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

Philadelphia → Saint Louis

Dec 28, 2026 · return Dec 31, 2026

PHL → STL1 adulteconomyRound trip

10 flight options · 5 airlines

Nonstop flights

Mon, Dec 28 – Thu, Dec 31

Southwest Airlines
5:25 amPHL
2h 30m
Nonstop
6:55 amSTL
Southwest Airlines
7:55 pmSTL
2h 10m
Nonstop
11:05 pmPHL

Round-trip total · 1 adult · Taxes included

Mon, Dec 28 – Thu, Dec 31

American Airlines
8:55 pmPHL
2h 47m
Nonstop
10:42 pmSTL
American Airlines
1:17 pmSTL
2h 16m
Nonstop
4:33 pmPHL

Round-trip total · 1 adult · Taxes included

Mon, Dec 28 – Thu, Dec 31

Southwest Airlines
6:00 amPHL
2h 45m
Nonstop
7:45 amSTL
Southwest Airlines
10:40 amSTL
2h 10m
Nonstop
1:50 pmPHL

Round-trip total · 1 adult · Taxes included

Mon, Dec 28 – Thu, Dec 31

American Airlines
10:19 amPHL
2h 44m
Nonstop
12:03 pmSTL
American Airlines
1:17 pmSTL
2h 16m
Nonstop
4:33 pmPHL

Round-trip total · 1 adult · Taxes included

One-stop flights

Mon, Dec 28 – Thu, Dec 31

Frontier Airlines
12:49 pmPHL
5h 53m
ATL · 1h 30m
5:42 pmSTL
Frontier Airlines
12:02 pmSTL
5h 30m
ATL · 1h 42m
6:32 pmPHL

Round-trip total · 1 adult · Taxes included

Mon, Dec 28 – Thu, Dec 31

United Airlines
3:05 pmPHL
5h 30m
IAD · 1h 42m
7:35 pmSTL
United Airlines
1:23 pmSTL
4h 39m
IAD · 1h 17m
7:02 pmPHL

Round-trip total · 1 adult · Taxes included

Mon, Dec 28 – Thu, Dec 31

Delta Air Lines
9:43 amPHL
4h 47m
DTW · 1h 8m
1:30 pmSTL
Delta Air Lines
10:14 amSTL
5h 21m
DTW · 2h 13m
4:35 pmPHL

Round-trip total · 1 adult · Taxes included

Mon, Dec 28 – Thu, Dec 31

Southwest Airlines
7:30 amPHL
6h 10m
MDW · 2h 40m
12:40 pmSTL
Southwest Airlines
7:55 pmSTL
2h 10m
Nonstop
11:05 pmPHL

Round-trip total · 1 adult · Taxes included

Mon, Dec 28 – Thu, Dec 31

American Airlines
3:06 pmPHL
5h 24m
CLT · 1h 23m
7:30 pmSTL
American Airlines
1:17 pmSTL
2h 16m
Nonstop
4:33 pmPHL

Round-trip total · 1 adult · Taxes included

Mon, Dec 28 – Thu, Dec 31

American Airlines
7:35 amPHL
6h 7m
BOS · 1h 15m
12:42 pmSTL
American Airlines
1:17 pmSTL
2h 16m
Nonstop
4:33 pmPHL

Round-trip total · 1 adult · Taxes included

Make this trip yours

PHL ⇄ 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 27, 2026 → Dec 30, 2026Dec 29, 2026 → Jan 1, 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.

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: Philadelphia to Saint Louis (STL) flight deals

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-28 → 2026-12-31Southwest AirlinesWN3375 / WN4923$390.002026-10-29T01:56:03Z
2026-12-28 → 2026-12-31American AirlinesAA5536 / AA5477$442.002026-10-29T01:56:03Z
2026-12-28 → 2026-12-31Frontier AirlinesF91147 + F94473 / F94474 + F92298$234.002026-10-29T01:56:03Z
2026-12-28 → 2026-12-31United AirlinesUA4575 + UA4527 / UA3495 + UA4405$403.002026-10-29T01:56:03Z
2026-12-28 → 2026-12-31Delta Air LinesDL2968 + DL1371 / DL2868 + DL1391$416.002026-10-29T01:56:03Z
2026-12-28 → 2026-12-31Southwest AirlinesWN3375 / WN4922$390.002026-10-29T01:56:03Z
2026-12-28 → 2026-12-31American AirlinesAA5105 / AA5477$442.002026-10-29T01:56:03Z
2026-12-28 → 2026-12-31Southwest AirlinesWN3372 + WN2737 / WN4923$377.002026-10-29T01:56:03Z
2026-12-28 → 2026-12-31American AirlinesAA567 + AA2937 / AA5477$416.002026-10-29T01:56:03Z
2026-12-28 → 2026-12-31American AirlinesAA3308 + AA4341 / AA5477$416.002026-10-29T01:56:03Z

2026-12-28 → 2026-12-31 · $390.00

  • Southwest Airlines WN3375: PHL 2026-12-28 05:25:00 → STL 2026-12-28 06:55:00; nonstop; 150 minutes. Local airport times.
  • Southwest Airlines WN4923: STL 2026-12-31 19:55:00 → PHL 2026-12-31 23:05:00; nonstop; 130 minutes. Local airport times.

2026-12-28 → 2026-12-31 · $442.00

  • American Airlines AA5536: PHL 2026-12-28 20:55:00 → STL 2026-12-28 22:42:00; nonstop; 167 minutes. Local airport times.
  • American Airlines AA5477: STL 2026-12-31 13:17:00 → PHL 2026-12-31 16:33:00; nonstop; 136 minutes. Local airport times.

2026-12-28 → 2026-12-31 · $234.00

  • Frontier Airlines F91147 / F94473: PHL 2026-12-28 12:49:00 → STL 2026-12-28 17:42:00; 1 stop(s) via ATL; 353 minutes. Local airport times.
    • F91147: PHL 2026-12-28 12:49:00 → ATL 2026-12-28 15:19:00; layover at ATL: 90 minutes.
    • F94473: ATL 2026-12-28 16:49:00 → STL 2026-12-28 17:42:00.
  • Frontier Airlines F94474 / F92298: STL 2026-12-31 12:02:00 → PHL 2026-12-31 18:32:00; 1 stop(s) via ATL; 330 minutes. Local airport times.
    • F94474: STL 2026-12-31 12:02:00 → ATL 2026-12-31 14:42:00; layover at ATL: 102 minutes.
    • F92298: ATL 2026-12-31 16:24:00 → PHL 2026-12-31 18:32:00.

2026-12-28 → 2026-12-31 · $403.00

  • United Airlines UA4575 / UA4527: PHL 2026-12-28 15:05:00 → STL 2026-12-28 19:35:00; 1 stop(s) via IAD; 330 minutes. Local airport times.
    • UA4575: PHL 2026-12-28 15:05:00 → IAD 2026-12-28 16:18:00; layover at IAD: 102 minutes.
    • UA4527: IAD 2026-12-28 18:00:00 → STL 2026-12-28 19:35:00.
  • United Airlines UA3495 / UA4405: STL 2026-12-31 13:23:00 → PHL 2026-12-31 19:02:00; 1 stop(s) via IAD; 279 minutes. Local airport times.
    • UA3495: STL 2026-12-31 13:23:00 → IAD 2026-12-31 16:33:00; layover at IAD: 77 minutes.
    • UA4405: IAD 2026-12-31 17:50:00 → PHL 2026-12-31 19:02:00.

2026-12-28 → 2026-12-31 · $416.00

  • Delta Air Lines DL2968 / DL1371: PHL 2026-12-28 09:43:00 → STL 2026-12-28 13:30:00; 1 stop(s) via DTW; 287 minutes. Local airport times.
    • DL2968: PHL 2026-12-28 09:43:00 → DTW 2026-12-28 11:35:00; layover at DTW: 68 minutes.
    • DL1371: DTW 2026-12-28 12:43:00 → STL 2026-12-28 13:30:00.
  • Delta Air Lines DL2868 / DL1391: STL 2026-12-31 10:14:00 → PHL 2026-12-31 16:35:00; 1 stop(s) via DTW; 321 minutes. Local airport times.
    • DL2868: STL 2026-12-31 10:14:00 → DTW 2026-12-31 12:46:00; layover at DTW: 133 minutes.
    • DL1391: DTW 2026-12-31 14:59:00 → PHL 2026-12-31 16:35:00.

2026-12-28 → 2026-12-31 · $390.00

  • Southwest Airlines WN3375: PHL 2026-12-28 06:00:00 → STL 2026-12-28 07:45:00; nonstop; 165 minutes. Local airport times.
  • Southwest Airlines WN4922: STL 2026-12-31 10:40:00 → PHL 2026-12-31 13:50:00; nonstop; 130 minutes. Local airport times.

2026-12-28 → 2026-12-31 · $442.00

  • American Airlines AA5105: PHL 2026-12-28 10:19:00 → STL 2026-12-28 12:03:00; nonstop; 164 minutes. Local airport times.
  • American Airlines AA5477: STL 2026-12-31 13:17:00 → PHL 2026-12-31 16:33:00; nonstop; 136 minutes. Local airport times.

2026-12-28 → 2026-12-31 · $377.00

  • Southwest Airlines WN3372 / WN2737: PHL 2026-12-28 07:30:00 → STL 2026-12-28 12:40:00; 1 stop(s) via MDW; 370 minutes. Local airport times.
    • WN3372: PHL 2026-12-28 07:30:00 → MDW 2026-12-28 08:50:00; layover at MDW: 160 minutes.
    • WN2737: MDW 2026-12-28 11:30:00 → STL 2026-12-28 12:40:00.
  • Southwest Airlines WN4923: STL 2026-12-31 19:55:00 → PHL 2026-12-31 23:05:00; nonstop; 130 minutes. Local airport times.

2026-12-28 → 2026-12-31 · $416.00

  • American Airlines AA567 / AA2937: PHL 2026-12-28 15:06:00 → STL 2026-12-28 19:30:00; 1 stop(s) via CLT; 324 minutes. Local airport times.
    • AA567: PHL 2026-12-28 15:06:00 → CLT 2026-12-28 17:04:00; layover at CLT: 83 minutes.
    • AA2937: CLT 2026-12-28 18:27:00 → STL 2026-12-28 19:30:00.
  • American Airlines AA5477: STL 2026-12-31 13:17:00 → PHL 2026-12-31 16:33:00; nonstop; 136 minutes. Local airport times.

2026-12-28 → 2026-12-31 · $416.00

  • American Airlines AA3308 / AA4341: PHL 2026-12-28 07:35:00 → STL 2026-12-28 12:42:00; 1 stop(s) via BOS; 367 minutes. Local airport times.
    • AA3308: PHL 2026-12-28 07:35:00 → BOS 2026-12-28 09:04:00; layover at BOS: 75 minutes.
    • AA4341: BOS 2026-12-28 10:19:00 → STL 2026-12-28 12:42:00.
  • American Airlines AA5477: STL 2026-12-31 13:17:00 → PHL 2026-12-31 16:33:00; nonstop; 136 minutes. Local airport times.

Explore this route

For AI assistants

  • This page: Philadelphia (PHL) to Saint Louis (STL) · Dec 28, 2026 · return Dec 31, 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.
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  • 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 Philadelphia 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.