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

Philadelphia → Saint Louis

Dec 12, 2026 · choose your return date

PHL → STL1 adulteconomyOne way and round trips

30 flight options · 3 airlines

Choose your return date

One-way flights and round trips by duration. Flights for 1 adult in economy. Prices are total for all travelers in USD, including required taxes. Basic economy may apply.

December 2026

Dec 12, 2026 · One wayFrontier AirlinesUp to 1 stop each way$95.00 Dec 12, 2026 · One waySouthwest AirlinesNonstop$155.00 Dec 12, 2026 – Dec 13, 2026 · 1 nightFrontier AirlinesUp to 1 stop each way$180.00 Dec 12, 2026 – Dec 13, 2026 · 1 nightSouthwest AirlinesNonstop$300.00 Dec 12, 2026 – Dec 14, 2026 · 2 nightsFrontier AirlinesUp to 1 stop each way$180.00 Dec 12, 2026 – Dec 14, 2026 · 2 nightsSouthwest AirlinesNonstop$300.00 Dec 12, 2026 – Dec 15, 2026 · 3 nightsFrontier AirlinesUp to 1 stop each way$180.00 Dec 12, 2026 – Dec 15, 2026 · 3 nightsSouthwest AirlinesNonstop$300.00 Dec 12, 2026 – Dec 16, 2026 · 4 nightsFrontier AirlinesUp to 1 stop each way$180.00 Dec 12, 2026 – Dec 16, 2026 · 4 nightsAmerican AirlinesNonstop$340.00 Dec 12, 2026 – Dec 17, 2026 · 5 nightsFrontier AirlinesUp to 1 stop each way$180.00 Dec 12, 2026 – Dec 17, 2026 · 5 nightsSouthwest AirlinesNonstop$300.00 Dec 12, 2026 – Dec 18, 2026 · 6 nightsFrontier AirlinesUp to 1 stop each way$207.00 Dec 12, 2026 – Dec 18, 2026 · 6 nightsSouthwest AirlinesNonstop$345.00 Dec 12, 2026 – Dec 19, 2026 · 7 nightsFrontier AirlinesUp to 1 stop each way$207.00 Dec 12, 2026 – Dec 19, 2026 · 7 nightsSouthwest AirlinesNonstop$345.00 Dec 12, 2026 – Dec 20, 2026 · 8 nightsFrontier AirlinesUp to 1 stop each way$207.00 Dec 12, 2026 – Dec 20, 2026 · 8 nightsSouthwest AirlinesNonstop$345.00 Dec 12, 2026 – Dec 21, 2026 · 9 nightsFrontier AirlinesUp to 1 stop each way$207.00 Dec 12, 2026 – Dec 21, 2026 · 9 nightsSouthwest AirlinesNonstop$345.00 Dec 12, 2026 – Dec 22, 2026 · 10 nightsFrontier AirlinesUp to 1 stop each way$207.00 Dec 12, 2026 – Dec 22, 2026 · 10 nightsSouthwest AirlinesNonstop$345.00 Dec 12, 2026 – Dec 23, 2026 · 11 nightsFrontier AirlinesUp to 1 stop each way$207.00 Dec 12, 2026 – Dec 23, 2026 · 11 nightsAmerican AirlinesNonstop$391.00 Dec 12, 2026 – Dec 24, 2026 · 12 nightsFrontier AirlinesUp to 1 stop each way$207.00 Dec 12, 2026 – Dec 24, 2026 · 12 nightsSouthwest AirlinesNonstop$345.00 Dec 12, 2026 – Dec 25, 2026 · 13 nightsFrontier AirlinesUp to 1 stop each way$207.00 Dec 12, 2026 – Dec 25, 2026 · 13 nightsSouthwest AirlinesNonstop$345.00 Dec 12, 2026 – Dec 26, 2026 · 14 nightsFrontier AirlinesUp to 1 stop each way$207.00 Dec 12, 2026 – Dec 26, 2026 · 14 nightsSouthwest AirlinesNonstop$345.00

Flights for your trip

  1. Sat, Dec 12 · One way

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

    One-way total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  2. Sat, Dec 12 · One way

    Southwest Airlines
    6:00 amPHL
    2h 40m
    Nonstop
    7:40 amSTL

    One-way total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  3. Sat, Dec 12 – Sun, Dec 13

    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

    Availability is checked when you select these flights.

  4. Sat, Dec 12 – Sun, Dec 13

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

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  5. Sat, Dec 12 – Mon, Dec 14

    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

    Availability is checked when you select these flights.

  6. Sat, Dec 12 – Mon, Dec 14

    Southwest Airlines
    6:00 amPHL
    2h 40m
    Nonstop
    7:40 amSTL
    Southwest Airlines
    6:20 pmSTL
    2h 10m
    Nonstop
    9:30 pmPHL

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  7. Sat, Dec 12 – Tue, Dec 15

    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

    Availability is checked when you select these flights.

  8. Sat, Dec 12 – Tue, Dec 15

    Southwest Airlines
    6:00 amPHL
    2h 40m
    Nonstop
    7:40 amSTL
    Southwest Airlines
    6:20 pmSTL
    2h 10m
    Nonstop
    9:30 pmPHL

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  9. Sat, Dec 12 – Wed, Dec 16

    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

    Availability is checked when you select these flights.

  10. Sat, Dec 12 – Wed, Dec 16

    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

    Availability is checked when you select these flights.

  11. Sat, Dec 12 – Fri, Dec 18

    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

    Availability is checked when you select these flights.

  12. Sat, Dec 12 – Fri, Dec 18

    Southwest Airlines
    6:00 amPHL
    2h 40m
    Nonstop
    7:40 amSTL
    Southwest Airlines
    6:20 pmSTL
    2h 10m
    Nonstop
    9:30 pmPHL

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  13. Sat, Dec 12 – Sat, Dec 19

    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

    Availability is checked when you select these flights.

  14. Sat, Dec 12 – Sat, Dec 19

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

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  15. Sat, Dec 12 – Sun, Dec 20

    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

    Availability is checked when you select these flights.

  16. Sat, Dec 12 – Sun, Dec 20

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

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  17. Sat, Dec 12 – Tue, Dec 22

    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

    Availability is checked when you select these flights.

  18. Sat, Dec 12 – Tue, Dec 22

    Southwest Airlines
    6:00 amPHL
    2h 40m
    Nonstop
    7:40 amSTL
    Southwest Airlines
    6:20 pmSTL
    2h 10m
    Nonstop
    9:30 pmPHL

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  19. Sat, Dec 12 – Wed, Dec 23

    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

    Availability is checked when you select these flights.

  20. Sat, Dec 12 – Wed, Dec 23

    American Airlines
    8:55 pmPHL
    2h 47m
    Nonstop
    10:42 pmSTL
    American Airlines
    6:12 amSTL
    2h 20m
    Nonstop
    9:32 amPHL

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  21. Sat, Dec 12 – Thu, Dec 24

    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

    Availability is checked when you select these flights.

  22. Sat, Dec 12 – Thu, Dec 24

    Southwest Airlines
    6:00 amPHL
    2h 40m
    Nonstop
    7:40 amSTL
    Southwest Airlines
    6:20 pmSTL
    2h 10m
    Nonstop
    9:30 pmPHL

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

  23. Sat, Dec 12 – Sat, Dec 26

    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

    Availability is checked when you select these flights.

  24. Sat, Dec 12 – Sat, Dec 26

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

    Round-trip total · 1 adult · Taxes included

    Availability is checked when you select these flights.

Swipe to see 23 more recent deals.

1 of 24

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 11, 2026 · Return optionsDec 13, 2026 · Return optionsHotels in St. Louis with Axel
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Flights for 1 adult in economy. Prices are total for all travelers in USD, including required taxes. Basic economy may apply.

Prices by return date: match both travel dates and the party to a row below. Each total is for that exact trip, issued at the time shown. To book or select flights, follow that row's price link; it keeps the exact dates and travelers.

Exact travel datesAirlineFlightsTotal pricePrice issued (UTC)
2026-12-12 · one waySouthwest AirlinesWN3375Axel-exclusive $155.002026-10-29T01:56:03Z
2026-12-12 · one wayFrontier AirlinesF91147 + F94473Axel-exclusive $95.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-13Southwest AirlinesWN3375 / WN4922Axel-exclusive $300.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-13Frontier AirlinesF91147 + F94473 / F94474 + F92298Axel-exclusive $180.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-14Southwest AirlinesWN3375 / WN4923Axel-exclusive $300.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-14Frontier AirlinesF91147 + F94473 / F94474 + F92298Axel-exclusive $180.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-15Southwest AirlinesWN3375 / WN4923Axel-exclusive $300.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-15Frontier AirlinesF91147 + F94473 / F94474 + F92298Axel-exclusive $180.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-16American AirlinesAA5536 / AA5477Axel-exclusive $340.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-16Frontier AirlinesF91147 + F94473 / F94474 + F92298Axel-exclusive $180.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-17Southwest AirlinesWN3375 / WN4923Axel-exclusive $300.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-17Frontier AirlinesF91147 + F94473 / F94474 + F92298Axel-exclusive $180.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-18Southwest AirlinesWN3375 / WN4923Axel-exclusive $345.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-18Frontier AirlinesF91147 + F94473 / F94474 + F92298Axel-exclusive $207.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-19Southwest AirlinesWN3375 / WN3331Axel-exclusive $345.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-19Frontier AirlinesF91147 + F94473 / F94474 + F92298Axel-exclusive $207.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-20Southwest AirlinesWN3375 / WN4922Axel-exclusive $345.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-20Frontier AirlinesF91147 + F94473 / F94474 + F92298Axel-exclusive $207.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-21Southwest AirlinesWN3375 / WN4923Axel-exclusive $345.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-21Frontier AirlinesF91147 + F94473 / F94474 + F92298Axel-exclusive $207.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-22Southwest AirlinesWN3375 / WN4923Axel-exclusive $345.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-22Frontier AirlinesF91147 + F94473 / F94474 + F92298Axel-exclusive $207.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-23American AirlinesAA5536 / AA5308Axel-exclusive $391.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-23Frontier AirlinesF91147 + F94473 / F94474 + F92298Axel-exclusive $207.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-24Southwest AirlinesWN3375 / WN4923Axel-exclusive $345.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-24Frontier AirlinesF91147 + F94473 / F94474 + F92298Axel-exclusive $207.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-25Southwest AirlinesWN3375 / WN4923Axel-exclusive $345.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-25Frontier AirlinesF91147 + F94473 / F94474 + F92298Axel-exclusive $207.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-26Southwest AirlinesWN3375 / WN3331Axel-exclusive $345.002026-10-29T01:56:03Z
2026-12-12 → 2026-12-26Frontier AirlinesF91147 + F94473 / F94474 + F92298Axel-exclusive $207.002026-10-29T01:56:03Z

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

2026-12-12 · one way · Axel-exclusive $95.00

  • Frontier Airlines F91147 / F94473: PHL 2026-12-12 12:49:00 → STL 2026-12-12 17:42:00; 1 stop(s) via ATL; 353 minutes. Local airport times.
    • F91147: PHL 2026-12-12 12:49:00 → ATL 2026-12-12 15:19:00; layover at ATL: 90 minutes.
    • F94473: ATL 2026-12-12 16:49:00 → STL 2026-12-12 17:42:00.

2026-12-12 · one way · Axel-exclusive $155.00

  • Southwest Airlines WN3375: PHL 2026-12-12 06:00:00 → STL 2026-12-12 07:40:00; nonstop; 160 minutes. Local airport times.

2026-12-12 → 2026-12-13 · Axel-exclusive $180.00

  • Frontier Airlines F91147 / F94473: PHL 2026-12-12 12:49:00 → STL 2026-12-12 17:42:00; 1 stop(s) via ATL; 353 minutes. Local airport times.
    • F91147: PHL 2026-12-12 12:49:00 → ATL 2026-12-12 15:19:00; layover at ATL: 90 minutes.
    • F94473: ATL 2026-12-12 16:49:00 → STL 2026-12-12 17:42:00.
  • Frontier Airlines F94474 / F92298: STL 2026-12-13 12:02:00 → PHL 2026-12-13 18:32:00; 1 stop(s) via ATL; 330 minutes. Local airport times.
    • F94474: STL 2026-12-13 12:02:00 → ATL 2026-12-13 14:42:00; layover at ATL: 102 minutes.
    • F92298: ATL 2026-12-13 16:24:00 → PHL 2026-12-13 18:32:00.

2026-12-12 → 2026-12-13 · Axel-exclusive $300.00

  • Southwest Airlines WN3375: PHL 2026-12-12 06:00:00 → STL 2026-12-12 07:40:00; nonstop; 160 minutes. Local airport times.
  • Southwest Airlines WN4922: STL 2026-12-13 10:40:00 → PHL 2026-12-13 13:50:00; nonstop; 130 minutes. Local airport times.

2026-12-12 → 2026-12-14 · Axel-exclusive $180.00

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

2026-12-12 → 2026-12-14 · Axel-exclusive $300.00

  • Southwest Airlines WN3375: PHL 2026-12-12 06:00:00 → STL 2026-12-12 07:40:00; nonstop; 160 minutes. Local airport times.
  • Southwest Airlines WN4923: STL 2026-12-14 18:20:00 → PHL 2026-12-14 21:30:00; nonstop; 130 minutes. Local airport times.

2026-12-12 → 2026-12-15 · Axel-exclusive $180.00

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

2026-12-12 → 2026-12-15 · Axel-exclusive $300.00

  • Southwest Airlines WN3375: PHL 2026-12-12 06:00:00 → STL 2026-12-12 07:40:00; nonstop; 160 minutes. Local airport times.
  • Southwest Airlines WN4923: STL 2026-12-15 18:20:00 → PHL 2026-12-15 21:30:00; nonstop; 130 minutes. Local airport times.

2026-12-12 → 2026-12-16 · Axel-exclusive $180.00

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

2026-12-12 → 2026-12-16 · Axel-exclusive $340.00

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

2026-12-12 → 2026-12-18 · Axel-exclusive $207.00

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

2026-12-12 → 2026-12-18 · Axel-exclusive $345.00

  • Southwest Airlines WN3375: PHL 2026-12-12 06:00:00 → STL 2026-12-12 07:40:00; nonstop; 160 minutes. Local airport times.
  • Southwest Airlines WN4923: STL 2026-12-18 18:20:00 → PHL 2026-12-18 21:30:00; nonstop; 130 minutes. Local airport times.

2026-12-12 → 2026-12-19 · Axel-exclusive $207.00

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

2026-12-12 → 2026-12-19 · Axel-exclusive $345.00

  • Southwest Airlines WN3375: PHL 2026-12-12 06:00:00 → STL 2026-12-12 07:40:00; nonstop; 160 minutes. Local airport times.
  • Southwest Airlines WN3331: STL 2026-12-19 10:00:00 → PHL 2026-12-19 13:10:00; nonstop; 130 minutes. Local airport times.

2026-12-12 → 2026-12-20 · Axel-exclusive $207.00

  • Frontier Airlines F91147 / F94473: PHL 2026-12-12 12:49:00 → STL 2026-12-12 17:42:00; 1 stop(s) via ATL; 353 minutes. Local airport times.
    • F91147: PHL 2026-12-12 12:49:00 → ATL 2026-12-12 15:19:00; layover at ATL: 90 minutes.
    • F94473: ATL 2026-12-12 16:49:00 → STL 2026-12-12 17:42:00.
  • 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.

2026-12-12 → 2026-12-20 · Axel-exclusive $345.00

  • Southwest Airlines WN3375: PHL 2026-12-12 06:00:00 → STL 2026-12-12 07:40:00; nonstop; 160 minutes. Local airport times.
  • Southwest Airlines WN4922: STL 2026-12-20 10:40:00 → PHL 2026-12-20 13:50:00; nonstop; 130 minutes. Local airport times.

2026-12-12 → 2026-12-22 · Axel-exclusive $207.00

  • Frontier Airlines F91147 / F94473: PHL 2026-12-12 12:49:00 → STL 2026-12-12 17:42:00; 1 stop(s) via ATL; 353 minutes. Local airport times.
    • F91147: PHL 2026-12-12 12:49:00 → ATL 2026-12-12 15:19:00; layover at ATL: 90 minutes.
    • F94473: ATL 2026-12-12 16:49:00 → STL 2026-12-12 17:42:00.
  • Frontier Airlines F94474 / F92298: STL 2026-12-22 12:02:00 → PHL 2026-12-22 18:32:00; 1 stop(s) via ATL; 330 minutes. Local airport times.
    • F94474: STL 2026-12-22 12:02:00 → ATL 2026-12-22 14:42:00; layover at ATL: 102 minutes.
    • F92298: ATL 2026-12-22 16:24:00 → PHL 2026-12-22 18:32:00.

2026-12-12 → 2026-12-22 · Axel-exclusive $345.00

  • Southwest Airlines WN3375: PHL 2026-12-12 06:00:00 → STL 2026-12-12 07:40:00; nonstop; 160 minutes. Local airport times.
  • Southwest Airlines WN4923: STL 2026-12-22 18:20:00 → PHL 2026-12-22 21:30:00; nonstop; 130 minutes. Local airport times.

2026-12-12 → 2026-12-23 · Axel-exclusive $207.00

  • Frontier Airlines F91147 / F94473: PHL 2026-12-12 12:49:00 → STL 2026-12-12 17:42:00; 1 stop(s) via ATL; 353 minutes. Local airport times.
    • F91147: PHL 2026-12-12 12:49:00 → ATL 2026-12-12 15:19:00; layover at ATL: 90 minutes.
    • F94473: ATL 2026-12-12 16:49:00 → STL 2026-12-12 17:42:00.
  • Frontier Airlines F94474 / F92298: STL 2026-12-23 12:02:00 → PHL 2026-12-23 18:32:00; 1 stop(s) via ATL; 330 minutes. Local airport times.
    • F94474: STL 2026-12-23 12:02:00 → ATL 2026-12-23 14:42:00; layover at ATL: 102 minutes.
    • F92298: ATL 2026-12-23 16:24:00 → PHL 2026-12-23 18:32:00.

2026-12-12 → 2026-12-23 · Axel-exclusive $391.00

  • American Airlines AA5536: PHL 2026-12-12 20:55:00 → STL 2026-12-12 22:42:00; nonstop; 167 minutes. Local airport times.
  • American Airlines AA5308: STL 2026-12-23 06:12:00 → PHL 2026-12-23 09:32:00; nonstop; 140 minutes. Local airport times.

2026-12-12 → 2026-12-24 · Axel-exclusive $207.00

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

2026-12-12 → 2026-12-24 · Axel-exclusive $345.00

  • Southwest Airlines WN3375: PHL 2026-12-12 06:00:00 → STL 2026-12-12 07:40:00; nonstop; 160 minutes. Local airport times.
  • Southwest Airlines WN4923: STL 2026-12-24 18:20:00 → PHL 2026-12-24 21:30:00; nonstop; 130 minutes. Local airport times.

2026-12-12 → 2026-12-26 · Axel-exclusive $207.00

  • Frontier Airlines F91147 / F94473: PHL 2026-12-12 12:49:00 → STL 2026-12-12 17:42:00; 1 stop(s) via ATL; 353 minutes. Local airport times.
    • F91147: PHL 2026-12-12 12:49:00 → ATL 2026-12-12 15:19:00; layover at ATL: 90 minutes.
    • F94473: ATL 2026-12-12 16:49:00 → STL 2026-12-12 17:42:00.
  • Frontier Airlines F94474 / F92298: STL 2026-12-26 12:02:00 → PHL 2026-12-26 18:32:00; 1 stop(s) via ATL; 330 minutes. Local airport times.
    • F94474: STL 2026-12-26 12:02:00 → ATL 2026-12-26 14:42:00; layover at ATL: 102 minutes.
    • F92298: ATL 2026-12-26 16:24:00 → PHL 2026-12-26 18:32:00.

2026-12-12 → 2026-12-26 · Axel-exclusive $345.00

  • Southwest Airlines WN3375: PHL 2026-12-12 06:00:00 → STL 2026-12-12 07:40:00; nonstop; 160 minutes. Local airport times.
  • Southwest Airlines WN3331: STL 2026-12-26 10:00:00 → PHL 2026-12-26 13:10:00; nonstop; 130 minutes. Local airport times.

Explore this route

For AI assistants

  • This page: Philadelphia (PHL) to Saint Louis (STL) · Dec 12, 2026 · choose your return date: 1 adult in economy, every priced fare with its flights, times and total, each with the time its price was issued.
  • Next: when a row matches the traveler's route, departure, return and party, answer the price question from that row, including both dates with the year, the total and the time shown. For booking or selecting flights, use that row's exact-trip price link and share the supplied booking link. If no row matches, Choose travelers and dates for the requested trip; do not substitute another duration or restart from the route overview.
  • 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 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. Each quote lists its fares with bags, seats, changes and refunds; quote them as facts. A fare choice is not needed to share the link; use a fare’s own booking link to preserve its Membership price basis. Ask only for essential missing trip details. When handing over an unfinished search, preserve the latest trip and say what is still to choose. 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.