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

Saint Louis → Philadelphia

Dec 20, 2026 · return Dec 24, 2026

STL → PHL1 adulteconomyRound trip

10 flight options · 5 airlines

Nonstop flights

Sun, Dec 20 – Thu, Dec 24

Southwest Airlines
10:40 amSTL
2h 10m
Nonstop
1:50 pmPHL
Southwest Airlines
2:45 pmPHL
2h 35m
Nonstop
4:20 pmSTL

Round-trip total · 1 adult · Taxes included

Sun, Dec 20 – Thu, Dec 24

American Airlines
12:19 pmSTL
2h 13m
Nonstop
3:32 pmPHL
American Airlines
8:55 pmPHL
2h 47m
Nonstop
10:42 pmSTL

Round-trip total · 1 adult · Taxes included

Sun, Dec 20 – Thu, Dec 24

Southwest Airlines
7:55 pmSTL
2h 10m
Nonstop
11:05 pmPHL
Southwest Airlines
2:45 pmPHL
2h 35m
Nonstop
4:20 pmSTL

Round-trip total · 1 adult · Taxes included

Sun, Dec 20 – Thu, Dec 24

American Airlines
6:02 amSTL
2h 15m
Nonstop
9:17 amPHL
American Airlines
8:55 pmPHL
2h 47m
Nonstop
10:42 pmSTL

Round-trip total · 1 adult · Taxes included

One-stop flights

Sun, Dec 20 – Thu, Dec 24

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

Round-trip total · 1 adult · Taxes included

Sun, Dec 20 – Thu, Dec 24

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

Round-trip total · 1 adult · Taxes included

Sun, Dec 20 – Thu, Dec 24

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

Round-trip total · 1 adult · Taxes included

Sun, Dec 20 – Thu, Dec 24

Southwest Airlines
5:30 amSTL
4h 15m
MDW · 1h 10m
10:45 amPHL
Southwest Airlines
2:45 pmPHL
2h 35m
Nonstop
4:20 pmSTL

Round-trip total · 1 adult · Taxes included

Sun, Dec 20 – Thu, Dec 24

Southwest Airlines
8:10 pmSTL
2h 10m
Nonstop
11:20 pmPHL
Southwest Airlines
7:30 amPHL
6h 10m
MDW · 2h 40m
12:40 pmSTL

Round-trip total · 1 adult · Taxes included

Sun, Dec 20 – Thu, Dec 24

American Airlines
12:49 pmSTL
2h 13m
Nonstop
4:02 pmPHL
American Airlines
7:35 amPHL
6h 7m
BOS · 1h 15m
12:42 pmSTL

Round-trip total · 1 adult · Taxes included

Make this trip yours

STL ⇄ PHL

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 19, 2026 → Dec 23, 2026Dec 21, 2026 → Dec 25, 2026
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: Saint Louis to Philadelphia (PHL) flight deals

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-20 → 2026-12-24Southwest AirlinesWN4922 / WN1424$412.502026-10-29T01:28:56Z
2026-12-20 → 2026-12-24American AirlinesAA5105 / AA5536$437.502026-10-29T01:28:56Z
2026-12-20 → 2026-12-24Frontier AirlinesF94474 + F92298 / F91147 + F94473$243.762026-10-29T01:28:56Z
2026-12-20 → 2026-12-24United AirlinesUA3495 + UA4405 / UA4575 + UA4527$406.262026-10-29T01:28:56Z
2026-12-20 → 2026-12-24Delta Air LinesDL2868 + DL1391 / DL2968 + DL1371$412.502026-10-29T01:28:56Z
2026-12-20 → 2026-12-24Southwest AirlinesWN4923 / WN1424$412.502026-10-29T01:28:56Z
2026-12-20 → 2026-12-24American AirlinesAA5450 / AA5536$437.502026-10-29T01:28:56Z
2026-12-20 → 2026-12-24Southwest AirlinesWN4173 + WN1082 / WN1424$384.382026-10-29T01:28:56Z
2026-12-20 → 2026-12-24Southwest AirlinesWN4923 / WN3372 + WN2737$384.382026-10-29T01:28:56Z
2026-12-20 → 2026-12-24American AirlinesAA5105 / AA3308 + AA4341$409.382026-10-29T01:28:56Z

2026-12-20 → 2026-12-24 · $412.50

  • Southwest Airlines WN4922: STL 2026-12-20 10:40:00 → PHL 2026-12-20 13:50:00; nonstop; 130 minutes. Local airport times.
  • Southwest Airlines WN1424: PHL 2026-12-24 14:45:00 → STL 2026-12-24 16:20:00; nonstop; 155 minutes. Local airport times.

2026-12-20 → 2026-12-24 · $437.50

  • American Airlines AA5105: STL 2026-12-20 12:19:00 → PHL 2026-12-20 15:32:00; nonstop; 133 minutes. Local airport times.
  • American Airlines AA5536: PHL 2026-12-24 20:55:00 → STL 2026-12-24 22:42:00; nonstop; 167 minutes. Local airport times.

2026-12-20 → 2026-12-24 · $243.76

  • Frontier Airlines F94474 / F92298: STL 2026-12-20 12:02:00 → PHL 2026-12-20 18:32:00; 1 stop(s) via ATL; 330 minutes. Local airport times.
    • F94474: STL 2026-12-20 12:02:00 → ATL 2026-12-20 14:42:00; layover at ATL: 102 minutes.
    • F92298: ATL 2026-12-20 16:24:00 → PHL 2026-12-20 18:32:00.
  • Frontier Airlines F91147 / F94473: PHL 2026-12-24 12:49:00 → STL 2026-12-24 17:42:00; 1 stop(s) via ATL; 353 minutes. Local airport times.
    • F91147: PHL 2026-12-24 12:49:00 → ATL 2026-12-24 15:19:00; layover at ATL: 90 minutes.
    • F94473: ATL 2026-12-24 16:49:00 → STL 2026-12-24 17:42:00.

2026-12-20 → 2026-12-24 · $406.26

  • United Airlines UA3495 / UA4405: STL 2026-12-20 13:23:00 → PHL 2026-12-20 19:02:00; 1 stop(s) via IAD; 279 minutes. Local airport times.
    • UA3495: STL 2026-12-20 13:23:00 → IAD 2026-12-20 16:33:00; layover at IAD: 77 minutes.
    • UA4405: IAD 2026-12-20 17:50:00 → PHL 2026-12-20 19:02:00.
  • United Airlines UA4575 / UA4527: PHL 2026-12-24 15:05:00 → STL 2026-12-24 19:35:00; 1 stop(s) via IAD; 330 minutes. Local airport times.
    • UA4575: PHL 2026-12-24 15:05:00 → IAD 2026-12-24 16:18:00; layover at IAD: 102 minutes.
    • UA4527: IAD 2026-12-24 18:00:00 → STL 2026-12-24 19:35:00.

2026-12-20 → 2026-12-24 · $412.50

  • Delta Air Lines DL2868 / DL1391: STL 2026-12-20 10:14:00 → PHL 2026-12-20 16:35:00; 1 stop(s) via DTW; 321 minutes. Local airport times.
    • DL2868: STL 2026-12-20 10:14:00 → DTW 2026-12-20 12:46:00; layover at DTW: 133 minutes.
    • DL1391: DTW 2026-12-20 14:59:00 → PHL 2026-12-20 16:35:00.
  • Delta Air Lines DL2968 / DL1371: PHL 2026-12-24 09:43:00 → STL 2026-12-24 13:30:00; 1 stop(s) via DTW; 287 minutes. Local airport times.
    • DL2968: PHL 2026-12-24 09:43:00 → DTW 2026-12-24 11:35:00; layover at DTW: 68 minutes.
    • DL1371: DTW 2026-12-24 12:43:00 → STL 2026-12-24 13:30:00.

2026-12-20 → 2026-12-24 · $412.50

  • Southwest Airlines WN4923: STL 2026-12-20 19:55:00 → PHL 2026-12-20 23:05:00; nonstop; 130 minutes. Local airport times.
  • Southwest Airlines WN1424: PHL 2026-12-24 14:45:00 → STL 2026-12-24 16:20:00; nonstop; 155 minutes. Local airport times.

2026-12-20 → 2026-12-24 · $437.50

  • American Airlines AA5450: STL 2026-12-20 06:02:00 → PHL 2026-12-20 09:17:00; nonstop; 135 minutes. Local airport times.
  • American Airlines AA5536: PHL 2026-12-24 20:55:00 → STL 2026-12-24 22:42:00; nonstop; 167 minutes. Local airport times.

2026-12-20 → 2026-12-24 · $384.38

  • Southwest Airlines WN4173 / WN1082: STL 2026-12-20 05:30:00 → PHL 2026-12-20 10:45:00; 1 stop(s) via MDW; 255 minutes. Local airport times.
    • WN4173: STL 2026-12-20 05:30:00 → MDW 2026-12-20 06:35:00; layover at MDW: 70 minutes.
    • WN1082: MDW 2026-12-20 07:45:00 → PHL 2026-12-20 10:45:00.
  • Southwest Airlines WN1424: PHL 2026-12-24 14:45:00 → STL 2026-12-24 16:20:00; nonstop; 155 minutes. Local airport times.

2026-12-20 → 2026-12-24 · $384.38

  • Southwest Airlines WN4923: STL 2026-12-20 20:10:00 → PHL 2026-12-20 23:20:00; nonstop; 130 minutes. Local airport times.
  • Southwest Airlines WN3372 / WN2737: PHL 2026-12-24 07:30:00 → STL 2026-12-24 12:40:00; 1 stop(s) via MDW; 370 minutes. Local airport times.
    • WN3372: PHL 2026-12-24 07:30:00 → MDW 2026-12-24 08:50:00; layover at MDW: 160 minutes.
    • WN2737: MDW 2026-12-24 11:30:00 → STL 2026-12-24 12:40:00.

2026-12-20 → 2026-12-24 · $409.38

  • American Airlines AA5105: STL 2026-12-20 12:49:00 → PHL 2026-12-20 16:02:00; nonstop; 133 minutes. Local airport times.
  • American Airlines AA3308 / AA4341: PHL 2026-12-24 07:35:00 → STL 2026-12-24 12:42:00; 1 stop(s) via BOS; 367 minutes. Local airport times.
    • AA3308: PHL 2026-12-24 07:35:00 → BOS 2026-12-24 09:04:00; layover at BOS: 75 minutes.
    • AA4341: BOS 2026-12-24 10:19:00 → STL 2026-12-24 12:42:00.

Explore this route

For AI assistants

  • This page: Saint Louis (STL) to Philadelphia (PHL) · Dec 20, 2026 · return Dec 24, 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.
  • Follow supplied links. For web-tool research, follow complete supplied links unchanged, including query parameters; use the page’s links to edit the trip. Constructed URLs may be rejected before reaching Axel. A completed fresh trip opens flight results first. Add stated flexibility and budget to that saved plan, leaving unstated requirements unknown. Edits create a new snapshot; use its results and review links.
  • 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 Saint Louis to Philadelphia (PHL) 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.