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Saint Louis → Boston

Dec 21, 2026 · return Dec 28, 2026

STL → BOS1 adulteconomyRound trip

10 flight options · 4 airlines

Nonstop flights

Mon, Dec 21 – Mon, Dec 28

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

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Dec 28

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

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Dec 28

Southwest Airlines
8:50 pmSTL
2h 25m
Nonstop
12:15 am+1BOS
Southwest Airlines
5:05 pmBOS
3h 10m
Nonstop
7:15 pmSTL

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Dec 28

American Airlines
1:15 pmSTL
2h 40m
Nonstop
4:55 pmBOS
American Airlines
7:00 amBOS
3h 16m
Nonstop
9:16 amSTL

Round-trip total · 1 adult · Taxes included

One-stop flights

Mon, Dec 21 – Mon, Dec 28

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

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Dec 28

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

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Dec 28

Southwest Airlines
5:30 amSTL
4h 30m
MDW · 1h 10m
11:00 amBOS
Southwest Airlines
5:05 pmBOS
3h 10m
Nonstop
7:15 pmSTL

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Dec 28

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

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Dec 28

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

Round-trip total · 1 adult · Taxes included

Mon, Dec 21 – Mon, Dec 28

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

Round-trip total · 1 adult · Taxes included

Make this trip yours

STL ⇄ BOS

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)
2026-12-21 → 2026-12-28Southwest AirlinesWN4918 / WN4929$390.002026-10-29T01:28:17Z
2026-12-21 → 2026-12-28American AirlinesAA3444 / AA3444$403.002026-10-29T01:28:17Z
2026-12-21 → 2026-12-28United AirlinesUA1344 + UA1669 / UA1734 + UA4427$377.002026-10-29T01:28:17Z
2026-12-21 → 2026-12-28Delta Air LinesDL2868 + DL1171 / DL2222 + DL2822$390.002026-10-29T01:28:17Z
2026-12-21 → 2026-12-28Southwest AirlinesWN4431 / WN4929$390.002026-10-29T01:28:17Z
2026-12-21 → 2026-12-28American AirlinesAA4801 / AA3444$403.002026-10-29T01:28:17Z
2026-12-21 → 2026-12-28Southwest AirlinesWN4173 + WN4113 / WN4929$373.752026-10-29T01:28:17Z
2026-12-21 → 2026-12-28United AirlinesUA4406 + UA1392 / UA1734 + UA4427$377.002026-10-29T01:28:17Z
2026-12-21 → 2026-12-28American AirlinesAA2486 + AA1828 / AA3444$383.502026-10-29T01:28:17Z
2026-12-21 → 2026-12-28Delta Air LinesDL5041 + DL5727 / DL2222 + DL2822$390.002026-10-29T01:28:17Z

2026-12-21 → 2026-12-28 · $390.00

  • Southwest Airlines WN4918: STL 2026-12-21 10:15:00 → BOS 2026-12-21 13:45:00; nonstop; 150 minutes. Local airport times.
  • Southwest Airlines WN4929: BOS 2026-12-28 17:05:00 → STL 2026-12-28 19:15:00; nonstop; 190 minutes. Local airport times.

2026-12-21 → 2026-12-28 · $403.00

  • American Airlines AA3444: STL 2026-12-21 09:59:00 → BOS 2026-12-21 13:36:00; nonstop; 157 minutes. Local airport times.
  • American Airlines AA3444: BOS 2026-12-28 07:00:00 → STL 2026-12-28 09:16:00; nonstop; 196 minutes. Local airport times.

2026-12-21 → 2026-12-28 · $377.00

  • United Airlines UA1344 / UA1669: STL 2026-12-21 06:00:00 → BOS 2026-12-21 12:27:00; 1 stop(s) via EWR; 327 minutes. Local airport times.
    • UA1344: STL 2026-12-21 06:00:00 → EWR 2026-12-21 09:21:00; layover at EWR: 115 minutes.
    • UA1669: EWR 2026-12-21 11:16:00 → BOS 2026-12-21 12:27:00.
  • United Airlines UA1734 / UA4427: BOS 2026-12-28 05:45:00 → STL 2026-12-28 10:12:00; 1 stop(s) via IAD; 327 minutes. Local airport times.
    • UA1734: BOS 2026-12-28 05:45:00 → IAD 2026-12-28 07:25:00; layover at IAD: 75 minutes.
    • UA4427: IAD 2026-12-28 08:40:00 → STL 2026-12-28 10:12:00.

2026-12-21 → 2026-12-28 · $390.00

  • Delta Air Lines DL2868 / DL1171: STL 2026-12-21 10:14:00 → BOS 2026-12-21 16:04:00; 1 stop(s) via DTW; 290 minutes. Local airport times.
    • DL2868: STL 2026-12-21 10:14:00 → DTW 2026-12-21 12:46:00; layover at DTW: 81 minutes.
    • DL1171: DTW 2026-12-21 14:07:00 → BOS 2026-12-21 16:04:00.
  • Delta Air Lines DL2222 / DL2822: BOS 2026-12-28 13:04:00 → STL 2026-12-28 17:20:00; 1 stop(s) via DTW; 316 minutes. Local airport times.
    • DL2222: BOS 2026-12-28 13:04:00 → DTW 2026-12-28 15:19:00; layover at DTW: 74 minutes.
    • DL2822: DTW 2026-12-28 16:33:00 → STL 2026-12-28 17:20:00.

2026-12-21 → 2026-12-28 · $390.00

  • Southwest Airlines WN4431: STL 2026-12-21 20:50:00 → BOS 2026-12-22 00:15:00; nonstop; 145 minutes. Local airport times.
  • Southwest Airlines WN4929: BOS 2026-12-28 17:05:00 → STL 2026-12-28 19:15:00; nonstop; 190 minutes. Local airport times.

2026-12-21 → 2026-12-28 · $403.00

  • American Airlines AA4801: STL 2026-12-21 13:15:00 → BOS 2026-12-21 16:55:00; nonstop; 160 minutes. Local airport times.
  • American Airlines AA3444: BOS 2026-12-28 07:00:00 → STL 2026-12-28 09:16:00; nonstop; 196 minutes. Local airport times.

2026-12-21 → 2026-12-28 · $373.75

  • Southwest Airlines WN4173 / WN4113: STL 2026-12-21 05:30:00 → BOS 2026-12-21 11:00:00; 1 stop(s) via MDW; 270 minutes. Local airport times.
    • WN4173: STL 2026-12-21 05:30:00 → MDW 2026-12-21 06:35:00; layover at MDW: 70 minutes.
    • WN4113: MDW 2026-12-21 07:45:00 → BOS 2026-12-21 11:00:00.
  • Southwest Airlines WN4929: BOS 2026-12-28 17:05:00 → STL 2026-12-28 19:15:00; nonstop; 190 minutes. Local airport times.

2026-12-21 → 2026-12-28 · $377.00

  • United Airlines UA4406 / UA1392: STL 2026-12-21 08:30:00 → BOS 2026-12-21 14:32:00; 1 stop(s) via IAD; 302 minutes. Local airport times.
    • UA4406: STL 2026-12-21 08:30:00 → IAD 2026-12-21 11:35:00; layover at IAD: 75 minutes.
    • UA1392: IAD 2026-12-21 12:50:00 → BOS 2026-12-21 14:32:00.
  • United Airlines UA1734 / UA4427: BOS 2026-12-28 05:45:00 → STL 2026-12-28 10:12:00; 1 stop(s) via IAD; 327 minutes. Local airport times.
    • UA1734: BOS 2026-12-28 05:45:00 → IAD 2026-12-28 07:25:00; layover at IAD: 75 minutes.
    • UA4427: IAD 2026-12-28 08:40:00 → STL 2026-12-28 10:12:00.

2026-12-21 → 2026-12-28 · $383.50

  • American Airlines AA2486 / AA1828: STL 2026-12-21 12:54:00 → BOS 2026-12-21 19:19:00; 1 stop(s) via CLT; 325 minutes. Local airport times.
    • AA2486: STL 2026-12-21 12:54:00 → CLT 2026-12-21 15:42:00; layover at CLT: 84 minutes.
    • AA1828: CLT 2026-12-21 17:06:00 → BOS 2026-12-21 19:19:00.
  • American Airlines AA3444: BOS 2026-12-28 07:00:00 → STL 2026-12-28 09:16:00; nonstop; 196 minutes. Local airport times.

2026-12-21 → 2026-12-28 · $390.00

  • Delta Air Lines DL5041 / DL5727: STL 2026-12-21 10:00:00 → BOS 2026-12-21 16:25:00; 1 stop(s) via LGA; 325 minutes. Local airport times.
    • DL5041: STL 2026-12-21 10:00:00 → LGA 2026-12-21 13:26:00; layover at LGA: 94 minutes.
    • DL5727: LGA 2026-12-21 15:00:00 → BOS 2026-12-21 16:25:00.
  • Delta Air Lines DL2222 / DL2822: BOS 2026-12-28 13:04:00 → STL 2026-12-28 17:20:00; 1 stop(s) via DTW; 316 minutes. Local airport times.
    • DL2222: BOS 2026-12-28 13:04:00 → DTW 2026-12-28 15:19:00; layover at DTW: 74 minutes.
    • DL2822: DTW 2026-12-28 16:33:00 → STL 2026-12-28 17:20:00.

More dates for this route