
 Alaska Airlines | 15 | 188–3206 | 267 | 45 (17%) |
 American Airlines | 16 | 163–697 | 676 | 45 (7%) |
Where do the best Denver → Seattle prices come from?
We checked direct airlines, travel agencies, and meta-search for this route. On this route the lowest median came from meta-search 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: Denver to Seattle flights
- Full-service carriers on Denver–Seattle cost 1.8x more than budget airlines (USD 269 vs USD 150 median; overall median USD 169).
- United charges 5.0x more in ancillary fees than F9 — USD 50 vs USD 10 avg per booking.
- The same route priced USD 31 apart depending on where it was booked — the lowest median was USD 138. 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 Denver to Seattle cost?
- Based on 92 offers analyzed, Denver to Seattle flights range from USD 111 to USD 4995, with a median price of USD 169. Search for your specific dates →
- What hidden fees should I expect on Denver to Seattle flights?
- On average, ancillary fees (bags, seat selection) add USD 31 to the base fare on Denver to Seattle flights. See itemized fees for your itinerary →
- Which airline is cheapest on Denver to Seattle including all fees?
- Frontier Airlines has the lowest median fare on Denver to Seattle at USD 137 (median across 7 offers in our snapshot). Check which airline wins on your dates →
- Which booking site has the cheapest Denver–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 138. Run a live search and we'll find the cheapest for you →
- Why do prices vary so much on Denver to Seattle routes?
- Denver to Seattle has 8 airlines competing, creating a price range from USD 111 to USD 4995 across 92 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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