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

Saint Louis (STL) to Seattle (SEA), Dec 16, 2026: round trips from $295, one way from $150

Saint Louis (STL) to Seattle (SEA), Dec 16, 2026: round trips from $295, one way from $150 on Axel, checked Oct 29, 2026. Lowest published fares: $295 round trip, Axel-exclusive, Southwest Airlines, 1 stop, Dec 16–17, 2026; $150 one way, Axel-exclusive, Southwest Airlines, 1 stop, Dec 16, 2026; 1 adult, economy, checked Oct 29, 2026.

STL → SEA1 adulteconomyOne way and round trips

30 flight options · 2 airlines

Choose your return date

One-way flights and round trips by duration. Flights for 1 adult in economy. Prices are total for all travelers in USD, including required taxes. Basic economy may apply.

December 2026

Flights for your trip

  1. Wed, Dec 16 · One way

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

    One-way total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  2. Wed, Dec 16 · One way

    Alaska Airlines
    6:00 amSTL
    4h 36m
    Nonstop
    8:36 amSEA

    One-way total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  3. Wed, Dec 16 – Thu, Dec 17

    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

    Availability is checked when you select these flights.

  4. Wed, Dec 16 – Thu, Dec 17

    Alaska Airlines
    6:00 amSTL
    4h 36m
    Nonstop
    8:36 amSEA
    Alaska Airlines
    6:05 pmSEA
    3h 54m
    Nonstop
    11:59 pmSTL

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  5. Wed, Dec 16 – Fri, Dec 18

    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

    Availability is checked when you select these flights.

  6. Wed, Dec 16 – Fri, Dec 18

    Alaska Airlines
    6:00 amSTL
    4h 36m
    Nonstop
    8:36 amSEA
    Alaska Airlines
    9:05 amSEA
    3h 51m
    Nonstop
    2:56 pmSTL

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  7. Wed, Dec 16 – Sat, Dec 19

    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

    Availability is checked when you select these flights.

  8. Wed, Dec 16 – Sat, Dec 19

    Alaska Airlines
    6:00 amSTL
    4h 36m
    Nonstop
    8:36 amSEA
    Alaska Airlines
    6:05 pmSEA
    3h 54m
    Nonstop
    11:59 pmSTL

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  9. Wed, Dec 16 – Sun, Dec 20

    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

    Availability is checked when you select these flights.

  10. Wed, Dec 16 – Sun, Dec 20

    Alaska Airlines
    6:00 amSTL
    4h 36m
    Nonstop
    8:36 amSEA
    Alaska Airlines
    6:05 pmSEA
    3h 54m
    Nonstop
    11:59 pmSTL

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  11. Wed, Dec 16 – Tue, Dec 22

    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

    Availability is checked when you select these flights.

  12. Wed, Dec 16 – Tue, Dec 22

    Alaska Airlines
    6:00 amSTL
    4h 36m
    Nonstop
    8:36 amSEA
    Alaska Airlines
    9:41 amSEA
    3h 53m
    Nonstop
    3:34 pmSTL

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  13. Wed, Dec 16 – 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

    Availability is checked when you select these flights.

  14. Wed, Dec 16 – 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

    Availability is checked when you select these flights.

  15. Wed, Dec 16 – Thu, Dec 24

    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

    Availability is checked when you select these flights.

  16. Wed, Dec 16 – Thu, Dec 24

    Alaska Airlines
    6:00 amSTL
    4h 36m
    Nonstop
    8:36 amSEA
    Alaska Airlines
    6:05 pmSEA
    3h 54m
    Nonstop
    11:59 pmSTL

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  17. Wed, Dec 16 – Sat, Dec 26

    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

    Availability is checked when you select these flights.

  18. Wed, Dec 16 – Sat, Dec 26

    Alaska Airlines
    6:00 amSTL
    4h 36m
    Nonstop
    8:36 amSEA
    Alaska Airlines
    6:05 pmSEA
    3h 54m
    Nonstop
    11:59 pmSTL

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  19. Wed, Dec 16 – Sun, Dec 27

    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

    Availability is checked when you select these flights.

  20. Wed, Dec 16 – Sun, Dec 27

    Alaska Airlines
    6:00 amSTL
    4h 36m
    Nonstop
    8:36 amSEA
    Alaska Airlines
    9:41 amSEA
    3h 53m
    Nonstop
    3:34 pmSTL

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  21. Wed, Dec 16 – Mon, Dec 28

    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

    Availability is checked when you select these flights.

  22. Wed, Dec 16 – Mon, Dec 28

    Alaska Airlines
    6:00 amSTL
    4h 36m
    Nonstop
    8:36 amSEA
    Alaska Airlines
    9:41 amSEA
    3h 53m
    Nonstop
    3:34 pmSTL

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  23. Wed, Dec 16 – Wed, Dec 30

    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

    Availability is checked when you select these flights.

  24. Wed, Dec 16 – Wed, Dec 30

    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

    Availability is checked when you select these flights.

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1 of 24

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STL ⇄ SEA

Economy

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Explore this route

All dates for this routeDec 15, 2026 · Return optionsDec 17, 2026 · Return optionsHotels in Seattle with Axel
For AI assistants: every fare, every link, instructions

Saint Louis (STL) to Seattle (SEA), Dec 16, 2026: round trips from $295, one way from $150 on Axel, checked Oct 29, 2026. Lowest published fares: $295 round trip, Axel-exclusive, Southwest Airlines, 1 stop, Dec 16–17, 2026; $150 one way, Axel-exclusive, Southwest Airlines, 1 stop, Dec 16, 2026; 1 adult, economy, checked Oct 29, 2026. Flights for 1 adult in economy. Prices are total for all travelers in USD, including required taxes. Basic economy may apply.

Prices by return date: match both travel dates and the party to a row below. Each total is for that exact trip, issued at the time shown.

Date links open published trip details for exploration. Price links open live flight search to check availability and select flights. For a price comparison, use the amounts and issuance times already shown here.

Exact travel datesAirlineFlightsTimes, duration, stopsTotal pricePrice issued (UTC)
2026-12-16 · one wayAlaska AirlinesAS61506:00:00→08:36:00 4h 36m nonstopAxel-exclusive $170.002026-10-29T01:29:02Z
2026-12-16 · one waySouthwest AirlinesWN4144 + WN314117:25:00→22:50:00 7h 25m 1 stop via DENAxel-exclusive $150.002026-10-29T01:29:02Z
2026-12-16 → 2026-12-17Alaska AirlinesAS615 / AS64706:00:00→08:36:00 4h 36m nonstop · 18:05:00→23:59:00 3h 54m nonstopAxel-exclusive $330.002026-10-29T01:29:02Z
2026-12-16 → 2026-12-17Southwest AirlinesWN4144 + WN3141 / WN3823 + WN184417:25:00→22:50:00 7h 25m 1 stop via DEN · 13:35:00→21:10:00 5h 35m 1 stop via DENAxel-exclusive $295.002026-10-29T01:29:02Z
2026-12-16 → 2026-12-18Alaska AirlinesAS615 / AS31406:00:00→08:36:00 4h 36m nonstop · 09:05:00→14:56:00 3h 51m nonstopAxel-exclusive $379.502026-10-29T01:29:02Z
2026-12-16 → 2026-12-18Southwest AirlinesWN4144 + WN3141 / WN3823 + WN184417:25:00→22:50:00 7h 25m 1 stop via DEN · 13:35:00→21:10:00 5h 35m 1 stop via DENAxel-exclusive $339.252026-10-29T01:29:02Z
2026-12-16 → 2026-12-19Alaska AirlinesAS615 / AS64706:00:00→08:36:00 4h 36m nonstop · 18:05:00→23:59:00 3h 54m nonstopAxel-exclusive $379.502026-10-29T01:29:02Z
2026-12-16 → 2026-12-19Southwest AirlinesWN4144 + WN3141 / WN3823 + WN184417:25:00→22:50:00 7h 25m 1 stop via DEN · 13:35:00→21:10:00 5h 35m 1 stop via DENAxel-exclusive $339.252026-10-29T01:29:02Z
2026-12-16 → 2026-12-20Alaska AirlinesAS615 / AS64706:00:00→08:36:00 4h 36m nonstop · 18:05:00→23:59:00 3h 54m nonstopAxel-exclusive $379.502026-10-29T01:29:02Z
2026-12-16 → 2026-12-20Southwest AirlinesWN4144 + WN3141 / WN3823 + WN184417:25:00→22:50:00 7h 25m 1 stop via DEN · 13:35:00→21:10:00 5h 35m 1 stop via DENAxel-exclusive $339.252026-10-29T01:29:02Z
2026-12-16 → 2026-12-21Alaska AirlinesAS615 / AS64706:00:00→08:36:00 4h 36m nonstop · 18:05:00→23:59:00 3h 54m nonstopAxel-exclusive $379.502026-10-29T01:29:02Z
2026-12-16 → 2026-12-21Southwest AirlinesWN4144 + WN3141 / WN3823 + WN184417:25:00→22:50:00 7h 25m 1 stop via DEN · 13:35:00→21:10:00 5h 35m 1 stop via DENAxel-exclusive $339.252026-10-29T01:29:02Z
2026-12-16 → 2026-12-22Alaska AirlinesAS615 / AS61806:00:00→08:36:00 4h 36m nonstop · 09:41:00→15:34:00 3h 53m nonstopAxel-exclusive $379.502026-10-29T01:29:02Z
2026-12-16 → 2026-12-22Southwest AirlinesWN4144 + WN3141 / WN3823 + WN184417:25:00→22:50:00 7h 25m 1 stop via DEN · 13:35:00→21:10:00 5h 35m 1 stop via DENAxel-exclusive $339.252026-10-29T01:29:02Z
2026-12-16 → 2026-12-23Alaska AirlinesAS615 / AS31406:00:00→08:36:00 4h 36m nonstop · 10:50:00→16:40:00 3h 50m nonstopAxel-exclusive $379.502026-10-29T01:29:02Z
2026-12-16 → 2026-12-23Southwest AirlinesWN4144 + WN3141 / WN3823 + WN184417:25:00→22:50:00 7h 25m 1 stop via DEN · 13:35:00→21:10:00 5h 35m 1 stop via DENAxel-exclusive $339.252026-10-29T01:29:02Z
2026-12-16 → 2026-12-24Alaska AirlinesAS615 / AS64706:00:00→08:36:00 4h 36m nonstop · 18:05:00→23:59:00 3h 54m nonstopAxel-exclusive $379.502026-10-29T01:29:02Z
2026-12-16 → 2026-12-24Southwest AirlinesWN4144 + WN3141 / WN3823 + WN184417:25:00→22:50:00 7h 25m 1 stop via DEN · 13:35:00→21:10:00 5h 35m 1 stop via DENAxel-exclusive $339.252026-10-29T01:29:02Z
2026-12-16 → 2026-12-25Alaska AirlinesAS615 / AS31406:00:00→08:36:00 4h 36m nonstop · 09:05:00→14:56:00 3h 51m nonstopAxel-exclusive $379.502026-10-29T01:29:02Z
2026-12-16 → 2026-12-25Southwest AirlinesWN4144 + WN3141 / WN3823 + WN184417:25:00→22:50:00 7h 25m 1 stop via DEN · 13:35:00→21:10:00 5h 35m 1 stop via DENAxel-exclusive $339.252026-10-29T01:29:02Z
2026-12-16 → 2026-12-26Alaska AirlinesAS615 / AS64706:00:00→08:36:00 4h 36m nonstop · 18:05:00→23:59:00 3h 54m nonstopAxel-exclusive $379.502026-10-29T01:29:02Z
2026-12-16 → 2026-12-26Southwest AirlinesWN4144 + WN3141 / WN3823 + WN184417:25:00→22:50:00 7h 25m 1 stop via DEN · 13:35:00→21:10:00 5h 35m 1 stop via DENAxel-exclusive $339.252026-10-29T01:29:02Z
2026-12-16 → 2026-12-27Alaska AirlinesAS615 / AS61806:00:00→08:36:00 4h 36m nonstop · 09:41:00→15:34:00 3h 53m nonstopAxel-exclusive $379.502026-10-29T01:29:02Z
2026-12-16 → 2026-12-27Southwest AirlinesWN4144 + WN3141 / WN3823 + WN184417:25:00→22:50:00 7h 25m 1 stop via DEN · 13:35:00→21:10:00 5h 35m 1 stop via DENAxel-exclusive $339.252026-10-29T01:29:02Z
2026-12-16 → 2026-12-28Alaska AirlinesAS615 / AS61806:00:00→08:36:00 4h 36m nonstop · 09:41:00→15:34:00 3h 53m nonstopAxel-exclusive $379.502026-10-29T01:29:02Z
2026-12-16 → 2026-12-28Southwest AirlinesWN4144 + WN3141 / WN3823 + WN184417:25:00→22:50:00 7h 25m 1 stop via DEN · 13:35:00→21:10:00 5h 35m 1 stop via DENAxel-exclusive $339.252026-10-29T01:29:02Z
2026-12-16 → 2026-12-29Alaska AirlinesAS615 / AS61806:00:00→08:36:00 4h 36m nonstop · 09:41:00→15:34:00 3h 53m nonstopAxel-exclusive $379.502026-10-29T01:29:02Z
2026-12-16 → 2026-12-29Southwest AirlinesWN4144 + WN3141 / WN3823 + WN184417:25:00→22:50:00 7h 25m 1 stop via DEN · 13:35:00→21:10:00 5h 35m 1 stop via DENAxel-exclusive $339.252026-10-29T01:29:02Z
2026-12-16 → 2026-12-30Alaska AirlinesAS615 / AS31406:00:00→08:36:00 4h 36m nonstop · 10:50:00→16:40:00 3h 50m nonstopAxel-exclusive $379.502026-10-29T01:29:02Z
2026-12-16 → 2026-12-30Southwest AirlinesWN4144 + WN3141 / WN3823 + WN184417:25:00→22:50:00 7h 25m 1 stop via DEN · 13:35:00→21:10:00 5h 35m 1 stop via DENAxel-exclusive $339.252026-10-29T01:29:02Z

Hotels in Seattle for these trips

Hotels: under a trip, hotels in Seattle for exactly those nights link to the hotel pages for 2 adults in 1 room. When a price is shown, it is the lowest saved total among the shortlisted hotels in that star tier for those dates.

All hotels in Seattle

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

2026-12-16 · one way · Axel-exclusive $150.00

  • Southwest Airlines WN4144 / WN3141: STL 2026-12-16 17:25:00 → SEA 2026-12-16 22:50:00; 1 stop(s) via DEN; 445 minutes. Local airport times.
    • WN4144: STL 2026-12-16 17:25:00 → DEN 2026-12-16 18:55:00; layover at DEN: 105 minutes.
    • WN3141: DEN 2026-12-16 20:40:00 → SEA 2026-12-16 22:50:00.

2026-12-16 · one way · Axel-exclusive $170.00

  • Alaska Airlines AS615: STL 2026-12-16 06:00:00 → SEA 2026-12-16 08:36:00; nonstop; 276 minutes. Local airport times.

2026-12-16 → 2026-12-17 · Axel-exclusive $295.00

  • Southwest Airlines WN4144 / WN3141: STL 2026-12-16 17:25:00 → SEA 2026-12-16 22:50:00; 1 stop(s) via DEN; 445 minutes. Local airport times.
    • WN4144: STL 2026-12-16 17:25:00 → DEN 2026-12-16 18:55:00; layover at DEN: 105 minutes.
    • WN3141: DEN 2026-12-16 20:40:00 → SEA 2026-12-16 22:50:00.
  • Southwest Airlines WN3823 / WN1844: SEA 2026-12-17 13:35:00 → STL 2026-12-17 21:10:00; 1 stop(s) via DEN; 335 minutes. Local airport times.
    • WN3823: SEA 2026-12-17 13:35:00 → DEN 2026-12-17 17:05:00; layover at DEN: 60 minutes.
    • WN1844: DEN 2026-12-17 18:05:00 → STL 2026-12-17 21:10:00.

2026-12-16 → 2026-12-17 · Axel-exclusive $330.00

  • Alaska Airlines AS615: STL 2026-12-16 06:00:00 → SEA 2026-12-16 08:36:00; nonstop; 276 minutes. Local airport times.
  • Alaska Airlines AS647: SEA 2026-12-17 18:05:00 → STL 2026-12-17 23:59:00; nonstop; 234 minutes. Local airport times.

2026-12-16 → 2026-12-18 · Axel-exclusive $339.25

  • Southwest Airlines WN4144 / WN3141: STL 2026-12-16 17:25:00 → SEA 2026-12-16 22:50:00; 1 stop(s) via DEN; 445 minutes. Local airport times.
    • WN4144: STL 2026-12-16 17:25:00 → DEN 2026-12-16 18:55:00; layover at DEN: 105 minutes.
    • WN3141: DEN 2026-12-16 20:40:00 → SEA 2026-12-16 22:50:00.
  • Southwest Airlines WN3823 / WN1844: SEA 2026-12-18 13:35:00 → STL 2026-12-18 21:10:00; 1 stop(s) via DEN; 335 minutes. Local airport times.
    • WN3823: SEA 2026-12-18 13:35:00 → DEN 2026-12-18 17:05:00; layover at DEN: 60 minutes.
    • WN1844: DEN 2026-12-18 18:05:00 → STL 2026-12-18 21:10:00.

2026-12-16 → 2026-12-18 · Axel-exclusive $379.50

  • Alaska Airlines AS615: STL 2026-12-16 06:00:00 → SEA 2026-12-16 08:36:00; nonstop; 276 minutes. Local airport times.
  • Alaska Airlines AS314: SEA 2026-12-18 09:05:00 → STL 2026-12-18 14:56:00; nonstop; 231 minutes. Local airport times.

2026-12-16 → 2026-12-19 · Axel-exclusive $339.25

  • Southwest Airlines WN4144 / WN3141: STL 2026-12-16 17:25:00 → SEA 2026-12-16 22:50:00; 1 stop(s) via DEN; 445 minutes. Local airport times.
    • WN4144: STL 2026-12-16 17:25:00 → DEN 2026-12-16 18:55:00; layover at DEN: 105 minutes.
    • WN3141: DEN 2026-12-16 20:40:00 → SEA 2026-12-16 22:50:00.
  • 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.

2026-12-16 → 2026-12-19 · Axel-exclusive $379.50

  • Alaska Airlines AS615: STL 2026-12-16 06:00:00 → SEA 2026-12-16 08:36:00; nonstop; 276 minutes. Local airport times.
  • Alaska Airlines AS647: SEA 2026-12-19 18:05:00 → STL 2026-12-19 23:59:00; nonstop; 234 minutes. Local airport times.

2026-12-16 → 2026-12-20 · Axel-exclusive $339.25

  • Southwest Airlines WN4144 / WN3141: STL 2026-12-16 17:25:00 → SEA 2026-12-16 22:50:00; 1 stop(s) via DEN; 445 minutes. Local airport times.
    • WN4144: STL 2026-12-16 17:25:00 → DEN 2026-12-16 18:55:00; layover at DEN: 105 minutes.
    • WN3141: DEN 2026-12-16 20:40:00 → SEA 2026-12-16 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.

2026-12-16 → 2026-12-20 · Axel-exclusive $379.50

  • Alaska Airlines AS615: STL 2026-12-16 06:00:00 → SEA 2026-12-16 08:36:00; nonstop; 276 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.

2026-12-16 → 2026-12-22 · Axel-exclusive $339.25

  • Southwest Airlines WN4144 / WN3141: STL 2026-12-16 17:25:00 → SEA 2026-12-16 22:50:00; 1 stop(s) via DEN; 445 minutes. Local airport times.
    • WN4144: STL 2026-12-16 17:25:00 → DEN 2026-12-16 18:55:00; layover at DEN: 105 minutes.
    • WN3141: DEN 2026-12-16 20:40:00 → SEA 2026-12-16 22:50:00.
  • Southwest Airlines WN3823 / WN1844: SEA 2026-12-22 13:35:00 → STL 2026-12-22 21:10:00; 1 stop(s) via DEN; 335 minutes. Local airport times.
    • WN3823: SEA 2026-12-22 13:35:00 → DEN 2026-12-22 17:05:00; layover at DEN: 60 minutes.
    • WN1844: DEN 2026-12-22 18:05:00 → STL 2026-12-22 21:10:00.

2026-12-16 → 2026-12-22 · Axel-exclusive $379.50

  • Alaska Airlines AS615: STL 2026-12-16 06:00:00 → SEA 2026-12-16 08:36:00; nonstop; 276 minutes. Local airport times.
  • Alaska Airlines AS618: SEA 2026-12-22 09:41:00 → STL 2026-12-22 15:34:00; nonstop; 233 minutes. Local airport times.

2026-12-16 → 2026-12-23 · Axel-exclusive $339.25

  • Southwest Airlines WN4144 / WN3141: STL 2026-12-16 17:25:00 → SEA 2026-12-16 22:50:00; 1 stop(s) via DEN; 445 minutes. Local airport times.
    • WN4144: STL 2026-12-16 17:25:00 → DEN 2026-12-16 18:55:00; layover at DEN: 105 minutes.
    • WN3141: DEN 2026-12-16 20:40:00 → SEA 2026-12-16 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.

2026-12-16 → 2026-12-23 · Axel-exclusive $379.50

  • Alaska Airlines AS615: STL 2026-12-16 06:00:00 → SEA 2026-12-16 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.

2026-12-16 → 2026-12-24 · Axel-exclusive $339.25

  • Southwest Airlines WN4144 / WN3141: STL 2026-12-16 17:25:00 → SEA 2026-12-16 22:50:00; 1 stop(s) via DEN; 445 minutes. Local airport times.
    • WN4144: STL 2026-12-16 17:25:00 → DEN 2026-12-16 18:55:00; layover at DEN: 105 minutes.
    • WN3141: DEN 2026-12-16 20:40:00 → SEA 2026-12-16 22:50:00.
  • Southwest Airlines WN3823 / WN1844: SEA 2026-12-24 13:35:00 → STL 2026-12-24 21:10:00; 1 stop(s) via DEN; 335 minutes. Local airport times.
    • WN3823: SEA 2026-12-24 13:35:00 → DEN 2026-12-24 17:05:00; layover at DEN: 60 minutes.
    • WN1844: DEN 2026-12-24 18:05:00 → STL 2026-12-24 21:10:00.

2026-12-16 → 2026-12-24 · Axel-exclusive $379.50

  • Alaska Airlines AS615: STL 2026-12-16 06:00:00 → SEA 2026-12-16 08:36:00; nonstop; 276 minutes. Local airport times.
  • Alaska Airlines AS647: SEA 2026-12-24 18:05:00 → STL 2026-12-24 23:59:00; nonstop; 234 minutes. Local airport times.

2026-12-16 → 2026-12-26 · Axel-exclusive $339.25

  • Southwest Airlines WN4144 / WN3141: STL 2026-12-16 17:25:00 → SEA 2026-12-16 22:50:00; 1 stop(s) via DEN; 445 minutes. Local airport times.
    • WN4144: STL 2026-12-16 17:25:00 → DEN 2026-12-16 18:55:00; layover at DEN: 105 minutes.
    • WN3141: DEN 2026-12-16 20:40:00 → SEA 2026-12-16 22:50:00.
  • Southwest Airlines WN3823 / WN1844: SEA 2026-12-26 13:35:00 → STL 2026-12-26 21:10:00; 1 stop(s) via DEN; 335 minutes. Local airport times.
    • WN3823: SEA 2026-12-26 13:35:00 → DEN 2026-12-26 17:05:00; layover at DEN: 60 minutes.
    • WN1844: DEN 2026-12-26 18:05:00 → STL 2026-12-26 21:10:00.

2026-12-16 → 2026-12-26 · Axel-exclusive $379.50

  • Alaska Airlines AS615: STL 2026-12-16 06:00:00 → SEA 2026-12-16 08:36:00; nonstop; 276 minutes. Local airport times.
  • Alaska Airlines AS647: SEA 2026-12-26 18:05:00 → STL 2026-12-26 23:59:00; nonstop; 234 minutes. Local airport times.

2026-12-16 → 2026-12-27 · Axel-exclusive $339.25

  • Southwest Airlines WN4144 / WN3141: STL 2026-12-16 17:25:00 → SEA 2026-12-16 22:50:00; 1 stop(s) via DEN; 445 minutes. Local airport times.
    • WN4144: STL 2026-12-16 17:25:00 → DEN 2026-12-16 18:55:00; layover at DEN: 105 minutes.
    • WN3141: DEN 2026-12-16 20:40:00 → SEA 2026-12-16 22:50:00.
  • Southwest Airlines WN3823 / WN1844: SEA 2026-12-27 13:35:00 → STL 2026-12-27 21:10:00; 1 stop(s) via DEN; 335 minutes. Local airport times.
    • WN3823: SEA 2026-12-27 13:35:00 → DEN 2026-12-27 17:05:00; layover at DEN: 60 minutes.
    • WN1844: DEN 2026-12-27 18:05:00 → STL 2026-12-27 21:10:00.

2026-12-16 → 2026-12-27 · Axel-exclusive $379.50

  • Alaska Airlines AS615: STL 2026-12-16 06:00:00 → SEA 2026-12-16 08:36:00; nonstop; 276 minutes. Local airport times.
  • Alaska Airlines AS618: SEA 2026-12-27 09:41:00 → STL 2026-12-27 15:34:00; nonstop; 233 minutes. Local airport times.

2026-12-16 → 2026-12-28 · Axel-exclusive $339.25

  • Southwest Airlines WN4144 / WN3141: STL 2026-12-16 17:25:00 → SEA 2026-12-16 22:50:00; 1 stop(s) via DEN; 445 minutes. Local airport times.
    • WN4144: STL 2026-12-16 17:25:00 → DEN 2026-12-16 18:55:00; layover at DEN: 105 minutes.
    • WN3141: DEN 2026-12-16 20:40:00 → SEA 2026-12-16 22:50:00.
  • Southwest Airlines WN3823 / WN1844: SEA 2026-12-28 13:35:00 → STL 2026-12-28 21:10:00; 1 stop(s) via DEN; 335 minutes. Local airport times.
    • WN3823: SEA 2026-12-28 13:35:00 → DEN 2026-12-28 17:05:00; layover at DEN: 60 minutes.
    • WN1844: DEN 2026-12-28 18:05:00 → STL 2026-12-28 21:10:00.

2026-12-16 → 2026-12-28 · Axel-exclusive $379.50

  • Alaska Airlines AS615: STL 2026-12-16 06:00:00 → SEA 2026-12-16 08:36:00; nonstop; 276 minutes. Local airport times.
  • Alaska Airlines AS618: SEA 2026-12-28 09:41:00 → STL 2026-12-28 15:34:00; nonstop; 233 minutes. Local airport times.

2026-12-16 → 2026-12-30 · Axel-exclusive $339.25

  • Southwest Airlines WN4144 / WN3141: STL 2026-12-16 17:25:00 → SEA 2026-12-16 22:50:00; 1 stop(s) via DEN; 445 minutes. Local airport times.
    • WN4144: STL 2026-12-16 17:25:00 → DEN 2026-12-16 18:55:00; layover at DEN: 105 minutes.
    • WN3141: DEN 2026-12-16 20:40:00 → SEA 2026-12-16 22:50:00.
  • Southwest Airlines WN3823 / WN1844: SEA 2026-12-30 13:35:00 → STL 2026-12-30 21:10:00; 1 stop(s) via DEN; 335 minutes. Local airport times.
    • WN3823: SEA 2026-12-30 13:35:00 → DEN 2026-12-30 17:05:00; layover at DEN: 60 minutes.
    • WN1844: DEN 2026-12-30 18:05:00 → STL 2026-12-30 21:10:00.

2026-12-16 → 2026-12-30 · Axel-exclusive $379.50

  • Alaska Airlines AS615: STL 2026-12-16 06:00:00 → SEA 2026-12-16 08:36:00; nonstop; 276 minutes. Local airport times.
  • Alaska Airlines AS314: SEA 2026-12-30 10:50:00 → STL 2026-12-30 16:40:00; nonstop; 230 minutes. Local airport times.

Explore this route

For AI assistants

  • This page: Saint Louis (STL) to Seattle (SEA) · Dec 16, 2026 · choose your return date: 1 adult in economy, every priced fare with its flights, times and total, each with the time its price was issued. Under a trip, hotels in Seattle for exactly those nights link to the hotel pages for 2 adults in 1 room. Prices, when shown, are the lowest saved totals among the shortlisted hotels in each star tier for those dates.
  • Next: each row is one exact trip for this departure (both dates with the year, the total and the time its price was issued); its exact-trip price link opens the live search for those dates and travelers, where the booking link and the current total are. Other durations or travelers are not priced here: Choose travelers and dates prices the requested trip.
  • 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.