Seattle (SEA) to Saint Louis (STL), Dec 20–21, 2026: from $434 round trip

Seattle (SEA) to Saint Louis (STL), Dec 20–21, 2026: from $434 round trip on Axel, checked Nov 15, 2026. Lowest published fare: $434 round trip, Axel-exclusive, Southwest Airlines, 1 stop, Dec 20–21, 2026, 1 adult, economy, checked Nov 15, 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.

Hotels in St. Louis for these trips

Hotels: under a trip, hotels in St. Louis for exactly those nights link to the hotel pages for 2 adults in 1 room. When a price is shown, it is the nightly rate and the stay's total, from the lowest saved total among the shortlisted hotels in that star tier for those dates.

• Hotels in St. Louis for these nights (Dec 20–21, 2026 · 1 night · 2 adults, 1 room): 3★ Clayton Plaza Hotel & Extended Stay, $68 a night · 4★ Hilton St. Louis at the Ballpark, $102 a night · 5★ Four Seasons Hotel St Louis, $422 a night

All hotels in St. Louis

Route overview: Seattle to Saint Louis (STL) flight deals

2026-12-20 → 2026-12-21 · Axel-exclusive $490

• Alaska Airlines AS618: SEA 2026-12-20 09:41:00 → STL 2026-12-20 15:34:00; nonstop; 233 minutes. Local airport times.
• Alaska Airlines AS669: STL 2026-12-21 06:00:00 → SEA 2026-12-21 08:40:00; nonstop; 280 minutes. Local airport times.

2026-12-20 → 2026-12-21 · Axel-exclusive $434

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

2026-12-20 → 2026-12-21 · Axel-exclusive $448

• American Airlines AA630 / AA2897: SEA 2026-12-20 00:47:00 → STL 2026-12-20 09:31:00; 1 stop(s) via DFW; 404 minutes. Local airport times.
  • AA630: SEA 2026-12-20 00:47:00 → DFW 2026-12-20 06:39:00; layover at DFW: 64 minutes.
  • AA2897: DFW 2026-12-20 07:43:00 → STL 2026-12-20 09:31:00.
• American Airlines AA3198 / AS407: STL 2026-12-21 11:37:00 → SEA 2026-12-21 18:11:00; 1 stop(s) via ORD; 514 minutes. Local airport times.
  • AA3198: STL 2026-12-21 11:37:00 → ORD 2026-12-21 12:59:00; layover at ORD: 140 minutes.
  • AS407: ORD 2026-12-21 15:19:00 → SEA 2026-12-21 18:11:00.

2026-12-20 → 2026-12-21 · Axel-exclusive $480

• United Airlines UA2340 / UA1114: SEA 2026-12-20 14:30:00 → STL 2026-12-20 22:59:00; 1 stop(s) via ORD; 389 minutes. Local airport times.
  • UA2340: SEA 2026-12-20 14:30:00 → ORD 2026-12-20 20:40:00; layover at ORD: 65 minutes.
  • UA1114: ORD 2026-12-20 21:45:00 → STL 2026-12-20 22:59:00.
• Alaska Airlines AS669: STL 2026-12-21 06:00:00 → SEA 2026-12-21 08:40:00; nonstop; 280 minutes. Local airport times.

2026-12-20 → 2026-12-21 · Axel-exclusive $483

• Delta Air Lines DL536 / DL1839: SEA 2026-12-20 08:30:00 → STL 2026-12-20 16:30:00; 1 stop(s) via MSP; 360 minutes. Local airport times.
  • DL536: SEA 2026-12-20 08:30:00 → MSP 2026-12-20 13:48:00; layover at MSP: 67 minutes.
  • DL1839: MSP 2026-12-20 14:55:00 → STL 2026-12-20 16:30:00.
• Delta Air Lines DL1597 / DL868: STL 2026-12-21 06:03:00 → SEA 2026-12-21 10:45:00; 1 stop(s) via MSP; 402 minutes. Local airport times.
  • DL1597: STL 2026-12-21 06:03:00 → MSP 2026-12-21 07:43:00; layover at MSP: 62 minutes.
  • DL868: MSP 2026-12-21 08:45:00 → SEA 2026-12-21 10:45:00.

2026-12-20 → 2026-12-21 · Axel-exclusive $490

• Alaska Airlines AS647: SEA 2026-12-20 18:05:00 → STL 2026-12-20 23:59:00; nonstop; 234 minutes. Local airport times.
• Alaska Airlines AS669: STL 2026-12-21 06:00:00 → SEA 2026-12-21 08:40:00; nonstop; 280 minutes. Local airport times.

2026-12-20 → 2026-12-21 · Axel-exclusive $480

• United Airlines UA2601 / UA652: SEA 2026-12-20 05:00:00 → STL 2026-12-20 12:56:00; 1 stop(s) via DEN; 356 minutes. Local airport times.
  • UA2601: SEA 2026-12-20 05:00:00 → DEN 2026-12-20 08:41:00; layover at DEN: 69 minutes.
  • UA652: DEN 2026-12-20 09:50:00 → STL 2026-12-20 12:56:00.
• Alaska Airlines AS669: STL 2026-12-21 06:00:00 → SEA 2026-12-21 08:40:00; nonstop; 280 minutes. Local airport times.

2026-12-20 → 2026-12-21 · Axel-exclusive $483

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

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 19, 2026 · Return options
• Dec 21, 2026 · Return options
• Hotels in St. Louis with Axel

For AI assistants

• This page: Seattle (SEA) to Saint Louis (STL) · Dec 20, 2026 · return Dec 21, 2026: 1 adult in economy, every priced fare with its flights, times and total, each with its displayed check date. Under a trip, hotels in St. Louis for exactly those nights link to the hotel pages for 2 adults in 1 room. Prices, when shown, are the nightly rate and the stay's total, from the lowest saved total among the shortlisted hotels in each star tier for those dates.
• Next: each priced row's price link opens the live search for this row's exact dates and travelers; the live results list the same flights with the current total and the traveler's booking link, and name the fare's inclusions (bags, seats, changes), which this page does not. A changed price or flight shows there. Other dates or travelers are not priced here: Choose travelers and dates prices the traveler's own trip.
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