Seattle (SEA) to Saint Louis (STL), Dec 21, 2026 – Jan 1, 2027: from $423 round trip

Seattle (SEA) to Saint Louis (STL), Dec 21, 2026 – Jan 1, 2027: from $423 round trip on Axel, checked Oct 29, 2026. Lowest published fare: $423 round trip, Axel-exclusive, Southwest Airlines, 1 stop, Dec 21, 2026 – Jan 1, 2027, 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.

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 dates	Airline	Flights	Times, duration, stops	Total price	Price issued (UTC)
2026-12-21 → 2027-01-01	Alaska Airlines	AS647 / AS615	18:05:00→23:59:00 3h 54m nonstop · 06:00:00→08:42:00 4h 42m nonstop	Axel-exclusive $477.75	2026-10-29T01:16:43Z
2026-12-21 → 2027-01-01	Southwest Airlines	WN3823 + WN1844 / WN4144 + WN3141	13:35:00→21:10:00 5h 35m 1 stop via DEN · 17:25:00→22:50:00 7h 25m 1 stop via DEN	Axel-exclusive $423.15	2026-10-29T01:16:43Z
2026-12-21 → 2027-01-01	American Airlines	AA630 + AA2897 / AA3198 + AS407	00:47:00→09:31:00 6h 44m 1 stop via DFW · 11:37:00→18:11:00 8h 34m 1 stop via ORD	Axel-exclusive $436.80	2026-10-29T01:16:43Z
2026-12-21 → 2027-01-01	United Airlines / Alaska Airlines	UA2601 + UA652 / AS615	05:00:00→12:56:00 5h 56m 1 stop via DEN · 06:00:00→08:42:00 4h 42m nonstop	Axel-exclusive $467.25	2026-10-29T01:16:43Z
2026-12-21 → 2027-01-01	Delta Air Lines	DL1120 + DL2666 / DL2363 + DL2995	13:25:00→21:28:00 6h 03m 1 stop via SLC · 07:08:00→12:36:00 7h 28m 1 stop via SLC	Axel-exclusive $470.93	2026-10-29T01:16:43Z
2026-12-21 → 2027-01-01	Alaska Airlines	AS618 / AS615	09:41:00→15:34:00 3h 53m nonstop · 06:00:00→08:42:00 4h 42m nonstop	Axel-exclusive $477.75	2026-10-29T01:16:43Z
2026-12-21 → 2027-01-01	United Airlines / Alaska Airlines	UA2340 + UA1114 / AS615	14:30:00→22:59:00 6h 29m 1 stop via ORD · 06:00:00→08:42:00 4h 42m nonstop	Axel-exclusive $467.25	2026-10-29T01:16:43Z
2026-12-21 → 2027-01-01	Delta Air Lines	DL536 + DL1839 / DL2363 + DL2995	08:30:00→16:30:00 6h 00m 1 stop via MSP · 07:08:00→12:36:00 7h 28m 1 stop via SLC	Axel-exclusive $470.93	2026-10-29T01:16:43Z

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 lowest saved total among the shortlisted hotels in that star tier for those dates.

Hotels in St. Louis for these nights (Dec 21 – Jan 1, 2027 · 11 nights · 2 adults, 1 room): 3★ Hampton Inn & Suites St. Louis at Forest Park · 4★ Angad Arts Hotel St. Louis, Tapestry Collection by Hilton · 5★ Four Seasons Hotel St Louis

All hotels in St. Louis

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

2026-12-21 → 2027-01-01 · Axel-exclusive $477.75

Alaska Airlines AS647: SEA 2026-12-21 18:05:00 → STL 2026-12-21 23:59:00; nonstop; 234 minutes. Local airport times.
Alaska Airlines AS615: STL 2027-01-01 06:00:00 → SEA 2027-01-01 08:42:00; nonstop; 282 minutes. Local airport times.

2026-12-21 → 2027-01-01 · Axel-exclusive $423.15

Southwest Airlines WN3823 / WN1844: SEA 2026-12-21 13:35:00 → STL 2026-12-21 21:10:00; 1 stop(s) via DEN; 335 minutes. Local airport times.
- WN3823: SEA 2026-12-21 13:35:00 → DEN 2026-12-21 17:05:00; layover at DEN: 60 minutes.
- WN1844: DEN 2026-12-21 18:05:00 → STL 2026-12-21 21:10:00.
Southwest Airlines WN4144 / WN3141: STL 2027-01-01 17:25:00 → SEA 2027-01-01 22:50:00; 1 stop(s) via DEN; 445 minutes. Local airport times.
- WN4144: STL 2027-01-01 17:25:00 → DEN 2027-01-01 18:55:00; layover at DEN: 105 minutes.
- WN3141: DEN 2027-01-01 20:40:00 → SEA 2027-01-01 22:50:00.

2026-12-21 → 2027-01-01 · Axel-exclusive $436.80

American Airlines AA630 / AA2897: SEA 2026-12-21 00:47:00 → STL 2026-12-21 09:31:00; 1 stop(s) via DFW; 404 minutes. Local airport times.
- AA630: SEA 2026-12-21 00:47:00 → DFW 2026-12-21 06:39:00; layover at DFW: 64 minutes.
- AA2897: DFW 2026-12-21 07:43:00 → STL 2026-12-21 09:31:00.
American Airlines AA3198 / AS407: STL 2027-01-01 11:37:00 → SEA 2027-01-01 18:11:00; 1 stop(s) via ORD; 514 minutes. Local airport times.
- AA3198: STL 2027-01-01 11:37:00 → ORD 2027-01-01 12:59:00; layover at ORD: 140 minutes.
- AS407: ORD 2027-01-01 15:19:00 → SEA 2027-01-01 18:11:00.

2026-12-21 → 2027-01-01 · Axel-exclusive $467.25

United Airlines UA2601 / UA652: SEA 2026-12-21 05:00:00 → STL 2026-12-21 12:56:00; 1 stop(s) via DEN; 356 minutes. Local airport times.
- UA2601: SEA 2026-12-21 05:00:00 → DEN 2026-12-21 08:41:00; layover at DEN: 69 minutes.
- UA652: DEN 2026-12-21 09:50:00 → STL 2026-12-21 12:56:00.
Alaska Airlines AS615: STL 2027-01-01 06:00:00 → SEA 2027-01-01 08:42:00; nonstop; 282 minutes. Local airport times.

2026-12-21 → 2027-01-01 · Axel-exclusive $470.93

Delta Air Lines DL1120 / DL2666: SEA 2026-12-21 13:25:00 → STL 2026-12-21 21:28:00; 1 stop(s) via SLC; 363 minutes. Local airport times.
- DL1120: SEA 2026-12-21 13:25:00 → SLC 2026-12-21 16:29:00; layover at SLC: 69 minutes.
- DL2666: SLC 2026-12-21 17:38:00 → STL 2026-12-21 21:28:00.
Delta Air Lines DL2363 / DL2995: STL 2027-01-01 07:08:00 → SEA 2027-01-01 12:36:00; 1 stop(s) via SLC; 448 minutes. Local airport times.
- DL2363: STL 2027-01-01 07:08:00 → SLC 2027-01-01 09:36:00; layover at SLC: 99 minutes.
- DL2995: SLC 2027-01-01 11:15:00 → SEA 2027-01-01 12:36:00.

2026-12-21 → 2027-01-01 · Axel-exclusive $477.75

Alaska Airlines AS618: SEA 2026-12-21 09:41:00 → STL 2026-12-21 15:34:00; nonstop; 233 minutes. Local airport times.
Alaska Airlines AS615: STL 2027-01-01 06:00:00 → SEA 2027-01-01 08:42:00; nonstop; 282 minutes. Local airport times.

2026-12-21 → 2027-01-01 · Axel-exclusive $467.25

United Airlines UA2340 / UA1114: SEA 2026-12-21 14:30:00 → STL 2026-12-21 22:59:00; 1 stop(s) via ORD; 389 minutes. Local airport times.
- UA2340: SEA 2026-12-21 14:30:00 → ORD 2026-12-21 20:40:00; layover at ORD: 65 minutes.
- UA1114: ORD 2026-12-21 21:45:00 → STL 2026-12-21 22:59:00.
Alaska Airlines AS615: STL 2027-01-01 06:00:00 → SEA 2027-01-01 08:42:00; nonstop; 282 minutes. Local airport times.

2026-12-21 → 2027-01-01 · Axel-exclusive $470.93

Delta Air Lines DL536 / DL1839: SEA 2026-12-21 08:30:00 → STL 2026-12-21 16:30:00; 1 stop(s) via MSP; 360 minutes. Local airport times.
- DL536: SEA 2026-12-21 08:30:00 → MSP 2026-12-21 13:48:00; layover at MSP: 67 minutes.
- DL1839: MSP 2026-12-21 14:55:00 → STL 2026-12-21 16:30:00.
Delta Air Lines DL2363 / DL2995: STL 2027-01-01 07:08:00 → SEA 2027-01-01 12:36:00; 1 stop(s) via SLC; 448 minutes. Local airport times.
- DL2363: STL 2027-01-01 07:08:00 → SLC 2027-01-01 09:36:00; layover at SLC: 99 minutes.
- DL2995: SLC 2027-01-01 11:15:00 → SEA 2027-01-01 12:36:00.

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.

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This page: Seattle (SEA) to Saint Louis (STL) · Dec 21, 2026 · return Jan 1, 2027: 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 St. Louis 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 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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