Seattle (SEA) to Saint Louis (STL) · Dec 19, 2026 · one way

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

2026-12-19 · one way · Axel-exclusive $252.00

• Alaska Airlines AS647: SEA 2026-12-19 18:05:00 → STL 2026-12-19 23:59:00; nonstop; 234 minutes. Local airport times.

2026-12-19 · one way · Axel-exclusive $224.00

• Southwest Airlines WN3823 / WN1844: SEA 2026-12-19 13:35:00 → STL 2026-12-19 21:10:00; 1 stop(s) via DEN; 335 minutes. Local airport times.
  • WN3823: SEA 2026-12-19 13:35:00 → DEN 2026-12-19 17:05:00; layover at DEN: 60 minutes.
  • WN1844: DEN 2026-12-19 18:05:00 → STL 2026-12-19 21:10:00.

2026-12-19 · one way · Axel-exclusive $231.00

• American Airlines AA630 / AA2897: SEA 2026-12-19 00:47:00 → STL 2026-12-19 09:31:00; 1 stop(s) via DFW; 404 minutes. Local airport times.
  • AA630: SEA 2026-12-19 00:47:00 → DFW 2026-12-19 06:39:00; layover at DFW: 64 minutes.
  • AA2897: DFW 2026-12-19 07:43:00 → STL 2026-12-19 09:31:00.

2026-12-19 · one way · Axel-exclusive $245.00

• United Airlines UA2340 / UA1114: SEA 2026-12-19 14:30:00 → STL 2026-12-19 22:59:00; 1 stop(s) via ORD; 389 minutes. Local airport times.
  • UA2340: SEA 2026-12-19 14:30:00 → ORD 2026-12-19 20:40:00; layover at ORD: 65 minutes.
  • UA1114: ORD 2026-12-19 21:45:00 → STL 2026-12-19 22:59:00.

2026-12-19 · one way · Axel-exclusive $252.00

• Delta Air Lines DL536 / DL1839: SEA 2026-12-19 08:30:00 → STL 2026-12-19 16:30:00; 1 stop(s) via MSP; 360 minutes. Local airport times.
  • DL536: SEA 2026-12-19 08:30:00 → MSP 2026-12-19 13:48:00; layover at MSP: 67 minutes.
  • DL1839: MSP 2026-12-19 14:55:00 → STL 2026-12-19 16:30:00.

2026-12-19 · one way · Axel-exclusive $252.00

• Alaska Airlines AS618: SEA 2026-12-19 09:41:00 → STL 2026-12-19 15:34:00; nonstop; 233 minutes. Local airport times.

2026-12-19 · one way · Axel-exclusive $245.00

• United Airlines UA2601 / UA652: SEA 2026-12-19 05:00:00 → STL 2026-12-19 12:56:00; 1 stop(s) via DEN; 356 minutes. Local airport times.
  • UA2601: SEA 2026-12-19 05:00:00 → DEN 2026-12-19 08:41:00; layover at DEN: 69 minutes.
  • UA652: DEN 2026-12-19 09:50:00 → STL 2026-12-19 12:56:00.

2026-12-19 · one way · Axel-exclusive $252.00

• Delta Air Lines DL1120 / DL2666: SEA 2026-12-19 13:25:00 → STL 2026-12-19 21:28:00; 1 stop(s) via SLC; 363 minutes. Local airport times.
  • DL1120: SEA 2026-12-19 13:25:00 → SLC 2026-12-19 16:29:00; layover at SLC: 69 minutes.
  • DL2666: SLC 2026-12-19 17:38:00 → STL 2026-12-19 21:28:00.

Travelers: prices on this page are totals for 1 adult. For a different party, open this trip for 2 adults · 3 adults · 4 adults · 2 adults + 1 child · 2 adults + 2 children; each link opens AI flight search for these dates and those travelers, and the customer link to share comes from those results.

Explore this route

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

For AI assistants

• This page: Seattle (SEA) to Saint Louis (STL) · Dec 19, 2026 · one way: 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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