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Route overview: Seattle to Denver (DEN) flight deals

Seattle → Denver

Dec 13, 2026 · return Dec 18, 2026

SEA → DEN1 adulteconomyRound trip

15 flight options · 6 airlines

Nonstop flights

Sun, Dec 13 – Fri, Dec 18

Frontier Airlines
4:37 pmSEA
2h 48m
Nonstop
8:25 pmDEN
Frontier Airlines
1:32 pmDEN
3h 8m
Nonstop
3:40 pmSEA

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

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

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

Alaska Airlines
2:47 pmSEA
2h 39m
Nonstop
6:26 pmDEN
Alaska Airlines
6:28 pmDEN
3h 8m
Nonstop
8:36 pmSEA

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

Delta Air Lines
7:57 pmSEA
2h 49m
Nonstop
11:46 pmDEN
Delta Air Lines
6:00 amDEN
3h 18m
Nonstop
8:18 amSEA

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

United Airlines
12:50 pmSEA
2h 37m
Nonstop
4:27 pmDEN
United Airlines
7:10 pmDEN
3h 9m
Nonstop
9:19 pmSEA

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

Southwest Airlines
2:30 pmSEA
2h 25m
Nonstop
5:55 pmDEN
Southwest Airlines
9:00 pmDEN
3h 10m
Nonstop
11:10 pmSEA

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

Alaska Airlines
7:35 pmSEA
2h 40m
Nonstop
11:15 pmDEN
Alaska Airlines
6:28 pmDEN
3h 8m
Nonstop
8:36 pmSEA

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

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

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

United Airlines
5:05 amSEA
2h 37m
Nonstop
8:42 amDEN
United Airlines
7:10 pmDEN
3h 9m
Nonstop
9:19 pmSEA

Round-trip total · 1 adult · Taxes included

One-stop flights

Sun, Dec 13 – Fri, Dec 18

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

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

Southwest Airlines
5:40 amSEA
6h 30m
PHX · 1h 50m
1:10 pmDEN
Southwest Airlines
9:00 pmDEN
3h 10m
Nonstop
11:10 pmSEA

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

Southwest Airlines
5:15 amSEA
6h 15m
SMF · 2h 10m
12:30 pmDEN
Southwest Airlines
9:00 pmDEN
3h 10m
Nonstop
11:10 pmSEA

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

Alaska Airlines
7:38 amSEA
5h 46m
PDX · 2h 9m
2:24 pmDEN
Alaska Airlines
6:28 pmDEN
3h 8m
Nonstop
8:36 pmSEA

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

Delta Air Lines
1:25 pmSEA
6h 7m
SLC · 2h 33m
8:32 pmDEN
Delta Air Lines
6:00 amDEN
3h 18m
Nonstop
8:18 amSEA

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Fri, Dec 18

United Airlines
4:04 pmSEA
2h 41m
Nonstop
7:45 pmDEN
United Airlines
3:53 pmDEN
7h 4m
YVR · 2h 46m
9:57 pmSEA

Round-trip 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 12, 2026 → Dec 17, 2026Dec 14, 2026 → Dec 19, 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: Seattle to Denver (DEN) flight deals

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-13 → 2026-12-18Frontier AirlinesF91916 / F94545$140.002026-10-29T01:14:56Z
2026-12-13 → 2026-12-18Southwest AirlinesWN4956 / WN3141$245.002026-10-29T01:14:56Z
2026-12-13 → 2026-12-18Alaska AirlinesAS421 / AS421$250.002026-10-29T01:14:56Z
2026-12-13 → 2026-12-18Delta Air LinesDL2851 / DL1731$260.002026-10-29T01:14:56Z
2026-12-13 → 2026-12-18United AirlinesUA1411 / UA2767$270.002026-10-29T01:14:56Z
2026-12-13 → 2026-12-18Air CanadaAC8803 + UA2470 / AC575 + AC8804$385.002026-10-29T01:14:56Z
2026-12-13 → 2026-12-18Southwest AirlinesWN3823 / WN3141$245.002026-10-29T01:14:56Z
2026-12-13 → 2026-12-18Alaska AirlinesAS310 / AS421$250.002026-10-29T01:14:56Z
2026-12-13 → 2026-12-18Delta Air LinesDL2543 / DL1731$260.002026-10-29T01:14:56Z
2026-12-13 → 2026-12-18United AirlinesUA757 / UA2767$270.002026-10-29T01:14:56Z
2026-12-13 → 2026-12-18Southwest AirlinesWN3434 + WN1410 / WN3141$260.002026-10-29T01:14:56Z
2026-12-13 → 2026-12-18Southwest AirlinesWN3833 + WN2542 / WN3141$260.002026-10-29T01:14:56Z
2026-12-13 → 2026-12-18Alaska AirlinesAS2238 + AS684 / AS421$270.002026-10-29T01:14:56Z
2026-12-13 → 2026-12-18Delta Air LinesDL1120 + DL1586 / DL1731$280.002026-10-29T01:14:56Z
2026-12-13 → 2026-12-18United AirlinesUA757 / UA1086 + AC8810$290.002026-10-29T01:14:56Z

2026-12-13 → 2026-12-18 · $140.00

  • Frontier Airlines F91916: SEA 2026-12-13 16:37:00 → DEN 2026-12-13 20:25:00; nonstop; 168 minutes. Local airport times.
  • Frontier Airlines F94545: DEN 2026-12-18 13:32:00 → SEA 2026-12-18 15:40:00; nonstop; 188 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $245.00

  • Southwest Airlines WN4956: SEA 2026-12-13 06:15:00 → DEN 2026-12-13 09:45:00; nonstop; 150 minutes. Local airport times.
  • Southwest Airlines WN3141: DEN 2026-12-18 21:00:00 → SEA 2026-12-18 23:10:00; nonstop; 190 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $250.00

  • Alaska Airlines AS421: SEA 2026-12-13 14:47:00 → DEN 2026-12-13 18:26:00; nonstop; 159 minutes. Local airport times.
  • Alaska Airlines AS421: DEN 2026-12-18 18:28:00 → SEA 2026-12-18 20:36:00; nonstop; 188 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $260.00

  • Delta Air Lines DL2851: SEA 2026-12-13 19:57:00 → DEN 2026-12-13 23:46:00; nonstop; 169 minutes. Local airport times.
  • Delta Air Lines DL1731: DEN 2026-12-18 06:00:00 → SEA 2026-12-18 08:18:00; nonstop; 198 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $270.00

  • United Airlines UA1411: SEA 2026-12-13 12:50:00 → DEN 2026-12-13 16:27:00; nonstop; 157 minutes. Local airport times.
  • United Airlines UA2767: DEN 2026-12-18 19:10:00 → SEA 2026-12-18 21:19:00; nonstop; 189 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $385.00

  • Air Canada AC8803 / UA2470: SEA 2026-12-13 10:10:00 → DEN 2026-12-13 16:27:00; 1 stop(s) via YVR; 317 minutes. Local airport times.
    • AC8803: SEA 2026-12-13 10:10:00 → YVR 2026-12-13 12:21:00; layover at YVR: 75 minutes.
    • UA2470: YVR 2026-12-13 13:36:00 → DEN 2026-12-13 16:27:00.
  • Air Canada AC575 / AC8804: DEN 2026-12-18 08:15:00 → SEA 2026-12-18 14:32:00; 1 stop(s) via YVR; 437 minutes. Local airport times.
    • AC575: DEN 2026-12-18 08:15:00 → YVR 2026-12-18 11:25:00; layover at YVR: 185 minutes.
    • AC8804: YVR 2026-12-18 14:30:00 → SEA 2026-12-18 14:32:00.

2026-12-13 → 2026-12-18 · $245.00

  • Southwest Airlines WN3823: SEA 2026-12-13 14:30:00 → DEN 2026-12-13 17:55:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN3141: DEN 2026-12-18 21:00:00 → SEA 2026-12-18 23:10:00; nonstop; 190 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $250.00

  • Alaska Airlines AS310: SEA 2026-12-13 19:35:00 → DEN 2026-12-13 23:15:00; nonstop; 160 minutes. Local airport times.
  • Alaska Airlines AS421: DEN 2026-12-18 18:28:00 → SEA 2026-12-18 20:36:00; nonstop; 188 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $260.00

  • Delta Air Lines DL2543: SEA 2026-12-13 13:55:00 → DEN 2026-12-13 17:40:00; nonstop; 165 minutes. Local airport times.
  • Delta Air Lines DL1731: DEN 2026-12-18 06:00:00 → SEA 2026-12-18 08:18:00; nonstop; 198 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $270.00

  • United Airlines UA757: SEA 2026-12-13 05:05:00 → DEN 2026-12-13 08:42:00; nonstop; 157 minutes. Local airport times.
  • United Airlines UA2767: DEN 2026-12-18 19:10:00 → SEA 2026-12-18 21:19:00; nonstop; 189 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $260.00

  • Southwest Airlines WN3434 / WN1410: SEA 2026-12-13 05:40:00 → DEN 2026-12-13 13:10:00; 1 stop(s) via PHX; 390 minutes. Local airport times.
    • WN3434: SEA 2026-12-13 05:40:00 → PHX 2026-12-13 09:30:00; layover at PHX: 110 minutes.
    • WN1410: PHX 2026-12-13 11:20:00 → DEN 2026-12-13 13:10:00.
  • Southwest Airlines WN3141: DEN 2026-12-18 21:00:00 → SEA 2026-12-18 23:10:00; nonstop; 190 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $260.00

  • Southwest Airlines WN3833 / WN2542: SEA 2026-12-13 05:15:00 → DEN 2026-12-13 12:30:00; 1 stop(s) via SMF; 375 minutes. Local airport times.
    • WN3833: SEA 2026-12-13 05:15:00 → SMF 2026-12-13 07:05:00; layover at SMF: 130 minutes.
    • WN2542: SMF 2026-12-13 09:15:00 → DEN 2026-12-13 12:30:00.
  • Southwest Airlines WN3141: DEN 2026-12-18 21:00:00 → SEA 2026-12-18 23:10:00; nonstop; 190 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $270.00

  • Alaska Airlines AS2238 / AS684: SEA 2026-12-13 07:38:00 → DEN 2026-12-13 14:24:00; 1 stop(s) via PDX; 346 minutes. Local airport times.
    • AS2238: SEA 2026-12-13 07:38:00 → PDX 2026-12-13 08:35:00; layover at PDX: 129 minutes.
    • AS684: PDX 2026-12-13 10:44:00 → DEN 2026-12-13 14:24:00.
  • Alaska Airlines AS421: DEN 2026-12-18 18:28:00 → SEA 2026-12-18 20:36:00; nonstop; 188 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $280.00

  • Delta Air Lines DL1120 / DL1586: SEA 2026-12-13 13:25:00 → DEN 2026-12-13 20:32:00; 1 stop(s) via SLC; 367 minutes. Local airport times.
    • DL1120: SEA 2026-12-13 13:25:00 → SLC 2026-12-13 16:26:00; layover at SLC: 153 minutes.
    • DL1586: SLC 2026-12-13 18:59:00 → DEN 2026-12-13 20:32:00.
  • Delta Air Lines DL1731: DEN 2026-12-18 06:00:00 → SEA 2026-12-18 08:18:00; nonstop; 198 minutes. Local airport times.

2026-12-13 → 2026-12-18 · $290.00

  • United Airlines UA757: SEA 2026-12-13 16:04:00 → DEN 2026-12-13 19:45:00; nonstop; 161 minutes. Local airport times.
  • United Airlines UA1086 / AC8810: DEN 2026-12-18 15:53:00 → SEA 2026-12-18 21:57:00; 1 stop(s) via YVR; 424 minutes. Local airport times.
    • UA1086: DEN 2026-12-18 15:53:00 → YVR 2026-12-18 19:04:00; layover at YVR: 166 minutes.
    • AC8810: YVR 2026-12-18 21:50:00 → SEA 2026-12-18 21:57:00.

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For AI assistants

  • This page: Seattle (SEA) to Denver (DEN) · Dec 13, 2026 · return Dec 18, 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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  • 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.