Booking tips for Denver → Seattle
For most economy fares on Denver to Seattle, booking roughly three to eight weeks ahead tends to hit the sweet spot on price, with last-minute fares rising sharply in the final two weeks. Tuesday, Wednesday, and Saturday departures are usually cheaper than Fridays and Sundays, and early-morning or late-evening flights often undercut midday slots. If you are traveling light, the difference between a basic economy fare with carry-on only and a standard fare with a checked bag can be significant. Compare both options before booking, and also check whether DEN or SEA has a nearby alternative airport that might offer better fares on the same dates.
| Carrier | Sightings / 90d | Safety events |
|---|---|---|
| United Airlines | 6 sightings | No recorded events |
| Southwest Airlines | 3 sightings | No recorded events |
| Delta Air Lines | 2 sightings | No recorded events |
| Alaska Airlines | 2 sightings | No recorded events |
Planning DEN → SEA
DEN to SEA is a medium-haul route of 1,645 km (1,022 mi). See the return SEA → DEN route.
Alternative airports near Denver: Buckley (BFK) — 19 km, Denver (APA) — 36 km, Broomfield-CO (BJC) — 38 km.
Alternative airports near Seattle: Seattle (BFI) — 9 km, Renton (RNT) — 9 km, Tacoma (TIW) — 28 km.
Frequently asked questions about Denver → Seattle
How long does the flight from Denver to Seattle take?
Flight time from Denver (DEN) to Seattle (SEA) depends on routing, aircraft type, and whether the flight is direct or connecting. A direct flight typically reflects great-circle distance plus winds, while one-stop options can add several hours depending on the layover airport. Check the exact duration in the search results above, where we show block time per itinerary along with stop count.
Which airlines fly from Denver to Seattle?
Airline availability for DEN to SEA changes by season and sometimes week to week as carriers adjust capacity. Our search above pulls live schedules and returns the airlines currently selling this route, both direct and connecting. Codeshare and interline itineraries are included, so you may see results operated by one carrier but sold by another.
Are there direct flights from Denver to Seattle?
Direct (nonstop) availability on DEN to SEA varies by date, day of week, and season. Busy city pairs usually have multiple daily nonstops, while thinner routes may only have direct service a few days per week or only during peak seasons. Use our search above with flexible dates to see which days actually have nonstop options.
What is the cheapest month to fly from Denver to Seattle?
Prices on DEN to SEA shift with seasonality, school holidays, and major events at both ends. Our 12-month price calendar below the search results shows the lowest fare found per departure date, which makes it easy to spot the cheapest weeks at a glance. Flexibility of a few days around your target date often unlocks significantly lower fares.
Plan the rest of your trip to Seattle
- Things to doBook attractions and tours in Seattle.
- Travel insuranceCover delays, baggage, and medical costs abroad.
- eSIM dataGet online in United States the moment you land.
- Car rentalCompare rental cars across global suppliers.
- Airport transferBook a private ride from the airport in advance.
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