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

Seattle → Saint Louis

Jan 21, 2027 · return Jan 23, 2027

SEA → STL1 adulteconomyRound trip

8 flight options · 5 airlines

Nonstop flights

Thu, Jan 21 – Sat, Jan 23

Alaska Airlines
6:05 pmSEA
3h 54m
Nonstop
11:59 pmSTL
Alaska Airlines
6:00 amSTL
4h 42m
Nonstop
8:42 amSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sat, Jan 23

Alaska Airlines
9:41 amSEA
3h 53m
Nonstop
3:34 pmSTL
Alaska Airlines
6:00 amSTL
4h 42m
Nonstop
8:42 amSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

One-stop flights

Thu, Jan 21 – Sat, Jan 23

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

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sat, Jan 23

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

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sat, Jan 23

United Airlines
2:30 pmSEA
6h 29m
ORD · 1h 5m
10:59 pmSTL
Alaska Airlines
6:00 amSTL
4h 42m
Nonstop
8:42 amSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sat, Jan 23

Delta Air Lines
1:25 pmSEA
6h 3m
SLC · 1h 9m
9:28 pmSTL
Delta Air Lines
2:31 pmSTL
8h 19m
ATL · 1h 8m
8:50 pmSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sat, Jan 23

United Airlines
5:00 amSEA
5h 56m
DEN · 1h 9m
12:56 pmSTL
Alaska Airlines
6:00 amSTL
4h 42m
Nonstop
8:42 amSEA

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Thu, Jan 21 – Sat, Jan 23

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

Round-trip total · 1 adult · Taxes included

Availability is checked when you select these flights.

Make this trip yours

SEA ⇄ STL

Economy

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

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Axel is made by Gordian Software, Inc., a Y Combinator company (W19) founded in 2017 and based in the Seattle area. The company is led by CEO Stephen Grabowski, formerly of Skyscanner. How Axel works · About

Explore this route

All dates for this routeJan 20, 2027 · Return optionsJan 22, 2027 · Return optionsHotels in St. Louis with Axel
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.

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.

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2027-01-21 → 2027-01-23Alaska AirlinesAS647 / AS615Axel-exclusive $332.502026-10-29T01:16:43Z
2027-01-21 → 2027-01-23Southwest AirlinesWN3823 + WN1844 / WN2467 + WN2455Axel-exclusive $294.502026-10-29T01:16:43Z
2027-01-21 → 2027-01-23American AirlinesAA630 + AA2897 / AA3198 + AS407Axel-exclusive $304.002026-10-29T01:16:43Z
2027-01-21 → 2027-01-23United Airlines / Alaska AirlinesUA2340 + UA1114 / AS615Axel-exclusive $325.382026-10-29T01:16:43Z
2027-01-21 → 2027-01-23Delta Air LinesDL1120 + DL2666 / DL1102 + DL714Axel-exclusive $327.762026-10-29T01:16:43Z
2027-01-21 → 2027-01-23Alaska AirlinesAS618 / AS615Axel-exclusive $332.502026-10-29T01:16:43Z
2027-01-21 → 2027-01-23United Airlines / Alaska AirlinesUA2601 + UA652 / AS615Axel-exclusive $325.382026-10-29T01:16:43Z
2027-01-21 → 2027-01-23Delta Air LinesDL536 + DL1839 / DL1102 + DL714Axel-exclusive $327.762026-10-29T01:16:43Z

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

2027-01-21 → 2027-01-23 · Axel-exclusive $332.50

  • Alaska Airlines AS647: SEA 2027-01-21 18:05:00 → STL 2027-01-21 23:59:00; nonstop; 234 minutes. Local airport times.
  • Alaska Airlines AS615: STL 2027-01-23 06:00:00 → SEA 2027-01-23 08:42:00; nonstop; 282 minutes. Local airport times.

2027-01-21 → 2027-01-23 · Axel-exclusive $294.50

  • Southwest Airlines WN3823 / WN1844: SEA 2027-01-21 13:35:00 → STL 2027-01-21 21:10:00; 1 stop(s) via DEN; 335 minutes. Local airport times.
    • WN3823: SEA 2027-01-21 13:35:00 → DEN 2027-01-21 17:05:00; layover at DEN: 60 minutes.
    • WN1844: DEN 2027-01-21 18:05:00 → STL 2027-01-21 21:10:00.
  • Southwest Airlines WN2467 / WN2455: STL 2027-01-23 18:40:00 → SEA 2027-01-24 01:00:00; 1 stop(s) via PHX; 500 minutes. Local airport times.
    • WN2467: STL 2027-01-23 18:40:00 → PHX 2027-01-23 21:00:00; layover at PHX: 105 minutes.
    • WN2455: PHX 2027-01-23 22:45:00 → SEA 2027-01-24 01:00:00.

2027-01-21 → 2027-01-23 · Axel-exclusive $304.00

  • American Airlines AA630 / AA2897: SEA 2027-01-21 00:47:00 → STL 2027-01-21 09:31:00; 1 stop(s) via DFW; 404 minutes. Local airport times.
    • AA630: SEA 2027-01-21 00:47:00 → DFW 2027-01-21 06:39:00; layover at DFW: 64 minutes.
    • AA2897: DFW 2027-01-21 07:43:00 → STL 2027-01-21 09:31:00.
  • American Airlines AA3198 / AS407: STL 2027-01-23 11:37:00 → SEA 2027-01-23 18:11:00; 1 stop(s) via ORD; 514 minutes. Local airport times.
    • AA3198: STL 2027-01-23 11:37:00 → ORD 2027-01-23 12:59:00; layover at ORD: 140 minutes.
    • AS407: ORD 2027-01-23 15:19:00 → SEA 2027-01-23 18:11:00.

2027-01-21 → 2027-01-23 · Axel-exclusive $325.38

  • United Airlines UA2340 / UA1114: SEA 2027-01-21 14:30:00 → STL 2027-01-21 22:59:00; 1 stop(s) via ORD; 389 minutes. Local airport times.
    • UA2340: SEA 2027-01-21 14:30:00 → ORD 2027-01-21 20:40:00; layover at ORD: 65 minutes.
    • UA1114: ORD 2027-01-21 21:45:00 → STL 2027-01-21 22:59:00.
  • Alaska Airlines AS615: STL 2027-01-23 06:00:00 → SEA 2027-01-23 08:42:00; nonstop; 282 minutes. Local airport times.

2027-01-21 → 2027-01-23 · Axel-exclusive $327.76

  • Delta Air Lines DL1120 / DL2666: SEA 2027-01-21 13:25:00 → STL 2027-01-21 21:28:00; 1 stop(s) via SLC; 363 minutes. Local airport times.
    • DL1120: SEA 2027-01-21 13:25:00 → SLC 2027-01-21 16:29:00; layover at SLC: 69 minutes.
    • DL2666: SLC 2027-01-21 17:38:00 → STL 2027-01-21 21:28:00.
  • Delta Air Lines DL1102 / DL714: STL 2027-01-23 14:31:00 → SEA 2027-01-23 20:50:00; 1 stop(s) via ATL; 499 minutes. Local airport times.
    • DL1102: STL 2027-01-23 14:31:00 → ATL 2027-01-23 17:05:00; layover at ATL: 68 minutes.
    • DL714: ATL 2027-01-23 18:13:00 → SEA 2027-01-23 20:50:00.

2027-01-21 → 2027-01-23 · Axel-exclusive $332.50

  • Alaska Airlines AS618: SEA 2027-01-21 09:41:00 → STL 2027-01-21 15:34:00; nonstop; 233 minutes. Local airport times.
  • Alaska Airlines AS615: STL 2027-01-23 06:00:00 → SEA 2027-01-23 08:42:00; nonstop; 282 minutes. Local airport times.

2027-01-21 → 2027-01-23 · Axel-exclusive $325.38

  • United Airlines UA2601 / UA652: SEA 2027-01-21 05:00:00 → STL 2027-01-21 12:56:00; 1 stop(s) via DEN; 356 minutes. Local airport times.
    • UA2601: SEA 2027-01-21 05:00:00 → DEN 2027-01-21 08:41:00; layover at DEN: 69 minutes.
    • UA652: DEN 2027-01-21 09:50:00 → STL 2027-01-21 12:56:00.
  • Alaska Airlines AS615: STL 2027-01-23 06:00:00 → SEA 2027-01-23 08:42:00; nonstop; 282 minutes. Local airport times.

2027-01-21 → 2027-01-23 · Axel-exclusive $327.76

  • Delta Air Lines DL536 / DL1839: SEA 2027-01-21 08:30:00 → STL 2027-01-21 16:30:00; 1 stop(s) via MSP; 360 minutes. Local airport times.
    • DL536: SEA 2027-01-21 08:30:00 → MSP 2027-01-21 13:48:00; layover at MSP: 67 minutes.
    • DL1839: MSP 2027-01-21 14:55:00 → STL 2027-01-21 16:30:00.
  • Delta Air Lines DL1102 / DL714: STL 2027-01-23 14:31:00 → SEA 2027-01-23 20:50:00; 1 stop(s) via ATL; 499 minutes. Local airport times.
    • DL1102: STL 2027-01-23 14:31:00 → ATL 2027-01-23 17:05:00; layover at ATL: 68 minutes.
    • DL714: ATL 2027-01-23 18:13:00 → SEA 2027-01-23 20:50:00.

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For AI assistants

  • This page: Seattle (SEA) to Saint Louis (STL) · Jan 21, 2027 · return Jan 23, 2027: 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 Seattle to Saint Louis (STL) 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.