Travel with Axel,
get the best price.

Boston → Saint Louis

Dec 9, 2026 · return Dec 16, 2026

BOS → STL1 adulteconomyRound trip

10 flight options · 5 airlines

Nonstop flights

Wed, Dec 9 – Wed, Dec 16

Southwest Airlines
5:35 amBOS
3h 5m
Nonstop
7:40 amSTL
Southwest Airlines
10:15 amSTL
2h 30m
Nonstop
1:45 pmBOS

Round-trip total · 1 adult · Taxes included

Wed, Dec 9 – Wed, Dec 16

American Airlines
7:00 amBOS
3h 16m
Nonstop
9:16 amSTL
American Airlines
9:59 amSTL
2h 37m
Nonstop
1:36 pmBOS

Round-trip total · 1 adult · Taxes included

Wed, Dec 9 – Wed, Dec 16

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

Wed, Dec 9 – Wed, Dec 16

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

Wed, Dec 9 – Wed, Dec 16

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

Wed, Dec 9 – Wed, Dec 16

United Airlines
5:45 amBOS
5h 27m
IAD · 1h 15m
10:12 amSTL
United Airlines
6:00 amSTL
5h 27m
EWR · 1h 55m
12:27 pmBOS

Round-trip total · 1 adult · Taxes included

Wed, Dec 9 – Wed, Dec 16

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

Wed, Dec 9 – Wed, Dec 16

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

Wed, Dec 9 – Wed, Dec 16

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

Wed, Dec 9 – Wed, Dec 16

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

Make this trip yours

BOS ⇄ STL

Economy

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

No account needed to see prices.

Already have an account? Log in

Why book with Axel
  • A real airline bookingThe booking is in the airline’s own system under your name. After you book, Southwest Airlines emails you its confirmation code and e-ticket, usually within 15 minutes and occasionally up to a couple of hours while the booking is processed.
  • Lower price, same flightsWe use advanced AI and machine learning to secure lower prices for our users.
  • Not satisfied? Full refund.If you are unhappy with the experience for any reason, or simply change your mind, cancel within 24 hours of booking (departure 7+ days away) and we refund you in full. We stand by our product. Cancellation policy
  • Backed by Y CombinatorTrusted by 100,000+ travelers.

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

More dates

All dates for this routeOct 30, 2026 → Nov 2, 2026Oct 31, 2026 → Nov 7, 2026Nov 13, 2026 → Nov 16, 2026Nov 14, 2026 → Nov 21, 2026Nov 24, 2026 → Nov 29, 2026Nov 27, 2026 → Nov 30, 2026Nov 28, 2026 → Dec 5, 2026Dec 11, 2026 → Dec 14, 2026Dec 12, 2026 → Dec 19, 2026Dec 22, 2026 → Dec 27, 2026Dec 25, 2026 → Dec 28, 2026Dec 26, 2026 → Jan 2, 2027Dec 30, 2026 → Jan 2, 2027Jan 8, 2027 → Jan 11, 2027Jan 9, 2027 → Jan 16, 2027Jan 15, 2027 → Jan 18, 2027Jan 22, 2027 → Jan 25, 2027Jan 23, 2027 → Jan 30, 2027Feb 5, 2027 → Feb 8, 2027Feb 6, 2027 → Feb 13, 2027Feb 12, 2027 → Feb 15, 2027Mar 5, 2027 → Mar 8, 2027Mar 6, 2027 → Mar 13, 2027Mar 25, 2027 → Mar 29, 2027Apr 2, 2027 → Apr 5, 2027Apr 3, 2027 → Apr 10, 2027Apr 30, 2027 → May 3, 2027May 1, 2027 → May 8, 2027May 28, 2027 → May 31, 2027May 29, 2027 → Jun 5, 2027Jun 25, 2027 → Jun 28, 2027Jun 26, 2027 → Jul 3, 2027Jul 2, 2027 → Jul 6, 2027Jul 23, 2027 → Jul 26, 2027Jul 24, 2027 → Jul 31, 2027Aug 20, 2027 → Aug 23, 2027Aug 21, 2027 → Aug 28, 2027Sep 3, 2027 → Sep 6, 2027Sep 17, 2027 → Sep 20, 2027Oct 30, 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)
2026-12-09 → 2026-12-16Southwest AirlinesWN819 / WN4918$280.002026-10-29T00:52:52Z
2026-12-09 → 2026-12-16American AirlinesAA3444 / AA3444$290.002026-10-29T00:52:52Z
2026-12-09 → 2026-12-16Frontier Airlines / Southwest AirlinesF93511 + F94473 / WN4918$230.002026-10-29T00:52:52Z
2026-12-09 → 2026-12-16United AirlinesUA1734 + UA4427 / UA1344 + UA1669$270.002026-10-29T00:52:52Z
2026-12-09 → 2026-12-16Delta Air LinesDL2222 + DL2822 / DL2868 + DL1171$280.002026-10-29T00:52:52Z
2026-12-09 → 2026-12-16Southwest AirlinesWN958 / WN4918$280.002026-10-29T00:52:52Z
2026-12-09 → 2026-12-16American AirlinesAA4678 / AA3444$290.002026-10-29T00:52:52Z
2026-12-09 → 2026-12-16Southwest AirlinesWN1888 + WN2730 / WN4918$270.002026-10-29T00:52:52Z
2026-12-09 → 2026-12-16American AirlinesAA1198 + AA5224 / AA3444$275.002026-10-29T00:52:52Z
2026-12-09 → 2026-12-16American AirlinesAA1249 + AA2486 / AA3444$275.002026-10-29T00:52:52Z

2026-12-09 → 2026-12-16 · $280.00

  • Southwest Airlines WN819: BOS 2026-12-09 05:35:00 → STL 2026-12-09 07:40:00; nonstop; 185 minutes. Local airport times.
  • Southwest Airlines WN4918: STL 2026-12-16 10:15:00 → BOS 2026-12-16 13:45:00; nonstop; 150 minutes. Local airport times.

2026-12-09 → 2026-12-16 · $290.00

  • American Airlines AA3444: BOS 2026-12-09 07:00:00 → STL 2026-12-09 09:16:00; nonstop; 196 minutes. Local airport times.
  • American Airlines AA3444: STL 2026-12-16 09:59:00 → BOS 2026-12-16 13:36:00; nonstop; 157 minutes. Local airport times.

2026-12-09 → 2026-12-16 · $230.00

  • Frontier Airlines F93511 / F94473: BOS 2026-12-09 12:15:00 → STL 2026-12-09 17:42:00; 1 stop(s) via ATL; 387 minutes. Local airport times.
    • F93511: BOS 2026-12-09 12:15:00 → ATL 2026-12-09 15:36:00; layover at ATL: 73 minutes.
    • F94473: ATL 2026-12-09 16:49:00 → STL 2026-12-09 17:42:00.
  • Southwest Airlines WN4918: STL 2026-12-16 10:15:00 → BOS 2026-12-16 13:45:00; nonstop; 150 minutes. Local airport times.

2026-12-09 → 2026-12-16 · $270.00

  • United Airlines UA1734 / UA4427: BOS 2026-12-09 05:45:00 → STL 2026-12-09 10:12:00; 1 stop(s) via IAD; 327 minutes. Local airport times.
    • UA1734: BOS 2026-12-09 05:45:00 → IAD 2026-12-09 07:25:00; layover at IAD: 75 minutes.
    • UA4427: IAD 2026-12-09 08:40:00 → STL 2026-12-09 10:12:00.
  • United Airlines UA1344 / UA1669: STL 2026-12-16 06:00:00 → BOS 2026-12-16 12:27:00; 1 stop(s) via EWR; 327 minutes. Local airport times.
    • UA1344: STL 2026-12-16 06:00:00 → EWR 2026-12-16 09:21:00; layover at EWR: 115 minutes.
    • UA1669: EWR 2026-12-16 11:16:00 → BOS 2026-12-16 12:27:00.

2026-12-09 → 2026-12-16 · $280.00

  • Delta Air Lines DL2222 / DL2822: BOS 2026-12-09 13:04:00 → STL 2026-12-09 17:20:00; 1 stop(s) via DTW; 316 minutes. Local airport times.
    • DL2222: BOS 2026-12-09 13:04:00 → DTW 2026-12-09 15:19:00; layover at DTW: 74 minutes.
    • DL2822: DTW 2026-12-09 16:33:00 → STL 2026-12-09 17:20:00.
  • Delta Air Lines DL2868 / DL1171: STL 2026-12-16 10:14:00 → BOS 2026-12-16 16:04:00; 1 stop(s) via DTW; 290 minutes. Local airport times.
    • DL2868: STL 2026-12-16 10:14:00 → DTW 2026-12-16 12:46:00; layover at DTW: 81 minutes.
    • DL1171: DTW 2026-12-16 14:07:00 → BOS 2026-12-16 16:04:00.

2026-12-09 → 2026-12-16 · $280.00

  • Southwest Airlines WN958: BOS 2026-12-09 12:25:00 → STL 2026-12-09 14:30:00; nonstop; 185 minutes. Local airport times.
  • Southwest Airlines WN4918: STL 2026-12-16 10:15:00 → BOS 2026-12-16 13:45:00; nonstop; 150 minutes. Local airport times.

2026-12-09 → 2026-12-16 · $290.00

  • American Airlines AA4678: BOS 2026-12-09 15:25:00 → STL 2026-12-09 17:47:00; nonstop; 202 minutes. Local airport times.
  • American Airlines AA3444: STL 2026-12-16 09:59:00 → BOS 2026-12-16 13:36:00; nonstop; 157 minutes. Local airport times.

2026-12-09 → 2026-12-16 · $270.00

  • Southwest Airlines WN1888 / WN2730: BOS 2026-12-09 13:20:00 → STL 2026-12-09 18:05:00; 1 stop(s) via BWI; 345 minutes. Local airport times.
    • WN1888: BOS 2026-12-09 13:20:00 → BWI 2026-12-09 14:55:00; layover at BWI: 110 minutes.
    • WN2730: BWI 2026-12-09 16:45:00 → STL 2026-12-09 18:05:00.
  • Southwest Airlines WN4918: STL 2026-12-16 10:15:00 → BOS 2026-12-16 13:45:00; nonstop; 150 minutes. Local airport times.

2026-12-09 → 2026-12-16 · $275.00

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

2026-12-09 → 2026-12-16 · $275.00

  • American Airlines AA1249 / AA2486: BOS 2026-12-09 05:00:00 → STL 2026-12-09 10:19:00; 1 stop(s) via CLT; 379 minutes. Local airport times.
    • AA1249: BOS 2026-12-09 05:00:00 → CLT 2026-12-09 07:34:00; layover at CLT: 101 minutes.
    • AA2486: CLT 2026-12-09 09:15:00 → STL 2026-12-09 10:19:00.
  • American Airlines AA3444: STL 2026-12-16 09:59:00 → BOS 2026-12-16 13:36:00; nonstop; 157 minutes. Local airport times.

More dates for this route