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Boston → Saint Louis

Jan 21, 2027 · return Feb 4, 2027

BOS → STL1 adulteconomyRound trip

10 flight options · 5 airlines

Nonstop flights

Thu, Jan 21 – Thu, Feb 4

Southwest Airlines
12:25 pmBOS
3h 5m
Nonstop
2:30 pmSTL
Southwest Airlines
10:15 amSTL
2h 30m
Nonstop
1:45 pmBOS

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

American Airlines
4:14 pmBOS
3h 26m
Nonstop
6:40 pmSTL
American Airlines
9:59 amSTL
2h 37m
Nonstop
1:36 pmBOS

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

Southwest Airlines
5:20 amBOS
3h 10m
Nonstop
7:30 amSTL
Southwest Airlines
10:15 amSTL
2h 30m
Nonstop
1:45 pmBOS

Round-trip total · 1 adult · Taxes included

Thu, Jan 21 – Thu, Feb 4

American Airlines
7:00 amBOS
3h 26m
Nonstop
9:26 amSTL
American Airlines
9:59 amSTL
2h 37m
Nonstop
1:36 pmBOS

Round-trip total · 1 adult · Taxes included

One-stop flights

Thu, Jan 21 – Thu, Feb 4

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

Thu, Jan 21 – Thu, Feb 4

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

Thu, Jan 21 – Thu, Feb 4

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

Thu, Jan 21 – Thu, Feb 4

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

Thu, Jan 21 – Thu, Feb 4

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

Thu, Jan 21 – Thu, Feb 4

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 20, 2026 → Nov 23, 2026Nov 27, 2026 → Dec 4, 2026Nov 20, 2026 · One way
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)
2027-01-21 → 2027-02-04Southwest AirlinesWN958 / WN4918$266.002026-10-29T00:52:52Z
2027-01-21 → 2027-02-04American AirlinesAA4500 / AA3444$275.502026-10-29T00:52:52Z
2027-01-21 → 2027-02-04Frontier Airlines / Southwest AirlinesF93511 + F94473 / WN4918$218.502026-10-29T00:52:52Z
2027-01-21 → 2027-02-04United AirlinesUA1734 + UA4427 / UA4406 + UA1392$256.502026-10-29T00:52:52Z
2027-01-21 → 2027-02-04Delta Air LinesDL2222 + DL2822 / DL2868 + DL1171$266.002026-10-29T00:52:52Z
2027-01-21 → 2027-02-04Southwest AirlinesWN819 / WN4918$266.002026-10-29T00:52:52Z
2027-01-21 → 2027-02-04American AirlinesAA3444 / AA3444$275.502026-10-29T00:52:52Z
2027-01-21 → 2027-02-04Southwest AirlinesWN1888 + WN2730 / WN4918$256.502026-10-29T00:52:52Z
2027-01-21 → 2027-02-04American AirlinesAA1249 + AA2486 / AA3444$261.252026-10-29T00:52:52Z
2027-01-21 → 2027-02-04American AirlinesAA1198 + AA5224 / AA3444$261.252026-10-29T00:52:52Z

2027-01-21 → 2027-02-04 · $266.00

  • Southwest Airlines WN958: BOS 2027-01-21 12:25:00 → STL 2027-01-21 14:30:00; nonstop; 185 minutes. Local airport times.
  • Southwest Airlines WN4918: STL 2027-02-04 10:15:00 → BOS 2027-02-04 13:45:00; nonstop; 150 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $275.50

  • American Airlines AA4500: BOS 2027-01-21 16:14:00 → STL 2027-01-21 18:40:00; nonstop; 206 minutes. Local airport times.
  • American Airlines AA3444: STL 2027-02-04 09:59:00 → BOS 2027-02-04 13:36:00; nonstop; 157 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $218.50

  • Frontier Airlines F93511 / F94473: BOS 2027-01-21 12:15:00 → STL 2027-01-21 17:42:00; 1 stop(s) via ATL; 387 minutes. Local airport times.
    • F93511: BOS 2027-01-21 12:15:00 → ATL 2027-01-21 15:36:00; layover at ATL: 73 minutes.
    • F94473: ATL 2027-01-21 16:49:00 → STL 2027-01-21 17:42:00.
  • Southwest Airlines WN4918: STL 2027-02-04 10:15:00 → BOS 2027-02-04 13:45:00; nonstop; 150 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $256.50

  • United Airlines UA1734 / UA4427: BOS 2027-01-21 05:45:00 → STL 2027-01-21 10:12:00; 1 stop(s) via IAD; 327 minutes. Local airport times.
    • UA1734: BOS 2027-01-21 05:45:00 → IAD 2027-01-21 07:25:00; layover at IAD: 75 minutes.
    • UA4427: IAD 2027-01-21 08:40:00 → STL 2027-01-21 10:12:00.
  • United Airlines UA4406 / UA1392: STL 2027-02-04 08:30:00 → BOS 2027-02-04 14:32:00; 1 stop(s) via IAD; 302 minutes. Local airport times.
    • UA4406: STL 2027-02-04 08:30:00 → IAD 2027-02-04 11:35:00; layover at IAD: 75 minutes.
    • UA1392: IAD 2027-02-04 12:50:00 → BOS 2027-02-04 14:32:00.

2027-01-21 → 2027-02-04 · $266.00

  • Delta Air Lines DL2222 / DL2822: BOS 2027-01-21 13:04:00 → STL 2027-01-21 17:20:00; 1 stop(s) via DTW; 316 minutes. Local airport times.
    • DL2222: BOS 2027-01-21 13:04:00 → DTW 2027-01-21 15:19:00; layover at DTW: 74 minutes.
    • DL2822: DTW 2027-01-21 16:33:00 → STL 2027-01-21 17:20:00.
  • Delta Air Lines DL2868 / DL1171: STL 2027-02-04 10:14:00 → BOS 2027-02-04 16:04:00; 1 stop(s) via DTW; 290 minutes. Local airport times.
    • DL2868: STL 2027-02-04 10:14:00 → DTW 2027-02-04 12:46:00; layover at DTW: 81 minutes.
    • DL1171: DTW 2027-02-04 14:07:00 → BOS 2027-02-04 16:04:00.

2027-01-21 → 2027-02-04 · $266.00

  • Southwest Airlines WN819: BOS 2027-01-21 05:20:00 → STL 2027-01-21 07:30:00; nonstop; 190 minutes. Local airport times.
  • Southwest Airlines WN4918: STL 2027-02-04 10:15:00 → BOS 2027-02-04 13:45:00; nonstop; 150 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $275.50

  • American Airlines AA3444: BOS 2027-01-21 07:00:00 → STL 2027-01-21 09:26:00; nonstop; 206 minutes. Local airport times.
  • American Airlines AA3444: STL 2027-02-04 09:59:00 → BOS 2027-02-04 13:36:00; nonstop; 157 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $256.50

  • Southwest Airlines WN1888 / WN2730: BOS 2027-01-21 13:20:00 → STL 2027-01-21 18:05:00; 1 stop(s) via BWI; 345 minutes. Local airport times.
    • WN1888: BOS 2027-01-21 13:20:00 → BWI 2027-01-21 14:55:00; layover at BWI: 110 minutes.
    • WN2730: BWI 2027-01-21 16:45:00 → STL 2027-01-21 18:05:00.
  • Southwest Airlines WN4918: STL 2027-02-04 10:15:00 → BOS 2027-02-04 13:45:00; nonstop; 150 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $261.25

  • American Airlines AA1249 / AA2486: BOS 2027-01-21 05:00:00 → STL 2027-01-21 10:19:00; 1 stop(s) via CLT; 379 minutes. Local airport times.
    • AA1249: BOS 2027-01-21 05:00:00 → CLT 2027-01-21 07:34:00; layover at CLT: 101 minutes.
    • AA2486: CLT 2027-01-21 09:15:00 → STL 2027-01-21 10:19:00.
  • American Airlines AA3444: STL 2027-02-04 09:59:00 → BOS 2027-02-04 13:36:00; nonstop; 157 minutes. Local airport times.

2027-01-21 → 2027-02-04 · $261.25

  • American Airlines AA1198 / AA5224: BOS 2027-01-21 16:00:00 → STL 2027-01-21 20:31:00; 1 stop(s) via PHL; 331 minutes. Local airport times.
    • AA1198: BOS 2027-01-21 16:00:00 → PHL 2027-01-21 17:40:00; layover at PHL: 60 minutes.
    • AA5224: PHL 2027-01-21 18:40:00 → STL 2027-01-21 20:31:00.
  • American Airlines AA3444: STL 2027-02-04 09:59:00 → BOS 2027-02-04 13:36:00; nonstop; 157 minutes. Local airport times.

More dates for this route