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

Boston → Saint Louis

Dec 8, 2026 · return Dec 10, 2026

BOS → STL1 adulteconomyRound trip

10 flight options · 5 airlines

Nonstop flights

Tue, Dec 8 – Thu, Dec 10

Southwest Airlines
5:05 pmBOS
3h 10m
Nonstop
7:15 pmSTL
Southwest Airlines
10:15 amSTL
2h 30m
Nonstop
1:45 pmBOS

Round-trip total · 1 adult · Taxes included

Tue, Dec 8 – Thu, Dec 10

American Airlines
3:25 pmBOS
3h 22m
Nonstop
5:47 pmSTL
American Airlines
9:59 amSTL
2h 37m
Nonstop
1:36 pmBOS

Round-trip total · 1 adult · Taxes included

Tue, Dec 8 – Thu, Dec 10

Southwest Airlines
6:50 pmBOS
3h 10m
Nonstop
9:00 pmSTL
Southwest Airlines
6:10 pmSTL
2h 35m
Nonstop
9:45 pmBOS

Round-trip total · 1 adult · Taxes included

Tue, Dec 8 – Thu, Dec 10

American Airlines
7:00 amBOS
3h 29m
Nonstop
9:29 amSTL
American Airlines
9:59 amSTL
2h 37m
Nonstop
1:36 pmBOS

Round-trip total · 1 adult · Taxes included

One-stop flights

Tue, Dec 8 – Thu, Dec 10

Frontier Airlines
12:15 pmBOS
6h 27m
ATL · 1h 13m
5:42 pmSTL
Southwest Airlines
10:15 amSTL
2h 30m
Nonstop
1:45 pmBOS

Round-trip total · 1 adult · Taxes included

Tue, Dec 8 – Thu, Dec 10

United Airlines
5:45 amBOS
5h 27m
IAD · 1h 15m
10:12 amSTL
United Airlines
8:30 amSTL
5h 2m
IAD · 1h 15m
2:32 pmBOS

Round-trip total · 1 adult · Taxes included

Tue, Dec 8 – Thu, Dec 10

Delta Air Lines
1:04 pmBOS
5h 16m
DTW · 1h 14m
5:20 pmSTL
Delta Air Lines
10:14 amSTL
4h 50m
DTW · 1h 21m
4:04 pmBOS

Round-trip total · 1 adult · Taxes included

Tue, Dec 8 – Thu, Dec 10

Southwest Airlines
1:20 pmBOS
5h 45m
BWI · 1h 50m
6:05 pmSTL
Southwest Airlines
10:15 amSTL
2h 30m
Nonstop
1:45 pmBOS

Round-trip total · 1 adult · Taxes included

Tue, Dec 8 – Thu, Dec 10

American Airlines
5:00 amBOS
6h 19m
CLT · 1h 41m
10:19 amSTL
American Airlines
9:59 amSTL
2h 37m
Nonstop
1:36 pmBOS

Round-trip total · 1 adult · Taxes included

Tue, Dec 8 – Thu, Dec 10

American Airlines
4:00 pmBOS
5h 31m
PHL · 1h
8:31 pmSTL
American Airlines
9:59 amSTL
2h 37m
Nonstop
1:36 pmBOS

Round-trip total · 1 adult · Taxes included

Make this trip yours

BOS ⇄ STL

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 7, 2026 → Dec 9, 2026Dec 9, 2026 → Dec 11, 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: Boston to Saint Louis (STL) flight deals

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-08 → 2026-12-10Southwest AirlinesWN4929 / WN4918$280.002026-10-29T00:52:52Z
2026-12-08 → 2026-12-10American AirlinesAA4678 / AA3444$290.002026-10-29T00:52:52Z
2026-12-08 → 2026-12-10Frontier Airlines / Southwest AirlinesF93511 + F94473 / WN4918$230.002026-10-29T00:52:52Z
2026-12-08 → 2026-12-10United AirlinesUA1734 + UA4427 / UA4406 + UA1392$270.002026-10-29T00:52:52Z
2026-12-08 → 2026-12-10Delta Air LinesDL2222 + DL2822 / DL2868 + DL1171$280.002026-10-29T00:52:52Z
2026-12-08 → 2026-12-10Southwest AirlinesWN4929 / WN4431$280.002026-10-29T00:52:52Z
2026-12-08 → 2026-12-10American AirlinesAA3444 / AA3444$290.002026-10-29T00:52:52Z
2026-12-08 → 2026-12-10Southwest AirlinesWN1888 + WN2730 / WN4918$270.002026-10-29T00:52:52Z
2026-12-08 → 2026-12-10American AirlinesAA1249 + AA2486 / AA3444$275.002026-10-29T00:52:52Z
2026-12-08 → 2026-12-10American AirlinesAA1198 + AA5224 / AA3444$275.002026-10-29T00:52:52Z

2026-12-08 → 2026-12-10 · $280.00

  • Southwest Airlines WN4929: BOS 2026-12-08 17:05:00 → STL 2026-12-08 19:15:00; nonstop; 190 minutes. Local airport times.
  • Southwest Airlines WN4918: STL 2026-12-10 10:15:00 → BOS 2026-12-10 13:45:00; nonstop; 150 minutes. Local airport times.

2026-12-08 → 2026-12-10 · $290.00

  • American Airlines AA4678: BOS 2026-12-08 15:25:00 → STL 2026-12-08 17:47:00; nonstop; 202 minutes. Local airport times.
  • American Airlines AA3444: STL 2026-12-10 09:59:00 → BOS 2026-12-10 13:36:00; nonstop; 157 minutes. Local airport times.

2026-12-08 → 2026-12-10 · $230.00

  • Frontier Airlines F93511 / F94473: BOS 2026-12-08 12:15:00 → STL 2026-12-08 17:42:00; 1 stop(s) via ATL; 387 minutes. Local airport times.
    • F93511: BOS 2026-12-08 12:15:00 → ATL 2026-12-08 15:36:00; layover at ATL: 73 minutes.
    • F94473: ATL 2026-12-08 16:49:00 → STL 2026-12-08 17:42:00.
  • Southwest Airlines WN4918: STL 2026-12-10 10:15:00 → BOS 2026-12-10 13:45:00; nonstop; 150 minutes. Local airport times.

2026-12-08 → 2026-12-10 · $270.00

  • United Airlines UA1734 / UA4427: BOS 2026-12-08 05:45:00 → STL 2026-12-08 10:12:00; 1 stop(s) via IAD; 327 minutes. Local airport times.
    • UA1734: BOS 2026-12-08 05:45:00 → IAD 2026-12-08 07:25:00; layover at IAD: 75 minutes.
    • UA4427: IAD 2026-12-08 08:40:00 → STL 2026-12-08 10:12:00.
  • United Airlines UA4406 / UA1392: STL 2026-12-10 08:30:00 → BOS 2026-12-10 14:32:00; 1 stop(s) via IAD; 302 minutes. Local airport times.
    • UA4406: STL 2026-12-10 08:30:00 → IAD 2026-12-10 11:35:00; layover at IAD: 75 minutes.
    • UA1392: IAD 2026-12-10 12:50:00 → BOS 2026-12-10 14:32:00.

2026-12-08 → 2026-12-10 · $280.00

  • Delta Air Lines DL2222 / DL2822: BOS 2026-12-08 13:04:00 → STL 2026-12-08 17:20:00; 1 stop(s) via DTW; 316 minutes. Local airport times.
    • DL2222: BOS 2026-12-08 13:04:00 → DTW 2026-12-08 15:19:00; layover at DTW: 74 minutes.
    • DL2822: DTW 2026-12-08 16:33:00 → STL 2026-12-08 17:20:00.
  • Delta Air Lines DL2868 / DL1171: STL 2026-12-10 10:14:00 → BOS 2026-12-10 16:04:00; 1 stop(s) via DTW; 290 minutes. Local airport times.
    • DL2868: STL 2026-12-10 10:14:00 → DTW 2026-12-10 12:46:00; layover at DTW: 81 minutes.
    • DL1171: DTW 2026-12-10 14:07:00 → BOS 2026-12-10 16:04:00.

2026-12-08 → 2026-12-10 · $280.00

  • Southwest Airlines WN4929: BOS 2026-12-08 18:50:00 → STL 2026-12-08 21:00:00; nonstop; 190 minutes. Local airport times.
  • Southwest Airlines WN4431: STL 2026-12-10 18:10:00 → BOS 2026-12-10 21:45:00; nonstop; 155 minutes. Local airport times.

2026-12-08 → 2026-12-10 · $290.00

  • American Airlines AA3444: BOS 2026-12-08 07:00:00 → STL 2026-12-08 09:29:00; nonstop; 209 minutes. Local airport times.
  • American Airlines AA3444: STL 2026-12-10 09:59:00 → BOS 2026-12-10 13:36:00; nonstop; 157 minutes. Local airport times.

2026-12-08 → 2026-12-10 · $270.00

  • Southwest Airlines WN1888 / WN2730: BOS 2026-12-08 13:20:00 → STL 2026-12-08 18:05:00; 1 stop(s) via BWI; 345 minutes. Local airport times.
    • WN1888: BOS 2026-12-08 13:20:00 → BWI 2026-12-08 14:55:00; layover at BWI: 110 minutes.
    • WN2730: BWI 2026-12-08 16:45:00 → STL 2026-12-08 18:05:00.
  • Southwest Airlines WN4918: STL 2026-12-10 10:15:00 → BOS 2026-12-10 13:45:00; nonstop; 150 minutes. Local airport times.

2026-12-08 → 2026-12-10 · $275.00

  • American Airlines AA1249 / AA2486: BOS 2026-12-08 05:00:00 → STL 2026-12-08 10:19:00; 1 stop(s) via CLT; 379 minutes. Local airport times.
    • AA1249: BOS 2026-12-08 05:00:00 → CLT 2026-12-08 07:34:00; layover at CLT: 101 minutes.
    • AA2486: CLT 2026-12-08 09:15:00 → STL 2026-12-08 10:19:00.
  • American Airlines AA3444: STL 2026-12-10 09:59:00 → BOS 2026-12-10 13:36:00; nonstop; 157 minutes. Local airport times.

2026-12-08 → 2026-12-10 · $275.00

  • American Airlines AA1198 / AA5224: BOS 2026-12-08 16:00:00 → STL 2026-12-08 20:31:00; 1 stop(s) via PHL; 331 minutes. Local airport times.
    • AA1198: BOS 2026-12-08 16:00:00 → PHL 2026-12-08 17:40:00; layover at PHL: 60 minutes.
    • AA5224: PHL 2026-12-08 18:40:00 → STL 2026-12-08 20:31:00.
  • American Airlines AA3444: STL 2026-12-10 09:59:00 → BOS 2026-12-10 13:36:00; nonstop; 157 minutes. Local airport times.

Explore this route

For AI assistants

  • This page: Boston (BOS) to Saint Louis (STL) · Dec 8, 2026 · return Dec 10, 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 Boston 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. 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.