Denver (DEN) to Seattle (SEA) · Dec 19, 2026 · return Dec 21, 2026

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

See flights for these dates: each price link opens AI flight search for that row's exact dates and travelers. Select the complete itinerary there.

Route overview: Denver to Seattle (SEA) flight deals

2026-12-19 → 2026-12-21 · Axel-exclusive $231.00

• Frontier Airlines F94545: DEN 2026-12-19 13:32:00 → SEA 2026-12-19 15:43:00; nonstop; 191 minutes. Local airport times.
• Frontier Airlines F91916: SEA 2026-12-21 13:37:00 → DEN 2026-12-21 17:26:00; nonstop; 169 minutes. Local airport times.

2026-12-19 → 2026-12-21 · Axel-exclusive $378.00

• Southwest Airlines WN2174: DEN 2026-12-19 14:45:00 → SEA 2026-12-19 16:50:00; nonstop; 185 minutes. Local airport times.
• Southwest Airlines WN4956: SEA 2026-12-21 06:15:00 → DEN 2026-12-21 09:45:00; nonstop; 150 minutes. Local airport times.

2026-12-19 → 2026-12-21 · Axel-exclusive $392.00

• Alaska Airlines AS309: DEN 2026-12-19 21:42:00 → SEA 2026-12-19 23:49:00; nonstop; 187 minutes. Local airport times.
• Alaska Airlines AS535: SEA 2026-12-21 10:09:00 → DEN 2026-12-21 13:53:00; nonstop; 164 minutes. Local airport times.

2026-12-19 → 2026-12-21 · Axel-exclusive $406.00

• Delta Air Lines DL1731: DEN 2026-12-19 06:05:00 → SEA 2026-12-19 08:23:00; nonstop; 198 minutes. Local airport times.
• Delta Air Lines DL1358: SEA 2026-12-21 08:30:00 → DEN 2026-12-21 12:22:00; nonstop; 172 minutes. Local airport times.

2026-12-19 → 2026-12-21 · Axel-exclusive $406.00

• United Airlines UA310: DEN 2026-12-19 11:45:00 → SEA 2026-12-19 13:49:00; nonstop; 184 minutes. Local airport times.
• United Airlines UA1218: SEA 2026-12-21 19:10:00 → DEN 2026-12-21 22:55:00; nonstop; 165 minutes. Local airport times.

2026-12-19 → 2026-12-21 · Axel-exclusive $553.00

• Air Canada AC575 / AC8804: DEN 2026-12-19 08:15:00 → SEA 2026-12-19 14:32:00; 1 stop(s) via YVR; 437 minutes. Local airport times.
  • AC575: DEN 2026-12-19 08:15:00 → YVR 2026-12-19 11:25:00; layover at YVR: 185 minutes.
  • AC8804: YVR 2026-12-19 14:30:00 → SEA 2026-12-19 14:32:00.
• 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.

2026-12-19 → 2026-12-21 · Axel-exclusive $231.00

• Frontier Airlines F9605: DEN 2026-12-19 10:08:00 → SEA 2026-12-19 12:22:00; nonstop; 194 minutes. Local airport times.
• Frontier Airlines F91916: SEA 2026-12-21 13:37:00 → DEN 2026-12-21 17:26:00; nonstop; 169 minutes. Local airport times.

2026-12-19 → 2026-12-21 · Axel-exclusive $378.00

• Southwest Airlines WN3141: DEN 2026-12-19 20:55:00 → SEA 2026-12-19 23:05:00; nonstop; 190 minutes. Local airport times.
• Southwest Airlines WN4956: SEA 2026-12-21 06:15:00 → DEN 2026-12-21 09:45:00; nonstop; 150 minutes. Local airport times.

2026-12-19 → 2026-12-21 · Axel-exclusive $392.00

• Alaska Airlines AS317: DEN 2026-12-19 06:00:00 → SEA 2026-12-19 08:10:00; nonstop; 190 minutes. Local airport times.
• Alaska Airlines AS535: SEA 2026-12-21 10:09:00 → DEN 2026-12-21 13:53:00; nonstop; 164 minutes. Local airport times.

2026-12-19 → 2026-12-21 · Axel-exclusive $406.00

• Delta Air Lines DL2543: DEN 2026-12-19 18:33:00 → SEA 2026-12-19 20:40:00; nonstop; 187 minutes. Local airport times.
• Delta Air Lines DL1358: SEA 2026-12-21 08:30:00 → DEN 2026-12-21 12:22:00; nonstop; 172 minutes. Local airport times.

2026-12-19 → 2026-12-21 · Axel-exclusive $406.00

• United Airlines UA2013: DEN 2026-12-19 16:02:00 → SEA 2026-12-19 18:04:00; nonstop; 182 minutes. Local airport times.
• United Airlines UA1218: SEA 2026-12-21 19:10:00 → DEN 2026-12-21 22:55:00; nonstop; 165 minutes. Local airport times.

2026-12-19 → 2026-12-21 · Axel-exclusive $255.50

• Frontier Airlines F92015 / F92407: DEN 2026-12-19 06:25:00 → SEA 2026-12-19 12:27:00; 1 stop(s) via LAS; 422 minutes. Local airport times.
  • F92015: DEN 2026-12-19 06:25:00 → LAS 2026-12-19 07:37:00; layover at LAS: 112 minutes.
  • F92407: LAS 2026-12-19 09:29:00 → SEA 2026-12-19 12:27:00.
• Frontier Airlines F91916: SEA 2026-12-21 13:37:00 → DEN 2026-12-21 17:26:00; nonstop; 169 minutes. Local airport times.

2026-12-19 → 2026-12-21 · Axel-exclusive $399.00

• Southwest Airlines WN3148 / WN1586: DEN 2026-12-19 13:55:00 → SEA 2026-12-19 18:40:00; 1 stop(s) via SMF; 345 minutes. Local airport times.
  • WN3148: DEN 2026-12-19 13:55:00 → SMF 2026-12-19 15:30:00; layover at SMF: 70 minutes.
  • WN1586: SMF 2026-12-19 16:40:00 → SEA 2026-12-19 18:40:00.
• Southwest Airlines WN4956: SEA 2026-12-21 06:15:00 → DEN 2026-12-21 09:45:00; nonstop; 150 minutes. Local airport times.

2026-12-19 → 2026-12-21 · Axel-exclusive $399.00

• Southwest Airlines WN1660 / WN948: DEN 2026-12-19 07:30:00 → SEA 2026-12-19 13:00:00; 1 stop(s) via LAS; 390 minutes. Local airport times.
  • WN1660: DEN 2026-12-19 07:30:00 → LAS 2026-12-19 08:30:00; layover at LAS: 90 minutes.
  • WN948: LAS 2026-12-19 10:00:00 → SEA 2026-12-19 13:00:00.
• Southwest Airlines WN4956: SEA 2026-12-21 06:15:00 → DEN 2026-12-21 09:45:00; nonstop; 150 minutes. Local airport times.

2026-12-19 → 2026-12-21 · Axel-exclusive $413.00

• Alaska Airlines AS686 / AS3217: DEN 2026-12-19 07:40:00 → SEA 2026-12-19 12:09:00; 1 stop(s) via PDX; 329 minutes. Local airport times.
  • AS686: DEN 2026-12-19 07:40:00 → PDX 2026-12-19 09:39:00; layover at PDX: 75 minutes.
  • AS3217: PDX 2026-12-19 10:54:00 → SEA 2026-12-19 12:09:00.
• Alaska Airlines AS535: SEA 2026-12-21 10:09:00 → DEN 2026-12-21 13:53:00; nonstop; 164 minutes. Local airport times.

2026-12-19 → 2026-12-21 · Axel-exclusive $434.00

• United Airlines UA1086 / AC8810: DEN 2026-12-19 15:53:00 → SEA 2026-12-19 21:57:00; 1 stop(s) via YVR; 424 minutes. Local airport times.
  • UA1086: DEN 2026-12-19 15:53:00 → YVR 2026-12-19 19:04:00; layover at YVR: 166 minutes.
  • AC8810: YVR 2026-12-19 21:50:00 → SEA 2026-12-19 21:57:00.
• United Airlines UA1218: SEA 2026-12-21 19:10:00 → DEN 2026-12-21 22:55:00; nonstop; 165 minutes. Local airport times.

Explore this route

• All dates for this route
• Dec 18, 2026 · Return options
• Dec 20, 2026 · Return options
• Hotels in Seattle with Axel

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