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Boston → Saint Louis

Dec 8, 2026 · return Dec 22, 2026

BOS → STL1 adulteconomyRound trip

10 flight options · 5 airlines

Nonstop flights

Tue, Dec 8 – Tue, Dec 22

Southwest Airlines
6:50 pmBOS
3h 10m
Nonstop
9:00 pmSTL
Southwest Airlines
10:15 amSTL
2h 30m
Nonstop
1:45 pmBOS

Round-trip total · 1 adult · Taxes included

Tue, Dec 8 – Tue, Dec 22

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

Tue, Dec 8 – Tue, Dec 22

Southwest Airlines
5:05 pmBOS
3h 10m
Nonstop
7:15 pmSTL
Southwest Airlines
1:20 pmSTL
2h 30m
Nonstop
4:50 pmBOS

Round-trip total · 1 adult · Taxes included

Tue, Dec 8 – Tue, Dec 22

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

One-stop flights

Tue, Dec 8 – Tue, Dec 22

Frontier Airlines
12:15 pmBOS
6h 27m
ATL · 1h 13m
5:42 pmSTL
Southwest Airlines
1:20 pmSTL
2h 30m
Nonstop
4:50 pmBOS

Round-trip total · 1 adult · Taxes included

Tue, Dec 8 – Tue, Dec 22

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 – Tue, Dec 22

Delta Air Lines
1:04 pmBOS
5h 16m
DTW · 1h 14m
5:20 pmSTL
Delta Air Lines
10:00 amSTL
5h 25m
LGA · 1h 34m
4:25 pmBOS

Round-trip total · 1 adult · Taxes included

Tue, Dec 8 – Tue, Dec 22

Southwest Airlines
1:20 pmBOS
5h 45m
BWI · 1h 50m
6:05 pmSTL
Southwest Airlines
1:20 pmSTL
2h 30m
Nonstop
4:50 pmBOS

Round-trip total · 1 adult · Taxes included

Tue, Dec 8 – Tue, Dec 22

American Airlines
7:00 amBOS
3h 16m
Nonstop
9:16 amSTL
American Airlines
12:54 pmSTL
5h 25m
CLT · 1h 24m
7:19 pmBOS

Round-trip total · 1 adult · Taxes included

Tue, Dec 8 – Tue, Dec 22

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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More dates

All dates for this routeNov 5, 2026 → Nov 8, 2026Nov 14, 2026 → Nov 21, 2026Nov 24, 2026 → Nov 29, 2026Dec 5, 2026 → Dec 12, 2026Dec 17, 2026 → Dec 20, 2026Dec 26, 2026 → Jan 2, 2027Jan 5, 2027 · One wayJan 16, 2027 → Jan 23, 2027Feb 5, 2027 → Feb 8, 2027Apr 3, 2027 → Apr 10, 2027Jun 26, 2027 → Jul 3, 2027Sep 17, 2027 → Sep 20, 2027
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.

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-08 → 2026-12-22Southwest AirlinesWN4929 / WN4918$329.002026-10-29T00:52:52Z
2026-12-08 → 2026-12-22American AirlinesAA3444 / AA3444$340.752026-10-29T00:52:52Z
2026-12-08 → 2026-12-22Frontier Airlines / Southwest AirlinesF93511 + F94473 / WN3667$279.002026-10-29T00:52:52Z
2026-12-08 → 2026-12-22United AirlinesUA1734 + UA4427 / UA4406 + UA1392$317.252026-10-29T00:52:52Z
2026-12-08 → 2026-12-22Delta Air LinesDL2222 + DL2822 / DL5041 + DL5727$329.002026-10-29T00:52:52Z
2026-12-08 → 2026-12-22Southwest AirlinesWN4929 / WN3667$329.002026-10-29T00:52:52Z
2026-12-08 → 2026-12-22American AirlinesAA4678 / AA3444$340.752026-10-29T00:52:52Z
2026-12-08 → 2026-12-22Southwest AirlinesWN1888 + WN2730 / WN3667$319.002026-10-29T00:52:52Z
2026-12-08 → 2026-12-22American AirlinesAA3444 / AA2486 + AA1828$320.502026-10-29T00:52:52Z
2026-12-08 → 2026-12-22American AirlinesAA1198 + AA5224 / AA3444$325.752026-10-29T00:52:52Z

2026-12-08 → 2026-12-22 · $329.00

  • 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 WN4918: STL 2026-12-22 10:15:00 → BOS 2026-12-22 13:45:00; nonstop; 150 minutes. Local airport times.

2026-12-08 → 2026-12-22 · $340.75

  • 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 2026-12-22 09:59:00 → BOS 2026-12-22 13:36:00; nonstop; 157 minutes. Local airport times.

2026-12-08 → 2026-12-22 · $279.00

  • 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 WN3667: STL 2026-12-22 13:20:00 → BOS 2026-12-22 16:50:00; nonstop; 150 minutes. Local airport times.

2026-12-08 → 2026-12-22 · $317.25

  • 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 2026-12-22 08:30:00 → BOS 2026-12-22 14:32:00; 1 stop(s) via IAD; 302 minutes. Local airport times.
    • UA4406: STL 2026-12-22 08:30:00 → IAD 2026-12-22 11:35:00; layover at IAD: 75 minutes.
    • UA1392: IAD 2026-12-22 12:50:00 → BOS 2026-12-22 14:32:00.

2026-12-08 → 2026-12-22 · $329.00

  • 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 DL5041 / DL5727: STL 2026-12-22 10:00:00 → BOS 2026-12-22 16:25:00; 1 stop(s) via LGA; 325 minutes. Local airport times.
    • DL5041: STL 2026-12-22 10:00:00 → LGA 2026-12-22 13:26:00; layover at LGA: 94 minutes.
    • DL5727: LGA 2026-12-22 15:00:00 → BOS 2026-12-22 16:25:00.

2026-12-08 → 2026-12-22 · $329.00

  • 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 WN3667: STL 2026-12-22 13:20:00 → BOS 2026-12-22 16:50:00; nonstop; 150 minutes. Local airport times.

2026-12-08 → 2026-12-22 · $340.75

  • 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 2026-12-22 09:59:00 → BOS 2026-12-22 13:36:00; nonstop; 157 minutes. Local airport times.

2026-12-08 → 2026-12-22 · $319.00

  • 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 WN3667: STL 2026-12-22 13:20:00 → BOS 2026-12-22 16:50:00; nonstop; 150 minutes. Local airport times.

2026-12-08 → 2026-12-22 · $320.50

  • American Airlines AA3444: BOS 2026-12-08 07:00:00 → STL 2026-12-08 09:16:00; nonstop; 196 minutes. Local airport times.
  • American Airlines AA2486 / AA1828: STL 2026-12-22 12:54:00 → BOS 2026-12-22 19:19:00; 1 stop(s) via CLT; 325 minutes. Local airport times.
    • AA2486: STL 2026-12-22 12:54:00 → CLT 2026-12-22 15:42:00; layover at CLT: 84 minutes.
    • AA1828: CLT 2026-12-22 17:06:00 → BOS 2026-12-22 19:19:00.

2026-12-08 → 2026-12-22 · $325.75

  • 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 2026-12-22 09:59:00 → BOS 2026-12-22 13:36:00; nonstop; 157 minutes. Local airport times.

More dates for this route