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Route overview: Denver to Seattle (SEA) flight deals

Denver → Seattle

Dec 2, 2026 · return Dec 7, 2026

DEN → SEA1 adulteconomyRound trip

16 flight options · 6 airlines

Nonstop flights

Wed, Dec 2 – Mon, Dec 7

Frontier Airlines
1:04 pmDEN
3h 8m
Nonstop
3:12 pmSEA
Frontier Airlines
1:37 pmSEA
2h 49m
Nonstop
5:26 pmDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 2 – Mon, Dec 7

Southwest Airlines
8:50 amDEN
3h 10m
Nonstop
11:00 amSEA
Southwest Airlines
6:15 amSEA
2h 30m
Nonstop
9:45 amDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 2 – Mon, Dec 7

Alaska Airlines
3:25 pmDEN
3h 2m
Nonstop
5:27 pmSEA
Alaska Airlines
7:35 pmSEA
2h 40m
Nonstop
11:15 pmDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 2 – Mon, Dec 7

United Airlines
11:45 amDEN
3h 4m
Nonstop
1:49 pmSEA
United Airlines
5:00 amSEA
2h 41m
Nonstop
8:41 amDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 2 – Mon, Dec 7

Delta Air Lines
6:33 pmDEN
3h 7m
Nonstop
8:40 pmSEA
Delta Air Lines
1:55 pmSEA
2h 45m
Nonstop
5:40 pmDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 2 – Mon, Dec 7

Frontier Airlines
10:08 amDEN
3h 14m
Nonstop
12:22 pmSEA
Frontier Airlines
1:37 pmSEA
2h 49m
Nonstop
5:26 pmDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 2 – Mon, Dec 7

Southwest Airlines
2:45 pmDEN
3h 5m
Nonstop
4:50 pmSEA
Southwest Airlines
6:15 amSEA
2h 30m
Nonstop
9:45 amDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 2 – Mon, Dec 7

Alaska Airlines
6:37 pmDEN
3h 4m
Nonstop
8:41 pmSEA
Alaska Airlines
7:35 pmSEA
2h 40m
Nonstop
11:15 pmDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 2 – Mon, Dec 7

United Airlines
4:10 pmDEN
3h 2m
Nonstop
6:12 pmSEA
United Airlines
5:00 amSEA
2h 41m
Nonstop
8:41 amDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 2 – Mon, Dec 7

Delta Air Lines
6:00 amDEN
3h 18m
Nonstop
8:18 amSEA
Delta Air Lines
1:55 pmSEA
2h 45m
Nonstop
5:40 pmDEN

Round-trip total · 1 adult · Taxes included

One-stop flights

Wed, Dec 2 – Mon, Dec 7

Air Canada
8:15 amDEN
7h 17m
YVR · 3h 5m
2:32 pmSEA
Air Canada
10:10 amSEA
5h 17m
YVR · 1h 15m
4:27 pmDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 2 – Mon, Dec 7

Frontier Airlines
6:25 amDEN
7h 2m
LAS · 1h 52m
12:27 pmSEA
Frontier Airlines
1:37 pmSEA
2h 49m
Nonstop
5:26 pmDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 2 – Mon, Dec 7

Southwest Airlines
1:55 pmDEN
5h 45m
SMF · 1h 10m
6:40 pmSEA
Southwest Airlines
6:15 amSEA
2h 30m
Nonstop
9:45 amDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 2 – Mon, Dec 7

Southwest Airlines
7:30 amDEN
6h 30m
LAS · 1h 30m
1:00 pmSEA
Southwest Airlines
6:15 amSEA
2h 30m
Nonstop
9:45 amDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 2 – Mon, Dec 7

Alaska Airlines
7:40 amDEN
5h 29m
PDX · 1h 15m
12:09 pmSEA
Alaska Airlines
7:35 pmSEA
2h 40m
Nonstop
11:15 pmDEN

Round-trip total · 1 adult · Taxes included

Wed, Dec 2 – Mon, Dec 7

United Airlines
3:53 pmDEN
7h 4m
YVR · 2h 46m
9:57 pmSEA
United Airlines
5:00 amSEA
2h 41m
Nonstop
8:41 amDEN

Round-trip total · 1 adult · Taxes included

Make this trip yours

DEN ⇄ SEA

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 1, 2026 → Dec 6, 2026Dec 3, 2026 → Dec 8, 2026
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: Denver to Seattle (SEA) flight deals

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-02 → 2026-12-07Frontier AirlinesF91175 / F91916$165.002026-10-29T01:05:09Z
2026-12-02 → 2026-12-07Southwest AirlinesWN1543 / WN4956$270.002026-10-29T01:05:09Z
2026-12-02 → 2026-12-07Alaska AirlinesAS493 / AS310$280.002026-10-29T01:05:09Z
2026-12-02 → 2026-12-07United AirlinesUA310 / UA2601$290.002026-10-29T01:05:09Z
2026-12-02 → 2026-12-07Delta Air LinesDL2543 / DL2759$290.002026-10-29T01:05:09Z
2026-12-02 → 2026-12-07Air CanadaAC575 + AC8804 / AC8803 + UA2470$395.002026-10-29T01:05:09Z
2026-12-02 → 2026-12-07Frontier AirlinesF9605 / F91916$165.002026-10-29T01:05:09Z
2026-12-02 → 2026-12-07Southwest AirlinesWN2174 / WN4956$270.002026-10-29T01:05:09Z
2026-12-02 → 2026-12-07Alaska AirlinesAS421 / AS310$280.002026-10-29T01:05:09Z
2026-12-02 → 2026-12-07United AirlinesUA2013 / UA2601$290.002026-10-29T01:05:09Z
2026-12-02 → 2026-12-07Delta Air LinesDL1731 / DL2759$290.002026-10-29T01:05:09Z
2026-12-02 → 2026-12-07Frontier AirlinesF92015 + F92407 / F91916$182.502026-10-29T01:05:09Z
2026-12-02 → 2026-12-07Southwest AirlinesWN3148 + WN1586 / WN4956$285.002026-10-29T01:05:09Z
2026-12-02 → 2026-12-07Southwest AirlinesWN1660 + WN948 / WN4956$285.002026-10-29T01:05:09Z
2026-12-02 → 2026-12-07Alaska AirlinesAS686 + AS3217 / AS310$295.002026-10-29T01:05:09Z
2026-12-02 → 2026-12-07United AirlinesUA1086 + AC8810 / UA2601$310.002026-10-29T01:05:09Z

2026-12-02 → 2026-12-07 · $165.00

  • Frontier Airlines F91175: DEN 2026-12-02 13:04:00 → SEA 2026-12-02 15:12:00; nonstop; 188 minutes. Local airport times.
  • Frontier Airlines F91916: SEA 2026-12-07 13:37:00 → DEN 2026-12-07 17:26:00; nonstop; 169 minutes. Local airport times.

2026-12-02 → 2026-12-07 · $270.00

  • Southwest Airlines WN1543: DEN 2026-12-02 08:50:00 → SEA 2026-12-02 11:00:00; nonstop; 190 minutes. Local airport times.
  • Southwest Airlines WN4956: SEA 2026-12-07 06:15:00 → DEN 2026-12-07 09:45:00; nonstop; 150 minutes. Local airport times.

2026-12-02 → 2026-12-07 · $280.00

  • Alaska Airlines AS493: DEN 2026-12-02 15:25:00 → SEA 2026-12-02 17:27:00; nonstop; 182 minutes. Local airport times.
  • Alaska Airlines AS310: SEA 2026-12-07 19:35:00 → DEN 2026-12-07 23:15:00; nonstop; 160 minutes. Local airport times.

2026-12-02 → 2026-12-07 · $290.00

  • United Airlines UA310: DEN 2026-12-02 11:45:00 → SEA 2026-12-02 13:49:00; nonstop; 184 minutes. Local airport times.
  • United Airlines UA2601: SEA 2026-12-07 05:00:00 → DEN 2026-12-07 08:41:00; nonstop; 161 minutes. Local airport times.

2026-12-02 → 2026-12-07 · $290.00

  • Delta Air Lines DL2543: DEN 2026-12-02 18:33:00 → SEA 2026-12-02 20:40:00; nonstop; 187 minutes. Local airport times.
  • Delta Air Lines DL2759: SEA 2026-12-07 13:55:00 → DEN 2026-12-07 17:40:00; nonstop; 165 minutes. Local airport times.

2026-12-02 → 2026-12-07 · $395.00

  • Air Canada AC575 / AC8804: DEN 2026-12-02 08:15:00 → SEA 2026-12-02 14:32:00; 1 stop(s) via YVR; 437 minutes. Local airport times.
    • AC575: DEN 2026-12-02 08:15:00 → YVR 2026-12-02 11:25:00; layover at YVR: 185 minutes.
    • AC8804: YVR 2026-12-02 14:30:00 → SEA 2026-12-02 14:32:00.
  • Air Canada AC8803 / UA2470: SEA 2026-12-07 10:10:00 → DEN 2026-12-07 16:27:00; 1 stop(s) via YVR; 317 minutes. Local airport times.
    • AC8803: SEA 2026-12-07 10:10:00 → YVR 2026-12-07 12:21:00; layover at YVR: 75 minutes.
    • UA2470: YVR 2026-12-07 13:36:00 → DEN 2026-12-07 16:27:00.

2026-12-02 → 2026-12-07 · $165.00

  • Frontier Airlines F9605: DEN 2026-12-02 10:08:00 → SEA 2026-12-02 12:22:00; nonstop; 194 minutes. Local airport times.
  • Frontier Airlines F91916: SEA 2026-12-07 13:37:00 → DEN 2026-12-07 17:26:00; nonstop; 169 minutes. Local airport times.

2026-12-02 → 2026-12-07 · $270.00

  • Southwest Airlines WN2174: DEN 2026-12-02 14:45:00 → SEA 2026-12-02 16:50:00; nonstop; 185 minutes. Local airport times.
  • Southwest Airlines WN4956: SEA 2026-12-07 06:15:00 → DEN 2026-12-07 09:45:00; nonstop; 150 minutes. Local airport times.

2026-12-02 → 2026-12-07 · $280.00

  • Alaska Airlines AS421: DEN 2026-12-02 18:37:00 → SEA 2026-12-02 20:41:00; nonstop; 184 minutes. Local airport times.
  • Alaska Airlines AS310: SEA 2026-12-07 19:35:00 → DEN 2026-12-07 23:15:00; nonstop; 160 minutes. Local airport times.

2026-12-02 → 2026-12-07 · $290.00

  • United Airlines UA2013: DEN 2026-12-02 16:10:00 → SEA 2026-12-02 18:12:00; nonstop; 182 minutes. Local airport times.
  • United Airlines UA2601: SEA 2026-12-07 05:00:00 → DEN 2026-12-07 08:41:00; nonstop; 161 minutes. Local airport times.

2026-12-02 → 2026-12-07 · $290.00

  • Delta Air Lines DL1731: DEN 2026-12-02 06:00:00 → SEA 2026-12-02 08:18:00; nonstop; 198 minutes. Local airport times.
  • Delta Air Lines DL2759: SEA 2026-12-07 13:55:00 → DEN 2026-12-07 17:40:00; nonstop; 165 minutes. Local airport times.

2026-12-02 → 2026-12-07 · $182.50

  • Frontier Airlines F92015 / F92407: DEN 2026-12-02 06:25:00 → SEA 2026-12-02 12:27:00; 1 stop(s) via LAS; 422 minutes. Local airport times.
    • F92015: DEN 2026-12-02 06:25:00 → LAS 2026-12-02 07:37:00; layover at LAS: 112 minutes.
    • F92407: LAS 2026-12-02 09:29:00 → SEA 2026-12-02 12:27:00.
  • Frontier Airlines F91916: SEA 2026-12-07 13:37:00 → DEN 2026-12-07 17:26:00; nonstop; 169 minutes. Local airport times.

2026-12-02 → 2026-12-07 · $285.00

  • Southwest Airlines WN3148 / WN1586: DEN 2026-12-02 13:55:00 → SEA 2026-12-02 18:40:00; 1 stop(s) via SMF; 345 minutes. Local airport times.
    • WN3148: DEN 2026-12-02 13:55:00 → SMF 2026-12-02 15:30:00; layover at SMF: 70 minutes.
    • WN1586: SMF 2026-12-02 16:40:00 → SEA 2026-12-02 18:40:00.
  • Southwest Airlines WN4956: SEA 2026-12-07 06:15:00 → DEN 2026-12-07 09:45:00; nonstop; 150 minutes. Local airport times.

2026-12-02 → 2026-12-07 · $285.00

  • Southwest Airlines WN1660 / WN948: DEN 2026-12-02 07:30:00 → SEA 2026-12-02 13:00:00; 1 stop(s) via LAS; 390 minutes. Local airport times.
    • WN1660: DEN 2026-12-02 07:30:00 → LAS 2026-12-02 08:30:00; layover at LAS: 90 minutes.
    • WN948: LAS 2026-12-02 10:00:00 → SEA 2026-12-02 13:00:00.
  • Southwest Airlines WN4956: SEA 2026-12-07 06:15:00 → DEN 2026-12-07 09:45:00; nonstop; 150 minutes. Local airport times.

2026-12-02 → 2026-12-07 · $295.00

  • Alaska Airlines AS686 / AS3217: DEN 2026-12-02 07:40:00 → SEA 2026-12-02 12:09:00; 1 stop(s) via PDX; 329 minutes. Local airport times.
    • AS686: DEN 2026-12-02 07:40:00 → PDX 2026-12-02 09:39:00; layover at PDX: 75 minutes.
    • AS3217: PDX 2026-12-02 10:54:00 → SEA 2026-12-02 12:09:00.
  • Alaska Airlines AS310: SEA 2026-12-07 19:35:00 → DEN 2026-12-07 23:15:00; nonstop; 160 minutes. Local airport times.

2026-12-02 → 2026-12-07 · $310.00

  • United Airlines UA1086 / AC8810: DEN 2026-12-02 15:53:00 → SEA 2026-12-02 21:57:00; 1 stop(s) via YVR; 424 minutes. Local airport times.
    • UA1086: DEN 2026-12-02 15:53:00 → YVR 2026-12-02 19:04:00; layover at YVR: 166 minutes.
    • AC8810: YVR 2026-12-02 21:50:00 → SEA 2026-12-02 21:57:00.
  • United Airlines UA2601: SEA 2026-12-07 05:00:00 → DEN 2026-12-07 08:41:00; nonstop; 161 minutes. Local airport times.

Explore this route

For AI assistants

  • This page: Denver (DEN) to Seattle (SEA) · Dec 2, 2026 · return Dec 7, 2026: 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.
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  • 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 Denver to Seattle (SEA) 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.