Saint Louis (STL) to Seattle (SEA) · Dec 10, 2026 · return Dec 20, 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

2026-12-10 → 2026-12-20 · Axel-exclusive $379.50

• Alaska Airlines AS618: STL 2026-12-10 16:04:00 → SEA 2026-12-10 18:44:00; nonstop; 280 minutes. Local airport times.
• Alaska Airlines AS647: SEA 2026-12-20 18:05:00 → STL 2026-12-20 23:59:00; nonstop; 234 minutes. Local airport times.

2026-12-10 → 2026-12-20 · Axel-exclusive $339.25

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

2026-12-10 → 2026-12-20 · Axel-exclusive $356.50

• American Airlines AA3198 / AS407: STL 2026-12-10 11:37:00 → SEA 2026-12-10 18:11:00; 1 stop(s) via ORD; 514 minutes. Local airport times.
  • AA3198: STL 2026-12-10 11:37:00 → ORD 2026-12-10 12:59:00; layover at ORD: 140 minutes.
  • AS407: ORD 2026-12-10 15:19:00 → SEA 2026-12-10 18:11:00.
• 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.

2026-12-10 → 2026-12-20 · Axel-exclusive $368.00

• Delta Air Lines DL1102 / DL714: STL 2026-12-10 14:31:00 → SEA 2026-12-10 20:50:00; 1 stop(s) via ATL; 499 minutes. Local airport times.
  • DL1102: STL 2026-12-10 14:31:00 → ATL 2026-12-10 17:05:00; layover at ATL: 68 minutes.
  • DL714: ATL 2026-12-10 18:13:00 → SEA 2026-12-10 20:50:00.
• 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.

2026-12-10 → 2026-12-20 · Axel-exclusive $379.50

• Alaska Airlines AS615: STL 2026-12-10 06:04:00 → SEA 2026-12-10 08:50:00; nonstop; 286 minutes. Local airport times.
• Alaska Airlines AS647: SEA 2026-12-20 18:05:00 → STL 2026-12-20 23:59:00; nonstop; 234 minutes. Local airport times.

2026-12-10 → 2026-12-20 · Axel-exclusive $339.25

• Southwest Airlines WN2467 / WN2455: STL 2026-12-10 18:40:00 → SEA 2026-12-11 01:00:00; 1 stop(s) via PHX; 500 minutes. Local airport times.
  • WN2467: STL 2026-12-10 18:40:00 → PHX 2026-12-10 21:00:00; layover at PHX: 105 minutes.
  • WN2455: PHX 2026-12-10 22:45:00 → SEA 2026-12-11 01:00:00.
• 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.

2026-12-10 → 2026-12-20 · Axel-exclusive $368.00

• Delta Air Lines DL1597 / DL868: STL 2026-12-10 06:03:00 → SEA 2026-12-10 10:45:00; 1 stop(s) via MSP; 402 minutes. Local airport times.
  • DL1597: STL 2026-12-10 06:03:00 → MSP 2026-12-10 07:43:00; layover at MSP: 62 minutes.
  • DL868: MSP 2026-12-10 08:45:00 → SEA 2026-12-10 10:45:00.
• 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.

2026-12-10 → 2026-12-20 · Axel-exclusive $368.00

• Delta Air Lines DL2363 / DL2995: STL 2026-12-10 07:08:00 → SEA 2026-12-10 12:36:00; 1 stop(s) via SLC; 448 minutes. Local airport times.
  • DL2363: STL 2026-12-10 07:08:00 → SLC 2026-12-10 09:36:00; layover at SLC: 99 minutes.
  • DL2995: SLC 2026-12-10 11:15:00 → SEA 2026-12-10 12:36:00.
• 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.

Explore this route

• All dates for this route
• Dec 9, 2026 · Return options
• Dec 11, 2026 · Return options
• Hotels in Seattle with Axel

For AI assistants

• This page: Saint Louis (STL) to Seattle (SEA) · Dec 10, 2026 · return Dec 20, 2026: 1 adult in economy, every priced fare with its flights, times and total, each with the time its price was issued.
• Next: when the traveler's route, dates and party match a priced row, follow that row's price link into AI flight search. Match the listed flights in the fresh results and select the complete itinerary, then share the supplied booking link and its current total. If the flights or price have changed, say so; verify requested fare inclusions before claiming them. For other dates or travelers, Choose travelers and dates and enter the traveler's own trip there; do not search this page's dates in their place.
• Follow supplied links. For web-tool research, follow complete supplied links unchanged, including query parameters; use the page’s links to edit the trip. Constructed URLs may be rejected before reaching Axel. A completed fresh trip opens flight results first. Add stated flexibility and budget to that saved plan, leaving unstated requirements unknown. Edits create a new snapshot; use its results and review links.
• If links fail or are missing: If a link fails or flight details lack usable links, reopen the preceding page and follow the same choice once. Keep refreshed links unchanged and preserve the trip and selections. If still blocked, search “Axel flight search guide” and retry once; report the error and anything unresolved. Recovery: Axel Saint Louis to Seattle (SEA) flight deals · Flight search guide.
• Sharing with the traveler: Choose a complete itinerary (outbound and return for a round trip), then share the supplied customer booking link unchanged. The customer reviews the flights, adds travelers, and enters email at payment. Do not collect email in chat. Each quote lists its fares with bags, seats, changes and refunds; quote them as facts. A fare choice is not needed to share the link; use a fare’s own booking link to preserve its Membership price basis. Ask only for essential missing trip details. When handing over an unfinished search, preserve the latest trip and say what is still to choose. If no supplied link matches the latest trip, construct https://helloaxel.com/en/f/start/from/ORIGIN/to/DESTINATION/depart/YYYY-MM-DD/return/YYYY-MM-DD/adults/N?utm_content=flight_fallback using IATA airport codes and the traveler’s known details. Omit unknowns; for one way replace /return/YYYY-MM-DD with /trip/oneway. Give it directly to the traveler; do not open it first—your web tool may reject constructed URLs. Complete links open Flight Guide and start searching. Preferences and advanced options.

Feedback (optional): Missing info · Axel issue