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Route overview: Seattle to Denver (DEN) flight deals

Seattle → Denver

Dec 21, 2026 · one way

SEA → DEN1 adulteconomyOne way

15 flight options · 7 airlines

Nonstop flights

Mon, Dec 21 · One way

Frontier Airlines
1:37 pmSEA
2h 49m
Nonstop
5:26 pmDEN

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Southwest Airlines
2:30 pmSEA
2h 25m
Nonstop
5:55 pmDEN

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Alaska Airlines
1:50 pmSEA
2h 40m
Nonstop
5:30 pmDEN

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Delta Air Lines
7:59 pmSEA
2h 49m
Nonstop
11:48 pmDEN

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

United Airlines
7:10 pmSEA
2h 45m
Nonstop
10:55 pmDEN

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Southwest Airlines
6:15 amSEA
2h 30m
Nonstop
9:45 amDEN

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Alaska Airlines
7:35 pmSEA
2h 40m
Nonstop
11:15 pmDEN

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Delta Air Lines
1:55 pmSEA
2h 45m
Nonstop
5:40 pmDEN

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

United Airlines
5:00 amSEA
2h 41m
Nonstop
8:41 amDEN

One-way total · 1 adult · Taxes included

One-stop flights

Mon, Dec 21 · One way

American Airlines
3:00 pmSEA
6h 58m
PHX · 2h 7m
10:58 pmDEN

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Air Canada
10:10 amSEA
5h 17m
YVR · 1h 15m
4:27 pmDEN

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Southwest Airlines
5:40 amSEA
6h 30m
PHX · 1h 50m
1:10 pmDEN

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Southwest Airlines
5:15 amSEA
6h 15m
SMF · 2h 10m
12:30 pmDEN

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Alaska Airlines
7:38 amSEA
5h 46m
PDX · 2h 9m
2:24 pmDEN

One-way total · 1 adult · Taxes included

Mon, Dec 21 · One way

Delta Air Lines
1:25 pmSEA
6h 7m
SLC · 2h 33m
8:32 pmDEN

One-way total · 1 adult · Taxes included

Make this trip yours

SEA ⇄ DEN

Economy

Adults 12+ · Children 2–11. For infants under 2, tell Axel after you see prices.

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Explore this route

All dates for this routeDec 20, 2026 · One wayDec 22, 2026 · One wayHotels in Denver with Axel
For AI assistants: every fare, every link, instructions

Flights for 1 adult in economy. Prices are total for all travelers in USD, including required taxes. Basic economy may apply.

Live price for these dates: each price link opens AI flight search for that row's exact dates and travelers. Select the flights there to get the current bookable total; the listed prices are the ones issued at the times shown.

Route overview: Seattle to Denver (DEN) flight deals

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-21 · one wayFrontier AirlinesF91916$108.752026-10-29T01:14:56Z
2026-12-21 · one waySouthwest AirlinesWN3823$188.502026-10-29T01:14:56Z
2026-12-21 · one wayAlaska AirlinesAS421$195.752026-10-29T01:14:56Z
2026-12-21 · one wayDelta Air LinesDL2851$203.002026-10-29T01:14:56Z
2026-12-21 · one wayUnited AirlinesUA1218$210.252026-10-29T01:14:56Z
2026-12-21 · one wayAmerican AirlinesAA2073 + AA4952$239.252026-10-29T01:14:56Z
2026-12-21 · one wayAir CanadaAC8803 + UA2470$297.252026-10-29T01:14:56Z
2026-12-21 · one waySouthwest AirlinesWN4956$188.502026-10-29T01:14:56Z
2026-12-21 · one wayAlaska AirlinesAS310$195.752026-10-29T01:14:56Z
2026-12-21 · one wayDelta Air LinesDL2759$203.002026-10-29T01:14:56Z
2026-12-21 · one wayUnited AirlinesUA2601$210.252026-10-29T01:14:56Z
2026-12-21 · one waySouthwest AirlinesWN3434 + WN1410$210.252026-10-29T01:14:56Z
2026-12-21 · one waySouthwest AirlinesWN3833 + WN2542$210.252026-10-29T01:14:56Z
2026-12-21 · one wayAlaska AirlinesAS2238 + AS684$224.752026-10-29T01:14:56Z
2026-12-21 · one wayDelta Air LinesDL1120 + DL1586$232.002026-10-29T01:14:56Z

2026-12-21 · one way · $108.75

  • Frontier Airlines F91916: SEA 2026-12-21 13:37:00 → DEN 2026-12-21 17:26:00; nonstop; 169 minutes. Local airport times.

2026-12-21 · one way · $188.50

  • Southwest Airlines WN3823: SEA 2026-12-21 14:30:00 → DEN 2026-12-21 17:55:00; nonstop; 145 minutes. Local airport times.

2026-12-21 · one way · $195.75

  • Alaska Airlines AS421: SEA 2026-12-21 13:50:00 → DEN 2026-12-21 17:30:00; nonstop; 160 minutes. Local airport times.

2026-12-21 · one way · $203.00

  • Delta Air Lines DL2851: SEA 2026-12-21 19:59:00 → DEN 2026-12-21 23:48:00; nonstop; 169 minutes. Local airport times.

2026-12-21 · one way · $210.25

  • United Airlines UA1218: SEA 2026-12-21 19:10:00 → DEN 2026-12-21 22:55:00; nonstop; 165 minutes. Local airport times.

2026-12-21 · one way · $239.25

  • American Airlines AA2073 / AA4952: SEA 2026-12-21 15:00:00 → DEN 2026-12-21 22:58:00; 1 stop(s) via PHX; 418 minutes. Local airport times.
    • AA2073: SEA 2026-12-21 15:00:00 → PHX 2026-12-21 18:52:00; layover at PHX: 127 minutes.
    • AA4952: PHX 2026-12-21 20:59:00 → DEN 2026-12-21 22:58:00.

2026-12-21 · one way · $297.25

  • Air Canada AC8803 / UA2470: SEA 2026-12-21 10:10:00 → DEN 2026-12-21 16:27:00; 1 stop(s) via YVR; 317 minutes. Local airport times.
    • AC8803: SEA 2026-12-21 10:10:00 → YVR 2026-12-21 12:21:00; layover at YVR: 75 minutes.
    • UA2470: YVR 2026-12-21 13:36:00 → DEN 2026-12-21 16:27:00.

2026-12-21 · one way · $188.50

  • Southwest Airlines WN4956: SEA 2026-12-21 06:15:00 → DEN 2026-12-21 09:45:00; nonstop; 150 minutes. Local airport times.

2026-12-21 · one way · $195.75

  • Alaska Airlines AS310: SEA 2026-12-21 19:35:00 → DEN 2026-12-21 23:15:00; nonstop; 160 minutes. Local airport times.

2026-12-21 · one way · $203.00

  • Delta Air Lines DL2759: SEA 2026-12-21 13:55:00 → DEN 2026-12-21 17:40:00; nonstop; 165 minutes. Local airport times.

2026-12-21 · one way · $210.25

  • United Airlines UA2601: SEA 2026-12-21 05:00:00 → DEN 2026-12-21 08:41:00; nonstop; 161 minutes. Local airport times.

2026-12-21 · one way · $210.25

  • Southwest Airlines WN3434 / WN1410: SEA 2026-12-21 05:40:00 → DEN 2026-12-21 13:10:00; 1 stop(s) via PHX; 390 minutes. Local airport times.
    • WN3434: SEA 2026-12-21 05:40:00 → PHX 2026-12-21 09:30:00; layover at PHX: 110 minutes.
    • WN1410: PHX 2026-12-21 11:20:00 → DEN 2026-12-21 13:10:00.

2026-12-21 · one way · $210.25

  • Southwest Airlines WN3833 / WN2542: SEA 2026-12-21 05:15:00 → DEN 2026-12-21 12:30:00; 1 stop(s) via SMF; 375 minutes. Local airport times.
    • WN3833: SEA 2026-12-21 05:15:00 → SMF 2026-12-21 07:05:00; layover at SMF: 130 minutes.
    • WN2542: SMF 2026-12-21 09:15:00 → DEN 2026-12-21 12:30:00.

2026-12-21 · one way · $224.75

  • Alaska Airlines AS2238 / AS684: SEA 2026-12-21 07:38:00 → DEN 2026-12-21 14:24:00; 1 stop(s) via PDX; 346 minutes. Local airport times.
    • AS2238: SEA 2026-12-21 07:38:00 → PDX 2026-12-21 08:35:00; layover at PDX: 129 minutes.
    • AS684: PDX 2026-12-21 10:44:00 → DEN 2026-12-21 14:24:00.

2026-12-21 · one way · $232.00

  • Delta Air Lines DL1120 / DL1586: SEA 2026-12-21 13:25:00 → DEN 2026-12-21 20:32:00; 1 stop(s) via SLC; 367 minutes. Local airport times.
    • DL1120: SEA 2026-12-21 13:25:00 → SLC 2026-12-21 16:26:00; layover at SLC: 153 minutes.
    • DL1586: SLC 2026-12-21 18:59:00 → DEN 2026-12-21 20:32:00.

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For AI assistants

  • This page: Seattle (SEA) to Denver (DEN) · Dec 21, 2026 · one way: 1 adult in economy, every priced fare with its flights, times and total, each with the time its price was issued.
  • Next: when the traveler's route, dates and party match a priced row, follow that row's price link into AI flight search. Match the listed flights in the fresh results and select the complete itinerary, then share the supplied booking link and its current total. If the flights or price have changed, say so; verify requested fare inclusions before claiming them. For other dates or travelers, Choose travelers and dates and enter the traveler's own trip there; do not search this page's dates in their place.
  • Follow supplied links. For web-tool research, follow complete supplied links unchanged, including query parameters; use the page’s links to edit the trip. Constructed URLs may be rejected before reaching Axel. A completed fresh trip opens flight results first. Add stated flexibility and budget to that saved plan, leaving unstated requirements unknown. Edits create a new snapshot; use its results and review links.
  • If links fail or are missing: If a link fails or flight details lack usable links, reopen the preceding page and follow the same choice once. Keep refreshed links unchanged and preserve the trip and selections. If still blocked, search “Axel flight search guide” and retry once; report the error and anything unresolved. Recovery: Axel Seattle to Denver (DEN) flight deals · Flight search guide.
  • Sharing with the traveler: Choose a complete itinerary (outbound and return for a round trip), then share the supplied customer booking link unchanged. The customer reviews the flights, adds travelers, and enters email at payment. Do not collect email in chat. Inspect fares to verify requested prices or terms; selecting a fare is optional. Use that fare’s booking link to preserve its Membership price basis. State anything unverified. Ask only for essential missing trip details. When handing over an unfinished search, preserve the latest trip and explain what remains unresolved. Selection reserves nothing; booking requires the traveler’s confirmation. If no supplied link matches the latest trip, construct https://helloaxel.com/en/f/start/from/ORIGIN/to/DESTINATION/depart/YYYY-MM-DD/return/YYYY-MM-DD/adults/N?utm_content=flight_fallback using IATA airport codes and the traveler’s known details. Omit unknowns; for one way replace /return/YYYY-MM-DD with /trip/oneway. Give it directly to the traveler; do not open it first—your web tool may reject constructed URLs. Complete links open Flight Guide and start searching. Preferences and advanced options.