$86+ Cheap flights from St. Louis (STL) to Pennsylvania
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 7/6. Fares are subject to change and may not be available on all flights or dates of travel.
STL — PHL
Jul 16 — Jul 231
Round-trip
1 adult, Economy
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Cheapest flights from St. Louis to PennsylvaniaExplore the most affordable flight options available from St. Louis to Pennsylvania. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 16, 2026.
Explore the most affordable flight options available from St. Louis to Pennsylvania. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 16, 2026.
This United Airlines deal was found by Cheapflights users on 6/14. 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.
Tue 9/18:00 am
STL
- PIT
1 stop4h 15m
United Airlines
Wed 9/3010:56 am
PIT
- STL
1 stop4h 21m
United Airlines
Deal found 6/14![United Airlines logo]()
$196
This United Airlines deal was found by Cheapflights users on 6/13. 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 9/128:50 am
STL
- PIT
1 stop5h 35m
United Airlines
Sat 9/196:10 pm
PIT
- STL
1 stop4h 20m
United Airlines
Deal found 6/13![United Airlines logo]()
$201
This Southwest deal was found by Cheapflights users on 6/14. 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 pm
STL
- PIT
Nonstop1h 35m
Southwest
Wed 9/307:20 pm
PIT
- STL
Nonstop1h 40m
Southwest
Deal found 6/14![Southwest logo]()
$219
This United Airlines deal was found by Cheapflights users on 6/14. 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 8/57:20 am
STL
- PIT
1 stop4h 48m
United Airlines
Sat 8/86:16 pm
PIT
- STL
1 stop4h 10m
United Airlines
Deal found 6/14![United Airlines logo]()
$225
This Southwest deal was found by Cheapflights users on 6/11. 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 9/125:45 am
STL
- PIT
1 stop3h 20m
Southwest
Sat 9/196:50 am
PIT
- STL
Nonstop1h 40m
Southwest
Deal found 6/11![Southwest logo]()
$238
This Delta deal was found by Cheapflights users on 6/13. 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.
Wed 9/96:00 am
STL
- PIT
1 stop6h 36m
Delta
Tue 9/226:00 am
PIT
- STL
1 stop4h 29m
Delta
Deal found 6/13![Delta logo]()
$239
This American Airlines deal was found by Cheapflights users on 6/11. 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 9/115:00 am
STL
- PIT
1 stop5h 01m
American Airlines
Sat 9/1910:16 am
PIT
- STL
1 stop4h 00m
American Airlines
Deal found 6/11![American Airlines logo]()
$242
This Delta deal was found by Cheapflights users on 6/13. 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.
Wed 9/97:05 am
STL
- PIT
1 stop5h 31m
Delta
Sat 9/1912:15 pm
PIT
- STL
1 stop3h 59m
Delta
Deal found 6/13![Delta logo]()
$247
This Delta deal was found by Cheapflights users on 6/13. 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 9/106:40 am
STL
- PIT
1 stop3h 39m
Delta
Thu 9/176:00 am
PIT
- STL
1 stop5h 55m
Delta
Deal found 6/13![Delta logo]()
$255
This Southwest deal was found by Cheapflights users on 6/11. 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 9/116:05 am
STL
- PIT
1 stop5h 05m
Southwest
Sat 9/196:50 am
PIT
- STL
Nonstop1h 40m
Southwest
Deal found 6/11![Southwest logo]()
$256
This Southwest deal was found by Cheapflights users on 6/11. 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 7/17:55 pm
STL
- DCA
Nonstop2h 00m
Southwest
Tue 7/711:45 am
DCA
- STL
1 stop4h 05m
Southwest
Deal found 6/11![Southwest logo]()
$263
This Frontier deal was found by Cheapflights users on 6/14. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/67:10 pm
STL
- IAD
1 stop12h 10m
Frontier
Sat 7/111:21 pm
IAD
- STL
1 stop11h 38m
Frontier
Deal found 6/14![Frontier logo]()
$263
Best flights from St. Louis to PennsylvaniaDiscover carefully curated flight deals from St. Louis to Pennsylvania that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 16, 2026.
Discover carefully curated flight deals from St. Louis to Pennsylvania that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 16, 2026.
This United Airlines deal was found by Cheapflights users on 6/14. 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.
Tue 9/18:00 am
STL
- PIT
1 stop4h 15m
United Airlines
Wed 9/3010:56 am
PIT
- STL
1 stop4h 21m
United Airlines
Deal found 6/14![United Airlines logo]()
$196
This Southwest deal was found by Cheapflights users on 6/12. 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 7/2810:25 am
STL
- PIT
Nonstop1h 35m
Southwest
Mon 8/38:15 pm
PIT
- STL
Nonstop1h 45m
Southwest
Deal found 6/12![Southwest logo]()
$261
This Delta deal was found by Cheapflights users on 6/11. 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 9/115:00 pm
STL
- DCA
1 stop4h 59m
Delta
Tue 9/1511:00 am
DCA
- STL
1 stop5h 36m
Delta
Deal found 6/11![Delta logo]()
$264
This American Airlines deal was found by Cheapflights users on 6/10. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/286:55 am
STL
- PIT
1 stop4h 36m
American Airlines
Mon 8/37:45 pm
PIT
- STL
1 stop4h 47m
American Airlines
Deal found 6/10![American Airlines logo]()
$285
This Kiwi.com deal was found by Cheapflights users on 6/15. 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 7/174:57 pm
STL
- PHL
1 stop14h 42m
Frontier
Sat 7/181:32 pm
PHL
- STL
2 stops11h 27m
Frontier
Deal found 6/15![Frontier logo]()
$291
This Southwest deal was found by Cheapflights users on 6/14. 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 9/16:30 am
STL
- PIT
1 stop3h 50m
Southwest
Wed 9/307:35 am
PIT
- STL
2 stops8h 30m
Southwest
Deal found 6/14![Southwest logo]()
$266
This Delta deal was found by Cheapflights users on 6/14. 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 7/37:12 pm
STL
- IAD
1 stop4h 32m
Delta
Tue 7/148:27 am
IAD
- STL
1 stop4h 50m
Delta
Deal found 6/14![Delta logo]()
$267
This Delta deal was found by Cheapflights users on 6/15. 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 9/246:00 am
STL
- DCA
1 stop5h 42m
Delta
Sat 9/2612:32 pm
DCA
- STL
1 stop3h 42m
Delta
Deal found 6/15![Delta logo]()
$271
This Southwest deal was found by Cheapflights users on 6/13. 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 7/87:55 pm
STL
- DCA
Nonstop2h 00m
Southwest
Mon 7/136:40 pm
DCA
- STL
Nonstop2h 20m
Southwest
Deal found 6/13![Southwest logo]()
$276
This United Airlines deal was found by Cheapflights users on 6/14. 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 8/14:53 pm
STL
- EWR
Nonstop2h 37m
United Airlines
Mon 8/1010:17 pm
EWR
- STL
Nonstop2h 27m
United Airlines
Deal found 6/14![United Airlines logo]()
$307
This United Airlines deal was found by Cheapflights users on 6/11. 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.
Tue 7/148:43 am
STL
- IAD
Nonstop2h 12m
United Airlines
Thu 7/166:10 am
IAD
- STL
1 stop7h 01m
United Airlines
Deal found 6/11![United Airlines logo]()
$312
This Delta deal was found by Cheapflights users on 6/12. 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 8/276:30 am
STL
- DCA
1 stop3h 58m
Delta
Mon 8/316:20 am
DCA
- STL
1 stop6h 27m
Delta
Deal found 6/12![Delta logo]()
$289
This Southwest deal was found by Cheapflights users on 6/13. 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 9/121:25 pm
STL
- PIT
2 stops6h 20m
Southwest
Sat 9/196:10 am
PIT
- STL
1 stop5h 40m
Southwest
Deal found 6/13![Southwest logo]()
$289
This Delta deal was found by Cheapflights users on 6/13. 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.
Wed 7/86:58 pm
STL
- IAD
1 stop4h 43m
Delta
Mon 7/135:46 pm
IAD
- STL
1 stop7h 07m
Delta
Deal found 6/13![Delta logo]()
$296
This United Airlines deal was found by Cheapflights users on 6/14. 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.
Tue 8/118:40 am
STL
- IAD
Nonstop2h 17m
United Airlines
Tue 8/185:45 pm
IAD
- STL
1 stop6h 53m
United Airlines
Deal found 6/14![United Airlines logo]()
$327
This Southwest deal was found by Cheapflights users on 6/10. 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 7/85:55 pm
STL
- LGA
1 stop4h 05m
Southwest
Wed 7/153:05 pm
LGA
- STL
Nonstop3h 00m
Southwest
Deal found 6/10![Southwest logo]()
$299
This Delta deal was found by Cheapflights users on 6/10. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/285:23 pm
STL
- JFK
1 stop6h 51m
Delta
Tue 9/11:10 pm
JFK
- STL
1 stop6h 17m
Delta
Deal found 6/10![Delta logo]()
$297
This Southwest deal was found by Cheapflights users on 6/12. 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 9/17:15 am
STL
- PHL
2 stops7h 45m
Southwest
Wed 9/303:00 pm
PHL
- STL
2 stops8h 10m
Southwest
Deal found 6/12![Southwest logo]()
$300
This American Airlines deal was found by Cheapflights users on 6/12. 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.
Mon 8/174:54 pm
STL
- AVP
1 stop6h 03m
American Airlines
Sat 8/226:03 am
AVP
- STL
1 stop18h 55m
American Airlines
Deal found 6/12![American Airlines logo]()
$447
This Southwest deal was found by Cheapflights users on 6/12. 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.
Mon 8/177:05 pm
STL
- PHL
Nonstop2h 10m
Southwest
Wed 8/196:25 am
PHL
- STL
Nonstop2h 15m
Southwest
Deal found 6/12![Southwest logo]()
$301
This Delta deal was found by Cheapflights users on 6/10. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/179:25 am
STL
- LGA
Nonstop2h 31m
Delta
Fri 8/216:30 am
LGA
- STL
Nonstop2h 38m
Delta
Deal found 6/10![Delta logo]()
$302
This United Airlines deal was found by Cheapflights users on 6/14. 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.
Tue 8/188:40 am
STL
- IAD
Nonstop2h 14m
United Airlines
Wed 8/198:20 am
IAD
- STL
1 stop7h 40m
United Airlines
Deal found 6/14![United Airlines logo]()
$366
This Southwest deal was found by Cheapflights users on 6/10. 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.
Sat 8/13:50 pm
STL
- LGA
1 stop6h 25m
Southwest
Tue 8/46:00 am
LGA
- STL
1 stop4h 35m
Southwest
Deal found 6/10![Southwest logo]()
$302
This Delta deal was found by Cheapflights users on 6/14. 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 8/46:05 am
STL
- LGA
Nonstop2h 33m
Delta
Tue 8/116:05 am
LGA
- STL
1 stop4h 32m
Delta
Deal found 6/14![Delta logo]()
$303
This United Airlines deal was found by Cheapflights users on 6/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/49:20 am
STL
- EWR
1 stop7h 40m
United Airlines
Sat 8/810:17 pm
EWR
- STL
Nonstop2h 27m
United Airlines
Deal found 6/10![United Airlines logo]()
$367
This Southwest deal was found by Cheapflights users on 6/11. 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 7/255:00 am
STL
- LGA
Nonstop2h 20m
Southwest
Sat 8/16:00 am
LGA
- STL
1 stop6h 25m
Southwest
Deal found 6/11![Southwest logo]()
$303
This United Airlines deal was found by Cheapflights users on 6/14. 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.
Tue 8/1812:59 pm
STL
- MDT
1 stop6h 54m
United Airlines
Sat 8/225:54 pm
MDT
- STL
1 stop5h 06m
United Airlines
Deal found 6/14![United Airlines logo]()
$371
This Delta deal was found by Cheapflights users on 6/14. 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 7/2412:28 pm
STL
- DCA
1 stop7h 31m
Delta
Wed 8/56:00 am
DCA
- STL
1 stop6h 46m
Delta
Deal found 6/14![Delta logo]()
$307
This Southwest deal was found by Cheapflights users on 6/14. 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 7/246:15 pm
STL
- PIT
1 stop5h 40m
Southwest
Mon 7/278:15 pm
PIT
- STL
Nonstop1h 45m
Southwest
Deal found 6/14![Southwest logo]()
$303
This United Airlines deal was found by Cheapflights users on 6/15. 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.
Tue 7/146:01 am
STL
- EWR
Nonstop2h 29m
United Airlines
Wed 7/1510:17 pm
EWR
- STL
Nonstop2h 27m
United Airlines
Deal found 6/15![United Airlines logo]()
$373
Last-minute flights from St. Louis to PennsylvaniaDiscover last-minute flight deals from St. Louis to Pennsylvania. Data last updated June 16, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Pennsylvania. Data last updated June 16, 2026 and is based on user searches.
This Southwest deal was found by Cheapflights users on 6/11. 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 7/17:55 pm
STL
- DCA
Nonstop2h 00m
Southwest
Tue 7/711:45 am
DCA
- STL
1 stop4h 05m
Southwest
Deal found 6/11![Southwest logo]()
$263
This Delta deal was found by Cheapflights users on 6/14. 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.
Wed 7/13:57 pm
STL
- DCA
1 stop5h 50m
Delta
Tue 7/77:37 pm
DCA
- STL
1 stop5h 16m
Delta
Deal found 6/14![Delta logo]()
$267
This Delta deal was found by Cheapflights users on 6/12. 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.
Wed 7/110:51 am
STL
- IAD
1 stop4h 59m
Delta
Wed 7/85:26 pm
IAD
- STL
1 stop4h 11m
Delta
Deal found 6/12![Delta logo]()
$267
This Kiwi.com deal was found by Cheapflights users on 6/12. 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 7/35:06 pm
STL
- IAD
1 stop15h 53m
Frontier
Tue 7/141:32 pm
IAD
- STL
2 stops20h 25m
Frontier
Deal found 6/12![Frontier logo]()
$264
This Frontier deal was found by Cheapflights users on 6/14. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/67:10 pm
STL
- IAD
1 stop12h 10m
Frontier
Sat 7/111:21 pm
IAD
- STL
1 stop11h 38m
Frontier
Deal found 6/14![Frontier logo]()
$263
This Expedia deal was found by Cheapflights users on 6/14. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/98:08 pm
STL
- DCA
1 stop24h 51m
Frontier
Mon 7/137:00 am
DCA
- STL
1 stop13h 23m
Frontier
Deal found 6/14![Frontier logo]()
$268
This Frontier deal was found by Cheapflights users on 6/11. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/104:57 pm
STL
- IAD
1 stop4h 58m
Frontier
Sun 7/127:49 am
IAD
- STL
1 stop10h 48m
Frontier
Deal found 6/11![Frontier logo]()
$273
This Kiwi.com deal was found by Cheapflights users on 6/14. 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 7/126:34 pm
STL
- IAD
1 stop21h 40m
Frontier
Sun 7/198:33 pm
IAD
- STL
1 stop13h 24m
Frontier
Deal found 6/14![Frontier logo]()
$269
This Southwest deal was found by Cheapflights users on 6/15. 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 7/157:10 pm
STL
- PIT
Nonstop1h 40m
Southwest
Sun 7/197:00 am
PIT
- STL
Nonstop1h 45m
Southwest
Deal found 6/15![Southwest logo]()
$274
This Kiwi.com deal was found by Cheapflights users on 6/11. 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 7/266:34 pm
STL
- IAD
1 stop21h 40m
Frontier
Sun 8/28:33 pm
IAD
- STL
1 stop13h 24m
Frontier
Deal found 6/11![Frontier logo]()
$271
This Southwest deal was found by Cheapflights users on 6/12. 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 7/287:10 pm
STL
- PIT
Nonstop1h 40m
Southwest
Mon 8/37:55 pm
PIT
- STL
1 stop5h 50m
Southwest
Deal found 6/12![Southwest logo]()
$261
This American Airlines deal was found by Cheapflights users on 6/12. 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.
Tue 7/286:55 am
STL
- PIT
1 stop7h 14m
American Airlines
Mon 8/38:49 pm
PIT
- STL
1 stop4h 27m
American Airlines
Deal found 6/12![American Airlines logo]()
$269
One-way flights from St. Louis to PennsylvaniaSearch for one-way flight options from St. Louis to Pennsylvania. Find affordable one-way fares based on user searches. Data last updated June 16, 2026.
Search for one-way flight options from St. Louis to Pennsylvania. Find affordable one-way fares based on user searches. Data last updated June 16, 2026.
This Kiwi.com deal was found by Cheapflights users on 6/14. 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 7/64:57 pm
STL
- IAD
1 stop22h 43m
Frontier
Deal found 6/14![Frontier logo]()
$86
This Southwest deal was found by Cheapflights users on 6/12. 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 9/86:40 pm
STL
- PIT
Nonstop1h 35m
Southwest
Deal found 6/12![Southwest logo]()
$91
This Trip.com deal was found by Cheapflights users on 6/15. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/1210:35 am
STL
- PHL
1 stop6h 40m
Frontier
Deal found 6/15![Frontier logo]()
$93
This Kiwi.com deal was found by Cheapflights users on 6/12. 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 7/35:06 pm
STL
- PHL
1 stop13h 13m
Frontier
Deal found 6/12![Frontier logo]()
$94
This Delta deal was found by Cheapflights users on 6/11. 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.
Wed 8/56:30 am
STL
- PIT
1 stop3h 49m
Delta
Deal found 6/11![Delta logo]()
$95
This Kiwi.com deal was found by Cheapflights users on 6/13. 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 7/104:57 pm
STL
- PHL
1 stop14h 42m
Frontier
Deal found 6/13![Frontier logo]()
$97
This Kiwi.com deal was found by Cheapflights users on 6/13. 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 7/104:57 pm
STL
- IAD
1 stop28h 58m
Frontier
Deal found 6/13![Frontier logo]()
$97
This Kiwi.com deal was found by Cheapflights users on 6/11. 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 7/96:34 pm
STL
- PHL
1 stop26h 59m
Frontier
Deal found 6/11![Frontier logo]()
$99
This WAYA deal was found by Cheapflights users on 6/11. 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 WAYA is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/15:06 pm
STL
- IAD
1 stop5h 11m
Frontier
Deal found 6/11![Frontier logo]()
$100
This Southwest deal was found by Cheapflights users on 6/11. 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 8/53:30 pm
STL
- DCA
Nonstop2h 05m
Southwest
Deal found 6/11![Southwest logo]()
$101
This United Airlines deal was found by Cheapflights users on 6/14. 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.
Tue 8/1112:59 pm
STL
- PIT
1 stop6h 48m
United Airlines
Deal found 6/14![United Airlines logo]()
$101
This Kiwi.com deal was found by Cheapflights users on 6/12. 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 8/34:57 pm
STL
- IAD
1 stop22h 43m
Frontier
Deal found 6/12![Frontier logo]()
$103
Find flight deals from St. Louis to Pennsylvania
Keep the following information in mind while searching for St. Louis to Pennsylvania flight deals. Data was last updated June 16, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $196 (United Airlines) |
One-way from | $86 (Kiwi.com) |
Popular in | November |
Cheapest in | August |
Average price | $458 |
Good round-trip deal | $277 or less |
Good one-way deal | $196 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from St. Louis to Pennsylvania 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 June 16, 2026.
Use the filters below to find and compare flights from St. Louis to Pennsylvania that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
St. LouisPittsburgh
STL - PIT
STLPIT
Lambert-St Louis
Tue 9/1
8:00 am-1:15 pm
1 stop4h 15m
Pittsburgh
Wed 9/30
10:56 am-2:17 pm
1 stop4h 21m
$196
Quickest round-trip
St. LouisPittsburgh
STL - PIT
STLPIT
Lambert-St Louis
Tue 7/28
10:25 am-1:00 pm
Nonstop1h 35m
Pittsburgh
Mon 8/3
8:15 pm-9:00 pm
Nonstop1h 45m
$261
St. LouisWashington, D.C.
STL - DCA
STLDCA
Lambert-St Louis
Fri 9/11
5:00 pm-10:59 pm
1 stop4h 59m
Washington, D.C. Reagan-National
Tue 9/15
11:00 am-3:36 pm
1 stop5h 36m
$264
St. LouisPittsburgh
STL - PIT
STLPIT
Lambert-St Louis
Tue 9/1
6:30 am-11:20 am
1 stop3h 50m
Pittsburgh
Wed 9/30
7:35 am-3:05 pm
2 stops8h 30m
$266
St. LouisWashington, D.C.
STL - IAD
STLIAD
Lambert-St Louis
Fri 7/3
7:12 pm-12:44 am
1 stop4h 32m
Washington, D.C. Dulles Intl
Tue 7/14
8:27 am-12:17 pm
1 stop4h 50m
$267
St. LouisWashington, D.C.
STL - DCA
STLDCA
Lambert-St Louis
Thu 9/24
6:00 am-12:42 pm
1 stop5h 42m
Washington, D.C. Reagan-National
Sat 9/26
12:32 pm-3:14 pm
1 stop3h 42m
$271
St. LouisWashington, D.C.
STL - DCA
STLDCA
Lambert-St Louis
Wed 7/8
7:55 pm-10:55 pm
Nonstop2h 00m
Washington, D.C. Reagan-National
Mon 7/13
6:40 pm-8:00 pm
Nonstop2h 20m
$276
St. LouisPittsburgh
STL - PIT
STLPIT
Lambert-St Louis
Tue 7/28
6:55 am-12:31 pm
1 stop4h 36m
Pittsburgh
Mon 8/3
7:45 pm-11:32 pm
1 stop4h 47m
$285
St. LouisWashington, D.C.
STL - DCA
STLDCA
Lambert-St Louis
Thu 8/27
6:30 am-11:28 am
1 stop3h 58m
Washington, D.C. Reagan-National
Mon 8/31
6:20 am-11:47 am
1 stop6h 27m
$289
St. LouisPittsburgh
STL - PIT
STLPIT
Lambert-St Louis
Sat 9/12
1:25 pm-8:45 pm
2 stops6h 20m
Pittsburgh
Sat 9/19
6:10 am-10:50 am
1 stop5h 40m
$289
Showing 1-10 of 60 resultsSorted by cheapest first
Best time to book a flight from St. Louis to Pennsylvania
Have a flexible travel schedule? Discover the best time to fly to Pennsylvania from St. Louis with our price prediction graph.
STL-PIT
STL-DCA
STL-PHL
STL-IAD
STL-EWR
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 St. Louis to Pennsylvania
STL-USPA
STL-PIT
STL-DCA
STL-PHL
STL-IAD
What is the cheapest month to book a flight from St. Louis to Pennsylvania?
Currently, October is the cheapest month in which you can book a flight from St. Louis to Pennsylvania (average of $76). Flying from St. Louis to Pennsylvania in June is currently the most expensive (average of $185). 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 STL to PA?
Find hourly flight availability from St. Louis to Pennsylvania. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 16, 2026.
It’s optimal to fly from St. Louis to Pennsylvania in the evening. By choosing this option you can save up to 39% on the cost of your flight, compared to a flight at noon.
Weekly flight availability from St. Louis to Pennsylvania
Explore weekly flight availability from St. Louis to Pennsylvania. 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 June 16, 2026.
The most flights from STL to USPA are scheduled on a Monday (9 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (2 on average).
How much does it cost to fly round-trip from St. Louis to Pennsylvania?
How far ahead should I book a flight from St. Louis to Pennsylvania?
To ensure you get the cheapest price possible for a flight from St. Louis to Pennsylvania, you should look to book at least 83 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 St. Louis to Pennsylvania?
Use this chart to determine the cheapest time to fly round-trip from St. Louis to Pennsylvania. Price data was last updated on June 13, 2026.
Travelers seeking maximum savings on their St. Louis to Pennsylvania flight should consider departing on Tuesday evenings when fares are most often at their lowest. Tuesday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.
Reviews of airlines servicing Pennsylvania
Get insights into the airlines that provide service to Pennsylvania. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Pennsylvania. Reviews last updated June 16, 2026.
Get a feel of what it's like to fly with Southwest,Delta, andUnited Airlines from St. Louis to Pennsylvania by reading reviews from past customers. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Overall
7.9
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Overall
7.9
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Overall
7.9
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Overall
7.9
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Overall
7.9
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Entertainment
7.5
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Overall
7.9
Reviews
1 / 20
8.0
ExcellentLa Tracimeldamarcos,Jun 2026
LAX - SLC
Related info for your journey
Find useful and relevant information for your journey from St. Louis to Pennsylvania. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
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Alternative routes for St. Louis to Pennsylvania
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Complete your trip
Complete your trip to Pennsylvania by adding a car rental and/or hotel reservation to your travel itinerary.
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Find flights from St. Louis to Pennsylvania, based on your preferred cabin class, be it economy, premium economy, business, or first class.
St. Louis and Pennsylvania flights
Browse other St. Louis and Pennsylvania flight options. Last updated on June 16, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
St. Louis to Pennsylvania flights
Consider these flights traveling from St. Louis to Pennsylvania.
Top 5 airlines flying from St. Louis to Pennsylvania
Discover the top 5 airlines that operate flights from St. Louis to Pennsylvania. 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 June 16, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$142 | Average$239 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$168 | Average$367 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$204 | Average$362 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$227 | Average$414 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$248 | Average$379 | FlexibilityNo cancel fee | On-timeN/A |