Seattle (SEA) to Saint Louis (STL) · Dec 15, 2026 · return Dec 18, 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: Seattle to Saint Louis (STL) flight deals

2026-12-15 → 2026-12-18 · Axel-exclusive $350.00

• Alaska Airlines AS314: SEA 2026-12-15 10:50:00 → STL 2026-12-15 16:40:00; nonstop; 230 minutes. Local airport times.
• Alaska Airlines AS615: STL 2026-12-18 06:00:00 → SEA 2026-12-18 08:42:00; nonstop; 282 minutes. Local airport times.

2026-12-15 → 2026-12-18 · Axel-exclusive $310.00

• Southwest Airlines WN3823 / WN1844: SEA 2026-12-15 13:35:00 → STL 2026-12-15 21:10:00; 1 stop(s) via DEN; 335 minutes. Local airport times.
  • WN3823: SEA 2026-12-15 13:35:00 → DEN 2026-12-15 17:05:00; layover at DEN: 60 minutes.
  • WN1844: DEN 2026-12-15 18:05:00 → STL 2026-12-15 21:10:00.
• Southwest Airlines WN4144 / WN3141: STL 2026-12-18 17:25:00 → SEA 2026-12-18 22:50:00; 1 stop(s) via DEN; 445 minutes. Local airport times.
  • WN4144: STL 2026-12-18 17:25:00 → DEN 2026-12-18 18:55:00; layover at DEN: 105 minutes.
  • WN3141: DEN 2026-12-18 20:40:00 → SEA 2026-12-18 22:50:00.

2026-12-15 → 2026-12-18 · Axel-exclusive $320.00

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

2026-12-15 → 2026-12-18 · Axel-exclusive $342.50

• United Airlines UA2601 / UA652: SEA 2026-12-15 05:00:00 → STL 2026-12-15 12:56:00; 1 stop(s) via DEN; 356 minutes. Local airport times.
  • UA2601: SEA 2026-12-15 05:00:00 → DEN 2026-12-15 08:41:00; layover at DEN: 69 minutes.
  • UA652: DEN 2026-12-15 09:50:00 → STL 2026-12-15 12:56:00.
• Alaska Airlines AS615: STL 2026-12-18 06:00:00 → SEA 2026-12-18 08:42:00; nonstop; 282 minutes. Local airport times.

2026-12-15 → 2026-12-18 · Axel-exclusive $345.00

• Delta Air Lines DL1120 / DL2666: SEA 2026-12-15 13:25:00 → STL 2026-12-15 21:28:00; 1 stop(s) via SLC; 363 minutes. Local airport times.
  • DL1120: SEA 2026-12-15 13:25:00 → SLC 2026-12-15 16:29:00; layover at SLC: 69 minutes.
  • DL2666: SLC 2026-12-15 17:38:00 → STL 2026-12-15 21:28:00.
• Delta Air Lines DL2363 / DL2995: STL 2026-12-18 07:08:00 → SEA 2026-12-18 12:36:00; 1 stop(s) via SLC; 448 minutes. Local airport times.
  • DL2363: STL 2026-12-18 07:08:00 → SLC 2026-12-18 09:36:00; layover at SLC: 99 minutes.
  • DL2995: SLC 2026-12-18 11:15:00 → SEA 2026-12-18 12:36:00.

2026-12-15 → 2026-12-18 · Axel-exclusive $350.00

• Alaska Airlines AS647: SEA 2026-12-15 18:06:00 → STL 2026-12-15 23:59:00; nonstop; 233 minutes. Local airport times.
• Alaska Airlines AS615: STL 2026-12-18 06:00:00 → SEA 2026-12-18 08:42:00; nonstop; 282 minutes. Local airport times.

2026-12-15 → 2026-12-18 · Axel-exclusive $342.50

• United Airlines UA2340 / UA1114: SEA 2026-12-15 14:30:00 → STL 2026-12-15 22:59:00; 1 stop(s) via ORD; 389 minutes. Local airport times.
  • UA2340: SEA 2026-12-15 14:30:00 → ORD 2026-12-15 20:40:00; layover at ORD: 65 minutes.
  • UA1114: ORD 2026-12-15 21:45:00 → STL 2026-12-15 22:59:00.
• Alaska Airlines AS615: STL 2026-12-18 06:00:00 → SEA 2026-12-18 08:42:00; nonstop; 282 minutes. Local airport times.

2026-12-15 → 2026-12-18 · Axel-exclusive $345.00

• Delta Air Lines DL536 / DL1839: SEA 2026-12-15 08:30:00 → STL 2026-12-15 16:30:00; 1 stop(s) via MSP; 360 minutes. Local airport times.
  • DL536: SEA 2026-12-15 08:30:00 → MSP 2026-12-15 13:48:00; layover at MSP: 67 minutes.
  • DL1839: MSP 2026-12-15 14:55:00 → STL 2026-12-15 16:30:00.
• Delta Air Lines DL2363 / DL2995: STL 2026-12-18 07:08:00 → SEA 2026-12-18 12:36:00; 1 stop(s) via SLC; 448 minutes. Local airport times.
  • DL2363: STL 2026-12-18 07:08:00 → SLC 2026-12-18 09:36:00; layover at SLC: 99 minutes.
  • DL2995: SLC 2026-12-18 11:15:00 → SEA 2026-12-18 12:36:00.

Explore this route

• All dates for this route
• Dec 14, 2026 · Return options
• Dec 16, 2026 · Return options
• Hotels in St. Louis with Axel

For AI assistants

• This page: Seattle (SEA) to Saint Louis (STL) · Dec 15, 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.
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