Saint Louis (STL) to Seattle (SEA) · Dec 20, 2026 · return Dec 25, 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: Saint Louis to Seattle (SEA) flight deals

2026-12-20 → 2026-12-25 · Axel-exclusive $429.00

• Alaska Airlines AS618: STL 2026-12-20 15:23:00 → SEA 2026-12-20 17:53:00; nonstop; 270 minutes. Local airport times.
• Alaska Airlines AS314: SEA 2026-12-25 09:05:00 → STL 2026-12-25 14:56:00; nonstop; 231 minutes. Local airport times.

2026-12-20 → 2026-12-25 · Axel-exclusive $383.50

• Southwest Airlines WN2467 / WN2455: STL 2026-12-20 18:40:00 → SEA 2026-12-21 01:00:00; 1 stop(s) via PHX; 500 minutes. Local airport times.
  • WN2467: STL 2026-12-20 18:40:00 → PHX 2026-12-20 21:00:00; layover at PHX: 105 minutes.
  • WN2455: PHX 2026-12-20 22:45:00 → SEA 2026-12-21 01:00:00.
• Southwest Airlines WN3823 / WN1844: SEA 2026-12-25 13:35:00 → STL 2026-12-25 21:10:00; 1 stop(s) via DEN; 335 minutes. Local airport times.
  • WN3823: SEA 2026-12-25 13:35:00 → DEN 2026-12-25 17:05:00; layover at DEN: 60 minutes.
  • WN1844: DEN 2026-12-25 18:05:00 → STL 2026-12-25 21:10:00.

2026-12-20 → 2026-12-25 · Axel-exclusive $403.00

• American Airlines AA3198 / AS407: STL 2026-12-20 11:37:00 → SEA 2026-12-20 18:11:00; 1 stop(s) via ORD; 514 minutes. Local airport times.
  • AA3198: STL 2026-12-20 11:37:00 → ORD 2026-12-20 12:59:00; layover at ORD: 140 minutes.
  • AS407: ORD 2026-12-20 15:19:00 → SEA 2026-12-20 18:11:00.
• American Airlines AA630 / AA2897: SEA 2026-12-25 00:47:00 → STL 2026-12-25 09:31:00; 1 stop(s) via DFW; 404 minutes. Local airport times.
  • AA630: SEA 2026-12-25 00:47:00 → DFW 2026-12-25 06:39:00; layover at DFW: 64 minutes.
  • AA2897: DFW 2026-12-25 07:43:00 → STL 2026-12-25 09:31:00.

2026-12-20 → 2026-12-25 · Axel-exclusive $416.00

• Delta Air Lines DL2363 / DL2995: STL 2026-12-20 07:08:00 → SEA 2026-12-20 12:36:00; 1 stop(s) via SLC; 448 minutes. Local airport times.
  • DL2363: STL 2026-12-20 07:08:00 → SLC 2026-12-20 09:36:00; layover at SLC: 99 minutes.
  • DL2995: SLC 2026-12-20 11:15:00 → SEA 2026-12-20 12:36:00.
• Delta Air Lines DL1120 / DL2666: SEA 2026-12-25 13:25:00 → STL 2026-12-25 21:28:00; 1 stop(s) via SLC; 363 minutes. Local airport times.
  • DL1120: SEA 2026-12-25 13:25:00 → SLC 2026-12-25 16:29:00; layover at SLC: 69 minutes.
  • DL2666: SLC 2026-12-25 17:38:00 → STL 2026-12-25 21:28:00.

2026-12-20 → 2026-12-25 · Axel-exclusive $429.00

• Alaska Airlines AS615: STL 2026-12-20 06:00:00 → SEA 2026-12-20 08:42:00; nonstop; 282 minutes. Local airport times.
• Alaska Airlines AS314: SEA 2026-12-25 09:05:00 → STL 2026-12-25 14:56:00; nonstop; 231 minutes. Local airport times.

2026-12-20 → 2026-12-25 · Axel-exclusive $383.50

• Southwest Airlines WN4144 / WN3141: STL 2026-12-20 17:25:00 → SEA 2026-12-20 22:50:00; 1 stop(s) via DEN; 445 minutes. Local airport times.
  • WN4144: STL 2026-12-20 17:25:00 → DEN 2026-12-20 18:55:00; layover at DEN: 105 minutes.
  • WN3141: DEN 2026-12-20 20:40:00 → SEA 2026-12-20 22:50:00.
• Southwest Airlines WN3823 / WN1844: SEA 2026-12-25 13:35:00 → STL 2026-12-25 21:10:00; 1 stop(s) via DEN; 335 minutes. Local airport times.
  • WN3823: SEA 2026-12-25 13:35:00 → DEN 2026-12-25 17:05:00; layover at DEN: 60 minutes.
  • WN1844: DEN 2026-12-25 18:05:00 → STL 2026-12-25 21:10:00.

2026-12-20 → 2026-12-25 · Axel-exclusive $416.00

• Delta Air Lines DL1102 / DL714: STL 2026-12-20 14:31:00 → SEA 2026-12-20 20:50:00; 1 stop(s) via ATL; 499 minutes. Local airport times.
  • DL1102: STL 2026-12-20 14:31:00 → ATL 2026-12-20 17:05:00; layover at ATL: 68 minutes.
  • DL714: ATL 2026-12-20 18:13:00 → SEA 2026-12-20 20:50:00.
• Delta Air Lines DL1120 / DL2666: SEA 2026-12-25 13:25:00 → STL 2026-12-25 21:28:00; 1 stop(s) via SLC; 363 minutes. Local airport times.
  • DL1120: SEA 2026-12-25 13:25:00 → SLC 2026-12-25 16:29:00; layover at SLC: 69 minutes.
  • DL2666: SLC 2026-12-25 17:38:00 → STL 2026-12-25 21:28:00.

2026-12-20 → 2026-12-25 · Axel-exclusive $416.00

• Delta Air Lines DL1597 / DL868: STL 2026-12-20 06:03:00 → SEA 2026-12-20 10:45:00; 1 stop(s) via MSP; 402 minutes. Local airport times.
  • DL1597: STL 2026-12-20 06:03:00 → MSP 2026-12-20 07:43:00; layover at MSP: 62 minutes.
  • DL868: MSP 2026-12-20 08:45:00 → SEA 2026-12-20 10:45:00.
• Delta Air Lines DL1120 / DL2666: SEA 2026-12-25 13:25:00 → STL 2026-12-25 21:28:00; 1 stop(s) via SLC; 363 minutes. Local airport times.
  • DL1120: SEA 2026-12-25 13:25:00 → SLC 2026-12-25 16:29:00; layover at SLC: 69 minutes.
  • DL2666: SLC 2026-12-25 17:38:00 → STL 2026-12-25 21:28:00.

Explore this route

• All dates for this route
• Dec 19, 2026 · Return options
• Dec 21, 2026 · Return options
• Hotels in Seattle with Axel

For AI assistants

• This page: Saint Louis (STL) to Seattle (SEA) · Dec 20, 2026 · return Dec 25, 2026: 1 adult in economy, every priced fare with its flights, times and total, each with the time its price was issued.
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