$70+ Cheap flights from Pennsylvania to St. Louis (STL)
This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 10/7. Fares are subject to change and may not be available on all flights or dates of travel.
PHL — STL
Sep 9 — Sep 161
Round-trip
1 adult, Economy
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Find cheap flights from Pennsylvania to St. Louis with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.3. Compare prices and book
Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from Pennsylvania to St. Louis
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Cheapest flights from Pennsylvania to St. LouisExplore the most affordable flight options available from Pennsylvania to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 10, 2026.
Explore the most affordable flight options available from Pennsylvania to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 10, 2026.
This Kiwi.com deal was found by Cheapflights users on 8/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/145:38 pm -
1 stop17h 02m
Mon 10/1910:35 am -
1 stop20h 01m
Deal found 8/7![Frontier logo]()
$135
This Kiwi.com deal was found by Cheapflights users on 8/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/52:45 pm -
1 stop27h 37m
Mon 9/76:17 pm -
1 stop11h 58m
Deal found 8/7![Frontier logo]()
$140
This Kiwi.com deal was found by Cheapflights users on 8/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/1012:43 pm -
1 stop21h 57m
Mon 10/1210:35 am -
1 stop20h 01m
Deal found 8/6![Frontier logo]()
$142
This Kiwi.com deal was found by Cheapflights users on 8/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/145:38 pm -
1 stop17h 02m
Sun 11/110:35 am -
1 stop20h 01m
Deal found 8/8![Frontier logo]()
$144
This Kiwi.com deal was found by Cheapflights users on 8/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/76:30 am -
1 stop11h 52m
Mon 9/142:29 pm -
1 stop15h 47m
Deal found 8/8![Frontier logo]()
$145
This Kiwi.com deal was found by Cheapflights users on 8/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/145:38 pm -
1 stop17h 02m
Fri 10/1610:35 am -
1 stop6h 40m
Deal found 8/9![Frontier logo]()
$146
This Kiwi.com deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/294:45 pm -
1 stop25h 37m
Mon 9/76:17 pm -
1 stop11h 58m
Deal found 8/5![Frontier logo]()
$148
This Kiwi.com deal was found by Cheapflights users on 8/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/1012:40 pm -
1 stop25h 30m
Mon 9/142:29 pm -
1 stop15h 47m
Deal found 8/6![Frontier logo]()
$149
This Kiwi.com deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/24:45 pm -
1 stop25h 37m
Sun 9/66:17 pm -
1 stop17h 09m
Deal found 8/5![Frontier logo]()
$150
This Kiwi.com deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/38:30 am -
1 stop9h 52m
Mon 9/76:17 pm -
1 stop11h 58m
Deal found 8/5![Frontier logo]()
$151
This Kiwi.com deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/24:45 pm -
1 stop25h 37m
Mon 9/76:17 pm -
1 stop17h 09m
Deal found 8/5![Frontier logo]()
$153
This Kiwi.com deal was found by Cheapflights users on 8/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/15:32 pm -
1 stop20h 38m
Thu 10/810:35 am -
1 stop20h 01m
Deal found 8/7![Frontier logo]()
$154
Best flights from Pennsylvania to St. LouisDiscover carefully curated flight deals from Pennsylvania to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 10, 2026.
Discover carefully curated flight deals from Pennsylvania to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 10, 2026.
This Southwest deal was found by Cheapflights users on 8/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/16:40 am -
Nonstop1h 40m
Fri 9/47:35 pm -
Nonstop1h 45m
Deal found 8/9![Southwest logo]()
$188
This Delta deal was found by Cheapflights users on 8/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/136:00 am -
1 stop5h 51m
Fri 10/167:20 pm -
1 stop4h 26m
Deal found 8/7![Delta logo]()
$247
This United Airlines deal was found by Cheapflights users on 8/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/305:36 pm -
1 stop6h 48m
Mon 11/28:30 am -
1 stop7h 30m
Deal found 8/8![United Airlines logo]()
$308
This American Airlines deal was found by Cheapflights users on 8/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/66:33 pm -
1 stop6h 26m
Wed 11/1111:32 am -
1 stop5h 31m
Deal found 8/7![American Airlines logo]()
$348
This Southwest deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/66:50 am -
Nonstop1h 55m
Tue 10/66:30 pm -
Nonstop1h 35m
Deal found 8/10![Southwest logo]()
$188
This Kiwi.com deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/97:30 am -
1 stop12h 45m
Tue 10/1310:35 am -
2 stops28h 09m
Deal found 8/10![Multiple Airlines logo]()
$390
This Southwest deal was found by Cheapflights users on 8/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/76:50 am -
Nonstop1h 55m
Wed 10/711:25 am -
1 stop4h 20m
Deal found 8/10![Southwest logo]()
$192
This Southwest deal was found by Cheapflights users on 8/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/297:35 am -
2 stops8h 35m
Fri 10/27:55 pm -
Nonstop1h 35m
Deal found 8/9![Southwest logo]()
$203
This Delta deal was found by Cheapflights users on 8/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/56:10 am -
1 stop4h 27m
Sat 9/53:44 pm -
1 stop5h 01m
Deal found 8/9![Delta logo]()
$257
This Southwest deal was found by Cheapflights users on 8/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/16:50 am -
Nonstop1h 55m
Mon 10/57:55 pm -
Nonstop1h 35m
Deal found 8/7![Southwest logo]()
$207
This United Airlines deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/55:45 pm -
Nonstop2h 26m
Sun 9/68:40 am -
Nonstop2h 14m
Deal found 8/5![United Airlines logo]()
$317
This Southwest deal was found by Cheapflights users on 8/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/15:50 am -
2 stops6h 45m
Sat 10/310:30 am -
Nonstop1h 35m
Deal found 8/8![Southwest logo]()
$222
This Delta deal was found by Cheapflights users on 8/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/148:08 am -
1 stop6h 15m
Thu 9/1710:29 am -
1 stop5h 01m
Deal found 8/6![Delta logo]()
$299
This United Airlines deal was found by Cheapflights users on 8/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/295:35 pm -
1 stop6h 24m
Wed 9/28:40 am -
1 stop4h 36m
Deal found 8/7![United Airlines logo]()
$319
This Delta deal was found by Cheapflights users on 8/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/118:08 am -
1 stop5h 24m
Sat 9/124:10 pm -
1 stop6h 04m
Deal found 8/8![Delta logo]()
$301
This Southwest deal was found by Cheapflights users on 8/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/97:20 pm -
1 stop3h 55m
Thu 9/1010:10 am -
2 stops5h 55m
Deal found 8/7![Southwest logo]()
$232
This American Airlines deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/175:10 pm -
1 stop8h 17m
Wed 9/231:49 pm -
1 stop7h 29m
Deal found 8/5![American Airlines logo]()
$374
This United Airlines deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/26:00 am -
1 stop7h 02m
Wed 9/912:59 pm -
1 stop7h 25m
Deal found 8/5![United Airlines logo]()
$319
This Delta deal was found by Cheapflights users on 8/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/312:15 pm -
1 stop3h 59m
Sun 10/46:40 am -
1 stop3h 55m
Deal found 8/6![Delta logo]()
$310
This Southwest deal was found by Cheapflights users on 8/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/117:00 am -
Nonstop1h 45m
Sun 9/137:00 pm -
Nonstop1h 40m
Deal found 8/8![Southwest logo]()
$237
This United Airlines deal was found by Cheapflights users on 8/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/2910:32 am -
1 stop5h 59m
Wed 9/212:59 pm -
1 stop7h 01m
Deal found 8/7![United Airlines logo]()
$319
This American Airlines deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/76:40 pm -
1 stop6h 29m
Thu 10/811:31 am -
1 stop5h 39m
Deal found 8/5![American Airlines logo]()
$394
This Kiwi.com deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/172:28 pm -
1 stop27h 06m
Wed 9/232:29 pm -
2 stops28h 56m
Deal found 8/5![Multiple Airlines logo]()
$458
This United Airlines deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/45:32 pm -
1 stop5h 24m
Sat 11/78:30 am -
1 stop7h 27m
Deal found 8/5![United Airlines logo]()
$319
This Southwest deal was found by Cheapflights users on 8/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/237:20 pm -
Nonstop1h 40m
Fri 9/252:45 pm -
2 stops6h 10m
Deal found 8/9![Southwest logo]()
$242
This American Airlines deal was found by Cheapflights users on 8/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/26:15 pm -
1 stop7h 12m
Sun 10/45:10 pm -
1 stop5h 49m
Deal found 8/7![American Airlines logo]()
$397
This Delta deal was found by Cheapflights users on 8/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/86:39 am -
1 stop5h 12m
Mon 10/1210:14 am -
1 stop6h 02m
Deal found 8/6![Delta logo]()
$329
This Delta deal was found by Cheapflights users on 8/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/109:59 am -
Nonstop2h 44m
Mon 9/145:30 pm -
Nonstop2h 30m
Deal found 8/6![Delta logo]()
$331
This United Airlines deal was found by Cheapflights users on 8/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/286:30 am -
1 stop4h 42m
Tue 9/18:30 am -
1 stop7h 22m
Deal found 8/8![United Airlines logo]()
$334
This Southwest deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/512:45 pm -
2 stops7h 50m
Sun 9/63:30 pm -
Nonstop2h 05m
Deal found 8/5![Southwest logo]()
$252
Last-minute flights from Pennsylvania to St. LouisDiscover last-minute flight deals from Pennsylvania to St. Louis. Data last updated August 10, 2026 and is based on user searches.
Discover last-minute flight deals from Pennsylvania to St. Louis. Data last updated August 10, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/294:45 pm -
1 stop25h 37m
Mon 9/76:17 pm -
1 stop11h 58m
Deal found 8/5![Frontier logo]()
$148
This Southwest deal was found by Cheapflights users on 8/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/16:40 am -
Nonstop1h 40m
Fri 9/47:35 pm -
Nonstop1h 45m
Deal found 8/9![Southwest logo]()
$188
This Southwest deal was found by Cheapflights users on 8/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/16:40 am -
Nonstop1h 40m
Tue 9/810:25 am -
Nonstop1h 40m
Deal found 8/8![Southwest logo]()
$207
This Kiwi.com deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/24:45 pm -
1 stop25h 37m
Sun 9/66:17 pm -
1 stop17h 09m
Deal found 8/5![Frontier logo]()
$150
This Kiwi.com deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/24:45 pm -
1 stop25h 37m
Mon 9/76:17 pm -
1 stop17h 09m
Deal found 8/5![Frontier logo]()
$153
This Kiwi.com deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/38:30 am -
1 stop9h 52m
Mon 9/76:17 pm -
1 stop11h 58m
Deal found 8/5![Frontier logo]()
$151
This Kiwi.com deal was found by Cheapflights users on 8/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/46:30 am -
1 stop11h 52m
Mon 9/76:17 pm -
1 stop11h 58m
Deal found 8/6![Frontier logo]()
$155
This Kiwi.com deal was found by Cheapflights users on 8/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/52:45 pm -
1 stop27h 37m
Mon 9/76:17 pm -
1 stop11h 58m
Deal found 8/7![Frontier logo]()
$140
This Kiwi.com deal was found by Cheapflights users on 8/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/54:45 pm -
1 stop25h 37m
Wed 9/92:29 pm -
1 stop7h 49m
Deal found 8/9![Frontier logo]()
$156
This Kiwi.com deal was found by Cheapflights users on 8/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/76:30 am -
1 stop11h 52m
Mon 9/142:29 pm -
1 stop15h 47m
Deal found 8/8![Frontier logo]()
$145
This Kiwi.com deal was found by Cheapflights users on 8/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/98:41 am -
1 stop5h 29m
Mon 9/142:29 pm -
2 stops19h 33m
Deal found 8/7![Frontier logo]()
$157
This Kiwi.com deal was found by Cheapflights users on 8/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/1012:40 pm -
1 stop25h 30m
Mon 9/142:29 pm -
1 stop15h 47m
Deal found 8/6![Frontier logo]()
$149
One-way flights from Pennsylvania to St. LouisSearch for one-way flight options from Pennsylvania to St. Louis. Find affordable one-way fares based on user searches. Data last updated August 10, 2026.
Search for one-way flight options from Pennsylvania to St. Louis. Find affordable one-way fares based on user searches. Data last updated August 10, 2026.
This Kiwi.com deal was found by Cheapflights users on 8/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/712:40 pm -
1 stop22h 00m
Deal found 8/6![Frontier logo]()
$70
This Kiwi.com deal was found by Cheapflights users on 8/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/412:43 pm -
1 stop21h 57m
Deal found 8/7![Frontier logo]()
$71
This Kiwi.com deal was found by Cheapflights users on 8/8. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/54:45 pm -
1 stop25h 37m
Deal found 8/8![Frontier logo]()
$74
This Kiwi.com deal was found by Cheapflights users on 8/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/58:41 am -
1 stop5h 29m
Deal found 8/6![Frontier logo]()
$75
This Kiwi.com deal was found by Cheapflights users on 8/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/105:38 pm -
1 stop17h 02m
Deal found 8/9![Frontier logo]()
$77
This Kiwi.com deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/36:30 am -
1 stop11h 52m
Deal found 8/5![Frontier logo]()
$78
This Kiwi.com deal was found by Cheapflights users on 8/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/812:43 pm -
1 stop21h 57m
Deal found 8/9![Frontier logo]()
$79
This Kiwi.com deal was found by Cheapflights users on 8/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/167:59 pm -
2 stops42h 11m
Deal found 8/7![Frontier logo]()
$80
This Kiwi.com deal was found by Cheapflights users on 8/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/45:32 pm -
1 stop20h 38m
Deal found 8/6![Frontier logo]()
$81
This Kiwi.com deal was found by Cheapflights users on 8/6. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/1512:40 pm -
1 stop25h 30m
Deal found 8/6![Frontier logo]()
$83
This Kiwi.com deal was found by Cheapflights users on 8/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/105:32 pm -
1 stop20h 38m
Deal found 8/5![Frontier logo]()
$84
This Southwest deal was found by Cheapflights users on 8/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/17:20 pm -
Nonstop1h 40m
Deal found 8/9![Southwest logo]()
$86
Find flight deals from Pennsylvania to St. Louis
Keep the following information in mind while searching for Pennsylvania to St. Louis flight deals. Data was last updated August 10, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $135 (Kiwi.com) |
One-way from | $70 (Kiwi.com) |
Popular in | June |
Cheapest in | September |
Average price | $387 |
Good round-trip deal | $352 or less |
Good one-way deal | $160 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Pennsylvania to St. Louis that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated August 10, 2026.
Use the filters below to find and compare flights from Pennsylvania to St. Louis that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
Quickest round-trip
PittsburghSt. Louis
PIT Pittsburgh - STL Lambert-St Louis
PITSTL
Pittsburgh
Tue 9/1
6:40 am-7:20 am
Nonstop1h 40m
Lambert-St Louis
Fri 9/4
7:35 pm-10:20 pm
Nonstop1h 45m
$188
PittsburghSt. Louis
PIT Pittsburgh - STL Lambert-St Louis
PITSTL
Pittsburgh
Tue 10/6
6:50 am-7:45 am
Nonstop1h 55m
Lambert-St Louis
Tue 10/6
6:30 pm-9:05 pm
Nonstop1h 35m
$188
PittsburghSt. Louis
PIT Pittsburgh - STL Lambert-St Louis
PITSTL
Pittsburgh
Wed 10/7
6:50 am-7:45 am
Nonstop1h 55m
Lambert-St Louis
Wed 10/7
11:25 am-4:45 pm
1 stop4h 20m
$192
PittsburghSt. Louis
PIT Pittsburgh - STL Lambert-St Louis
PITSTL
Pittsburgh
Tue 9/29
7:35 am-3:10 pm
2 stops8h 35m
Lambert-St Louis
Fri 10/2
7:55 pm-10:30 pm
Nonstop1h 35m
$203
PittsburghSt. Louis
PIT Pittsburgh - STL Lambert-St Louis
PITSTL
Pittsburgh
Thu 10/1
6:50 am-7:45 am
Nonstop1h 55m
Lambert-St Louis
Mon 10/5
7:55 pm-10:30 pm
Nonstop1h 35m
$207
PittsburghSt. Louis
PIT Pittsburgh - STL Lambert-St Louis
PITSTL
Pittsburgh
Thu 10/1
5:50 am-11:35 am
2 stops6h 45m
Lambert-St Louis
Sat 10/3
10:30 am-1:05 pm
Nonstop1h 35m
$222
PittsburghSt. Louis
PIT Pittsburgh - STL Lambert-St Louis
PITSTL
Pittsburgh
Wed 9/9
7:20 pm-10:15 pm
1 stop3h 55m
Lambert-St Louis
Thu 9/10
10:10 am-5:05 pm
2 stops5h 55m
$232
PittsburghSt. Louis
PIT Pittsburgh - STL Lambert-St Louis
PITSTL
Pittsburgh
Fri 9/11
7:00 am-7:45 am
Nonstop1h 45m
Lambert-St Louis
Sun 9/13
7:00 pm-9:40 pm
Nonstop1h 40m
$237
PittsburghSt. Louis
PIT Pittsburgh - STL Lambert-St Louis
PITSTL
Pittsburgh
Wed 9/23
7:20 pm-8:00 pm
Nonstop1h 40m
Lambert-St Louis
Fri 9/25
2:45 pm-9:55 pm
2 stops6h 10m
$242
PittsburghSt. Louis
PIT Pittsburgh - STL Lambert-St Louis
PITSTL
Pittsburgh
Tue 10/13
6:00 am-10:51 am
1 stop5h 51m
Lambert-St Louis
Fri 10/16
7:20 pm-12:46 am
1 stop4h 26m
$247
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from Pennsylvania to St. Louis
Have a flexible travel schedule? Discover the best time to fly to St. Louis from Pennsylvania with our price prediction graph.
PIT-STL
DCA-STL
ABE-STL
IAD-STL
PHL-STL
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.
Cheapflights Insights
Everything you need to know about your flight from Pennsylvania to St. Louis
USPA-STL
PIT-STL
DCA-STL
ABE-STL
IAD-STL
What is the cheapest month to book a flight from Pennsylvania to St. Louis?
Currently, September is the cheapest month in which you can book a flight from Pennsylvania to St. Louis (average of $333). Flying from Pennsylvania to St. Louis in June is currently the most expensive (average of $470). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.
What is the cheapest time of day to fly from PA to STL?
Find hourly flight availability from Pennsylvania to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated August 10, 2026.
When flying from Pennsylvania to St. Louis, the time of day you fly usually plays a role in the price. Save by searching for a flight in the afternoon, which can drop the price by up to 14% versus a flight in the morning.
Weekly flight availability from Pennsylvania to St. Louis
Explore weekly flight availability from Pennsylvania to St. Louis. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated August 10, 2026.
The most flights from USPA to STL are scheduled on a Monday (9 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (7 on average).
How much does it cost to fly round-trip from Pennsylvania to St. Louis?
Airfare is below average for this route at the moment.
Pennsylvania to St. Louis flights typically cost between $277 and $463 in October.The cheapest round-trip price found within the last 5 days was $135 on Frontier (Oct 14-Oct 19).
How far ahead should I book a flight from Pennsylvania to St. Louis?
To ensure you get the cheapest price possible for a flight from Pennsylvania to St. Louis, you should look to book at least 37 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.
What is the cheapest day to fly from Pennsylvania to St. Louis?
Use this chart to determine the cheapest time to fly round-trip from Pennsylvania to St. Louis. Price data was last updated on August 8, 2026.
Travelers seeking maximum savings on their Pennsylvania to St. Louis flight should consider departing on Thursday at noon when fares are most often at their lowest. Sunday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.
Related info for your journey
Find useful and relevant information for your journey from Pennsylvania to St. Louis. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near St. Louis?
Book flights to St. Louis if you plan to visit one of these locationsEdwardsville
Fairview Heights
O'Fallon
Fenton
Swansea
Eureka
Maryland Heights
Collinsville
Wentzville
Glencoe
Chesterfield
Farmington
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Alternative routes for Pennsylvania to St. Louis
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Complete your trip
Complete your trip to St. Louis by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Pennsylvania to St. Louis by cabin class
Find flights from Pennsylvania to St. Louis, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Pennsylvania and St. Louis flights
Browse other Pennsylvania and St. Louis flight options. Last updated on August 10, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Other flights to St. Louis
Explore flights to St. Louis departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on August 10, 2026.
Pennsylvania to St. Louis flights
Consider these flights traveling from Pennsylvania to St. Louis.
Top 5 airlines flying from Pennsylvania to St. Louis
Discover the top 5 airlines that operate flights from Pennsylvania to St. Louis. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated August 10, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$144 | Average$226 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$158 | Average$414 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$188 | Average$387 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$230 | Average$405 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$248 | Average$405 | FlexibilityNo cancel fee | On-time69% |