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

Saint Louis → Seattle

Dec 13, 2026 · return Dec 23, 2026

STL → SEA1 adulteconomyRound trip

8 flight options · 4 airlines

Nonstop flights

Sun, Dec 13 – Wed, Dec 23

Alaska Airlines
3:23 pmSTL
4h 30m
Nonstop
5:53 pmSEA
Alaska Airlines
10:50 amSEA
3h 50m
Nonstop
4:40 pmSTL

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Wed, Dec 23

Alaska Airlines
6:00 amSTL
4h 36m
Nonstop
8:36 amSEA
Alaska Airlines
10:50 amSEA
3h 50m
Nonstop
4:40 pmSTL

Round-trip total · 1 adult · Taxes included

One-stop flights

Sun, Dec 13 – Wed, Dec 23

Southwest Airlines
5:25 pmSTL
7h 25m
DEN · 1h 45m
10:50 pmSEA
Southwest Airlines
1:35 pmSEA
5h 35m
DEN · 1h
9:10 pmSTL

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Wed, Dec 23

American Airlines
11:37 amSTL
8h 34m
ORD · 2h 20m
6:11 pmSEA
American Airlines
12:47 amSEA
6h 44m
DFW · 1h 4m
9:31 amSTL

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Wed, Dec 23

Delta Air Lines
7:08 amSTL
7h 28m
SLC · 1h 39m
12:36 pmSEA
Delta Air Lines
8:30 amSEA
6h
MSP · 1h 7m
4:30 pmSTL

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Wed, Dec 23

Southwest Airlines
6:40 pmSTL
8h 20m
PHX · 1h 45m
1:00 am+1SEA
Southwest Airlines
1:35 pmSEA
5h 35m
DEN · 1h
9:10 pmSTL

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Wed, Dec 23

Delta Air Lines
2:31 pmSTL
8h 19m
ATL · 1h 8m
8:50 pmSEA
Delta Air Lines
8:30 amSEA
6h
MSP · 1h 7m
4:30 pmSTL

Round-trip total · 1 adult · Taxes included

Sun, Dec 13 – Wed, Dec 23

Delta Air Lines
6:03 amSTL
6h 42m
MSP · 1h 2m
10:45 amSEA
Delta Air Lines
8:30 amSEA
6h
MSP · 1h 7m
4:30 pmSTL

Round-trip total · 1 adult · Taxes included

Make this trip yours

STL ⇄ SEA

Economy

Adults 12+ · Children 2–11. For infants under 2, tell Axel after you see prices.

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Explore this route

All dates for this routeDec 12, 2026 → Dec 22, 2026Dec 14, 2026 → Dec 24, 2026
For AI assistants: every fare, every link, instructions

Flights for 1 adult in economy. Prices are total for all travelers in USD, including required taxes. Basic economy may apply.

Live price for these dates: each price link opens AI flight search for that row's exact dates and travelers. Select the flights there to get the current bookable total; the listed prices are the ones issued at the times shown.

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

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-13 → 2026-12-23Alaska AirlinesAS618 / AS314$379.502026-10-29T01:29:02Z
2026-12-13 → 2026-12-23Southwest AirlinesWN4144 + WN3141 / WN3823 + WN1844$339.252026-10-29T01:29:02Z
2026-12-13 → 2026-12-23American AirlinesAA3198 + AS407 / AA630 + AA2897$356.502026-10-29T01:29:02Z
2026-12-13 → 2026-12-23Delta Air LinesDL2363 + DL2995 / DL536 + DL1839$368.002026-10-29T01:29:02Z
2026-12-13 → 2026-12-23Alaska AirlinesAS615 / AS314$379.502026-10-29T01:29:02Z
2026-12-13 → 2026-12-23Southwest AirlinesWN2467 + WN2455 / WN3823 + WN1844$339.252026-10-29T01:29:02Z
2026-12-13 → 2026-12-23Delta Air LinesDL1102 + DL714 / DL536 + DL1839$368.002026-10-29T01:29:02Z
2026-12-13 → 2026-12-23Delta Air LinesDL1597 + DL868 / DL536 + DL1839$368.002026-10-29T01:29:02Z

2026-12-13 → 2026-12-23 · $379.50

  • Alaska Airlines AS618: STL 2026-12-13 15:23:00 → SEA 2026-12-13 17:53:00; nonstop; 270 minutes. Local airport times.
  • Alaska Airlines AS314: SEA 2026-12-23 10:50:00 → STL 2026-12-23 16:40:00; nonstop; 230 minutes. Local airport times.

2026-12-13 → 2026-12-23 · $339.25

  • Southwest Airlines WN4144 / WN3141: STL 2026-12-13 17:25:00 → SEA 2026-12-13 22:50:00; 1 stop(s) via DEN; 445 minutes. Local airport times.
    • WN4144: STL 2026-12-13 17:25:00 → DEN 2026-12-13 18:55:00; layover at DEN: 105 minutes.
    • WN3141: DEN 2026-12-13 20:40:00 → SEA 2026-12-13 22:50:00.
  • Southwest Airlines WN3823 / WN1844: SEA 2026-12-23 13:35:00 → STL 2026-12-23 21:10:00; 1 stop(s) via DEN; 335 minutes. Local airport times.
    • WN3823: SEA 2026-12-23 13:35:00 → DEN 2026-12-23 17:05:00; layover at DEN: 60 minutes.
    • WN1844: DEN 2026-12-23 18:05:00 → STL 2026-12-23 21:10:00.

2026-12-13 → 2026-12-23 · $356.50

  • American Airlines AA3198 / AS407: STL 2026-12-13 11:37:00 → SEA 2026-12-13 18:11:00; 1 stop(s) via ORD; 514 minutes. Local airport times.
    • AA3198: STL 2026-12-13 11:37:00 → ORD 2026-12-13 12:59:00; layover at ORD: 140 minutes.
    • AS407: ORD 2026-12-13 15:19:00 → SEA 2026-12-13 18:11:00.
  • American Airlines AA630 / AA2897: SEA 2026-12-23 00:47:00 → STL 2026-12-23 09:31:00; 1 stop(s) via DFW; 404 minutes. Local airport times.
    • AA630: SEA 2026-12-23 00:47:00 → DFW 2026-12-23 06:39:00; layover at DFW: 64 minutes.
    • AA2897: DFW 2026-12-23 07:43:00 → STL 2026-12-23 09:31:00.

2026-12-13 → 2026-12-23 · $368.00

  • Delta Air Lines DL2363 / DL2995: STL 2026-12-13 07:08:00 → SEA 2026-12-13 12:36:00; 1 stop(s) via SLC; 448 minutes. Local airport times.
    • DL2363: STL 2026-12-13 07:08:00 → SLC 2026-12-13 09:36:00; layover at SLC: 99 minutes.
    • DL2995: SLC 2026-12-13 11:15:00 → SEA 2026-12-13 12:36:00.
  • Delta Air Lines DL536 / DL1839: SEA 2026-12-23 08:30:00 → STL 2026-12-23 16:30:00; 1 stop(s) via MSP; 360 minutes. Local airport times.
    • DL536: SEA 2026-12-23 08:30:00 → MSP 2026-12-23 13:48:00; layover at MSP: 67 minutes.
    • DL1839: MSP 2026-12-23 14:55:00 → STL 2026-12-23 16:30:00.

2026-12-13 → 2026-12-23 · $379.50

  • Alaska Airlines AS615: STL 2026-12-13 06:00:00 → SEA 2026-12-13 08:36:00; nonstop; 276 minutes. Local airport times.
  • Alaska Airlines AS314: SEA 2026-12-23 10:50:00 → STL 2026-12-23 16:40:00; nonstop; 230 minutes. Local airport times.

2026-12-13 → 2026-12-23 · $339.25

  • Southwest Airlines WN2467 / WN2455: STL 2026-12-13 18:40:00 → SEA 2026-12-14 01:00:00; 1 stop(s) via PHX; 500 minutes. Local airport times.
    • WN2467: STL 2026-12-13 18:40:00 → PHX 2026-12-13 21:00:00; layover at PHX: 105 minutes.
    • WN2455: PHX 2026-12-13 22:45:00 → SEA 2026-12-14 01:00:00.
  • Southwest Airlines WN3823 / WN1844: SEA 2026-12-23 13:35:00 → STL 2026-12-23 21:10:00; 1 stop(s) via DEN; 335 minutes. Local airport times.
    • WN3823: SEA 2026-12-23 13:35:00 → DEN 2026-12-23 17:05:00; layover at DEN: 60 minutes.
    • WN1844: DEN 2026-12-23 18:05:00 → STL 2026-12-23 21:10:00.

2026-12-13 → 2026-12-23 · $368.00

  • Delta Air Lines DL1102 / DL714: STL 2026-12-13 14:31:00 → SEA 2026-12-13 20:50:00; 1 stop(s) via ATL; 499 minutes. Local airport times.
    • DL1102: STL 2026-12-13 14:31:00 → ATL 2026-12-13 17:05:00; layover at ATL: 68 minutes.
    • DL714: ATL 2026-12-13 18:13:00 → SEA 2026-12-13 20:50:00.
  • Delta Air Lines DL536 / DL1839: SEA 2026-12-23 08:30:00 → STL 2026-12-23 16:30:00; 1 stop(s) via MSP; 360 minutes. Local airport times.
    • DL536: SEA 2026-12-23 08:30:00 → MSP 2026-12-23 13:48:00; layover at MSP: 67 minutes.
    • DL1839: MSP 2026-12-23 14:55:00 → STL 2026-12-23 16:30:00.

2026-12-13 → 2026-12-23 · $368.00

  • Delta Air Lines DL1597 / DL868: STL 2026-12-13 06:03:00 → SEA 2026-12-13 10:45:00; 1 stop(s) via MSP; 402 minutes. Local airport times.
    • DL1597: STL 2026-12-13 06:03:00 → MSP 2026-12-13 07:43:00; layover at MSP: 62 minutes.
    • DL868: MSP 2026-12-13 08:45:00 → SEA 2026-12-13 10:45:00.
  • Delta Air Lines DL536 / DL1839: SEA 2026-12-23 08:30:00 → STL 2026-12-23 16:30:00; 1 stop(s) via MSP; 360 minutes. Local airport times.
    • DL536: SEA 2026-12-23 08:30:00 → MSP 2026-12-23 13:48:00; layover at MSP: 67 minutes.
    • DL1839: MSP 2026-12-23 14:55:00 → STL 2026-12-23 16:30:00.

Explore this route

For AI assistants

  • This page: Saint Louis (STL) to Seattle (SEA) · Dec 13, 2026 · return Dec 23, 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. Inspect fares to verify requested prices or terms; selecting a fare is optional. Use that fare’s booking link to preserve its Membership price basis. State anything unverified. Ask only for essential missing trip details. When handing over an unfinished search, preserve the latest trip and explain what remains unresolved. Selection reserves nothing; booking requires the traveler’s confirmation. 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.