$65+ 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 4/21. Fares are subject to change and may not be available on all flights or dates of travel.
PHL — STL
May 4 — May 111
Round-trip
1 adult, Economy
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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
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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 April 4, 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 April 4, 2026.
This Southwest deal was found by Cheapflights users on 3/31. 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 4/236:55 am
PIT
- STL
Nonstop1h 50m
Southwest
Mon 4/277:40 pm
STL
- PIT
Nonstop1h 35m
Southwest
Deal found 3/31![Southwest logo]()
$217
This Southwest deal was found by Cheapflights users on 4/3. 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 4/297:10 pm
PIT
- STL
Nonstop1h 50m
Southwest
Tue 5/55:40 am
STL
- PIT
1 stop6h 15m
Southwest
Deal found 4/3![Southwest logo]()
$227
This Delta deal was found by Cheapflights users on 4/2. 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 5/211:55 am
PIT
- STL
1 stop4h 44m
Delta
Wed 5/67:25 am
STL
- PIT
1 stop4h 36m
Delta
Deal found 4/2![Delta logo]()
$237
This Southwest deal was found by Cheapflights users on 3/31. 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 5/146:55 am
PIT
- STL
Nonstop1h 50m
Southwest
Sat 5/166:55 pm
STL
- PIT
Nonstop1h 35m
Southwest
Deal found 3/31![Southwest logo]()
$241
This Southwest deal was found by Cheapflights users on 4/3. 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 4/296:05 am
PIT
- STL
2 stops7h 55m
Southwest
Mon 5/45:40 am
STL
- PIT
1 stop3h 20m
Southwest
Deal found 4/3![Southwest logo]()
$242
This Southwest deal was found by Cheapflights users on 4/3. 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 4/296:05 am
PIT
- STL
2 stops7h 55m
Southwest
Thu 4/3010:15 am
STL
- PIT
2 stops6h 55m
Southwest
Deal found 4/3![Southwest logo]()
$247
This Expedia deal was found by Cheapflights users on 3/30. 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 4/210:06 pm
MDT
- STL
1 stop10h 22m
Frontier
Sat 4/48:41 am
STL
- MDT
1 stop11h 40m
Frontier
Deal found 3/30![Frontier logo]()
$250
This Southwest deal was found by Cheapflights users on 3/31. 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 5/16:55 am
PIT
- STL
Nonstop1h 50m
Southwest
Mon 5/410:15 am
STL
- PIT
Nonstop1h 40m
Southwest
Deal found 3/31![Southwest logo]()
$262
This Southwest deal was found by Cheapflights users on 3/30. 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 4/276:55 am
PIT
- STL
Nonstop1h 50m
Southwest
Wed 4/296:45 pm
STL
- PIT
Nonstop1h 35m
Southwest
Deal found 3/30![Southwest logo]()
$265
This Kiwi.com deal was found by Cheapflights users on 4/3. 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 4/216:35 am
PIT
- STL
2 stops25h 15m
Multiple Airlines
Thu 4/234:59 pm
STL
- PIT
1 stop15h 00m
Multiple Airlines
Deal found 4/3![Multiple Airlines logo]()
$266
This Kiwi.com deal was found by Cheapflights users on 4/2. 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 5/16:15 pm
PIT
- STL
2 stops13h 35m
Multiple Airlines
Fri 5/84:19 pm
STL
- PIT
1 stop26h 01m
Multiple Airlines
Deal found 4/2![Multiple Airlines logo]()
$268
This Southwest deal was found by Cheapflights users on 4/3. 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 5/73:00 pm
DCA
- STL
1 stop4h 55m
Southwest
Mon 5/113:45 pm
STL
- DCA
Nonstop2h 00m
Southwest
Deal found 4/3![Southwest logo]()
$275
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 April 4, 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 April 4, 2026.
This Southwest deal was found by Cheapflights users on 4/4. 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 4/252:45 pm
PIT
- STL
2 stops8h 20m
Southwest
Mon 4/277:40 pm
STL
- PIT
Nonstop1h 35m
Southwest
Deal found 4/4![Southwest logo]()
$232
This Delta deal was found by Cheapflights users on 4/3. 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 4/2711:55 am
PIT
- STL
1 stop6h 49m
Delta
Wed 5/66:48 am
STL
- PIT
1 stop5h 34m
Delta
Deal found 4/3![Delta logo]()
$237
This United Airlines deal was found by Cheapflights users on 4/1. 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.
Thu 5/73:15 pm
IAD
- STL
1 stop6h 58m
United Airlines
Sat 5/98:45 am
STL
- IAD
Nonstop2h 10m
United Airlines
Deal found 4/1![United Airlines logo]()
$288
This Kiwi.com deal was found by Cheapflights users on 3/30. 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 4/276:30 am
ABE
- STL
1 stop17h 49m
Multiple Airlines
Mon 5/43:21 pm
STL
- ABE
2 stops19h 06m
Multiple Airlines
Deal found 3/30![Multiple Airlines logo]()
$322
This American Airlines deal was found by Cheapflights users on 4/4. 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 5/296:22 am
ABE
- STL
1 stop6h 37m
American Airlines
Mon 6/16:12 pm
STL
- ABE
1 stop5h 09m
American Airlines
Deal found 4/4![American Airlines logo]()
$439
This Southwest deal was found by Cheapflights users on 3/30. 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 4/276:45 pm
PIT
- STL
1 stop5h 55m
Southwest
Wed 4/296:45 pm
STL
- PIT
Nonstop1h 35m
Southwest
Deal found 3/30![Southwest logo]()
$275
This Delta deal was found by Cheapflights users on 3/30. 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 4/3010:20 am
PIT
- STL
1 stop6h 12m
Delta
Tue 5/54:41 pm
STL
- PIT
1 stop3h 55m
Delta
Deal found 3/30![Delta logo]()
$275
This Delta deal was found by Cheapflights users on 3/30. 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 4/277:46 pm
PIT
- STL
1 stop4h 50m
Delta
Wed 4/2910:50 am
STL
- PIT
1 stop3h 25m
Delta
Deal found 3/30![Delta logo]()
$275
This Southwest deal was found by Cheapflights users on 3/31. 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 4/276:45 pm
DCA
- STL
Nonstop2h 25m
Southwest
Thu 4/3010:15 am
STL
- DCA
2 stops6h 50m
Southwest
Deal found 3/31![Southwest logo]()
$280
This United Airlines deal was found by Cheapflights users on 4/2. 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 5/165:54 pm
MDT
- STL
1 stop6h 25m
United Airlines
Mon 5/187:09 pm
STL
- MDT
1 stop4h 46m
United Airlines
Deal found 4/2![United Airlines logo]()
$310
This Delta deal was found by Cheapflights users on 3/30. 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 5/274:45 pm
PIT
- STL
1 stop5h 44m
Delta
Sun 5/317:01 pm
STL
- PIT
1 stop4h 44m
Delta
Deal found 3/30![Delta logo]()
$276
This Southwest deal was found by Cheapflights users on 4/1. 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 6/16:45 pm
PIT
- STL
1 stop5h 55m
Southwest
Fri 6/54:35 pm
STL
- PIT
2 stops5h 55m
Southwest
Deal found 4/1![Southwest logo]()
$287
This United Airlines deal was found by Cheapflights users on 4/3. 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.
Sun 5/245:36 pm
ABE
- STL
1 stop4h 40m
United Airlines
Sat 5/306:00 am
STL
- ABE
1 stop6h 48m
United Airlines
Deal found 4/3![United Airlines logo]()
$329
This Delta deal was found by Cheapflights users on 3/31. 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 5/23:00 pm
IAD
- STL
1 stop5h 11m
Delta
Sat 5/166:00 am
STL
- IAD
1 stop4h 50m
Delta
Deal found 3/31![Delta logo]()
$285
This Southwest deal was found by Cheapflights users on 4/1. 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 5/136:50 pm
DCA
- STL
Nonstop2h 25m
Southwest
Fri 5/157:40 pm
STL
- DCA
Nonstop2h 00m
Southwest
Deal found 4/1![Southwest logo]()
$287
This United Airlines deal was found by Cheapflights users on 4/1. 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 5/295:50 pm
MDT
- STL
1 stop4h 26m
United Airlines
Sun 5/319:23 am
STL
- MDT
1 stop6h 31m
United Airlines
Deal found 4/1![United Airlines logo]()
$334
This Delta deal was found by Cheapflights users on 3/30. 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 4/277:38 pm
DCA
- STL
1 stop4h 58m
Delta
Thu 4/3012:45 pm
STL
- DCA
1 stop5h 07m
Delta
Deal found 3/30![Delta logo]()
$285
This Southwest deal was found by Cheapflights users on 4/2. 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 6/236:45 am
PIT
- STL
Nonstop1h 45m
Southwest
Mon 6/2910:00 am
STL
- PIT
1 stop3h 50m
Southwest
Deal found 4/2![Southwest logo]()
$290
This United Airlines deal was found by Cheapflights users on 4/3. 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 5/53:30 pm
DCA
- STL
1 stop6h 43m
United Airlines
Wed 5/66:15 am
STL
- DCA
1 stop5h 15m
United Airlines
Deal found 4/3![United Airlines logo]()
$337
This Southwest deal was found by Cheapflights users on 3/30. 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 6/33:05 pm
LGA
- STL
Nonstop2h 55m
Southwest
Sat 6/68:00 pm
STL
- LGA
Nonstop2h 25m
Southwest
Deal found 3/30![Southwest logo]()
$296
This Delta deal was found by Cheapflights users on 4/1. 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 5/217:59 am
DCA
- STL
1 stop5h 21m
Delta
Tue 5/266:04 pm
STL
- DCA
1 stop3h 55m
Delta
Deal found 4/1![Delta logo]()
$296
This United Airlines deal was found by Cheapflights users on 3/30. 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.
Thu 4/235:52 pm
MDT
- STL
1 stop4h 21m
United Airlines
Sun 4/269:10 am
STL
- MDT
1 stop6h 41m
United Airlines
Deal found 3/30![United Airlines logo]()
$339
This American Airlines deal was found by Cheapflights users on 4/2. 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.
Sat 4/1811:32 am
SCE
- STL
2 stops10h 53m
American Airlines
Thu 4/309:56 am
STL
- SCE
2 stops8h 09m
American Airlines
Deal found 4/2![American Airlines logo]()
$499
This Southwest deal was found by Cheapflights users on 4/4. 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 5/195:30 pm
LGA
- STL
Nonstop2h 55m
Southwest
Sat 5/2310:35 am
STL
- LGA
2 stops8h 15m
Southwest
Deal found 4/4![Southwest logo]()
$309
This Delta deal was found by Cheapflights users on 4/3. 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 6/275:34 pm
MDT
- STL
1 stop4h 05m
Delta
Mon 6/293:45 pm
STL
- MDT
1 stop7h 10m
Delta
Deal found 4/3![Delta logo]()
$310
This American Airlines deal was found by Cheapflights users on 4/3. 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 5/147:31 pm
SCE
- STL
2 stops13h 56m
American Airlines
Tue 5/193:24 pm
STL
- SCE
2 stops7h 02m
American Airlines
Deal found 4/3![American Airlines logo]()
$515
This United Airlines deal was found by Cheapflights users on 4/2. 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 7/35:00 pm
DCA
- STL
1 stop5h 26m
United Airlines
Fri 7/101:13 pm
STL
- DCA
1 stop4h 57m
United Airlines
Deal found 4/2![United Airlines logo]()
$357
This Delta deal was found by Cheapflights users on 3/31. 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 8/2112:25 pm
MDT
- STL
1 stop4h 32m
Delta
Tue 8/255:30 pm
STL
- MDT
1 stop5h 10m
Delta
Deal found 3/31![Delta logo]()
$310
This Southwest deal was found by Cheapflights users on 4/3. 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 5/297:45 pm
DCA
- STL
1 stop4h 00m
Southwest
Mon 6/17:40 pm
STL
- DCA
Nonstop2h 00m
Southwest
Deal found 4/3![Southwest logo]()
$311
This United Airlines deal was found by Cheapflights users on 3/30. 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 5/25:40 pm
SCE
- STL
1 stop6h 39m
United Airlines
Tue 5/58:45 am
STL
- SCE
1 stop4h 22m
United Airlines
Deal found 3/30![United Airlines logo]()
$371
Last-minute flights from Pennsylvania to St. LouisDiscover last-minute flight deals from Pennsylvania to St. Louis. Data last updated April 4, 2026 and is based on user searches.
Discover last-minute flight deals from Pennsylvania to St. Louis. Data last updated April 4, 2026 and is based on user searches.
This Expedia deal was found by Cheapflights users on 3/30. 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 4/210:06 pm
MDT
- STL
1 stop10h 22m
Frontier
Sat 4/48:41 am
STL
- MDT
1 stop11h 40m
Frontier
Deal found 3/30![Frontier logo]()
$250
This Kiwi.com deal was found by Cheapflights users on 4/3. 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 4/216:35 am
PIT
- STL
2 stops25h 15m
Multiple Airlines
Thu 4/234:59 pm
STL
- PIT
1 stop15h 00m
Multiple Airlines
Deal found 4/3![Multiple Airlines logo]()
$266
This Southwest deal was found by Cheapflights users on 3/31. 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 4/236:55 am
PIT
- STL
Nonstop1h 50m
Southwest
Mon 4/277:40 pm
STL
- PIT
Nonstop1h 35m
Southwest
Deal found 3/31![Southwest logo]()
$217
This Southwest deal was found by Cheapflights users on 3/30. 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 4/276:55 am
PIT
- STL
Nonstop1h 50m
Southwest
Wed 4/296:45 pm
STL
- PIT
Nonstop1h 35m
Southwest
Deal found 3/30![Southwest logo]()
$265
This Southwest deal was found by Cheapflights users on 4/3. 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 4/297:10 pm
PIT
- STL
Nonstop1h 50m
Southwest
Tue 5/55:40 am
STL
- PIT
1 stop6h 15m
Southwest
Deal found 4/3![Southwest logo]()
$227
This Southwest deal was found by Cheapflights users on 4/3. 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 4/296:05 am
PIT
- STL
2 stops7h 55m
Southwest
Mon 5/45:40 am
STL
- PIT
1 stop3h 20m
Southwest
Deal found 4/3![Southwest logo]()
$242
This Southwest deal was found by Cheapflights users on 4/3. 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 4/296:05 am
PIT
- STL
2 stops7h 55m
Southwest
Thu 4/3010:15 am
STL
- PIT
2 stops6h 55m
Southwest
Deal found 4/3![Southwest logo]()
$247
This Southwest deal was found by Cheapflights users on 3/31. 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 5/16:55 am
PIT
- STL
Nonstop1h 50m
Southwest
Mon 5/410:15 am
STL
- PIT
Nonstop1h 40m
Southwest
Deal found 3/31![Southwest logo]()
$262
This Kiwi.com deal was found by Cheapflights users on 4/2. 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 5/16:15 pm
PIT
- STL
2 stops13h 35m
Multiple Airlines
Fri 5/84:19 pm
STL
- PIT
1 stop26h 01m
Multiple Airlines
Deal found 4/2![Multiple Airlines logo]()
$268
This Delta deal was found by Cheapflights users on 4/2. 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 5/211:55 am
PIT
- STL
1 stop4h 44m
Delta
Wed 5/67:25 am
STL
- PIT
1 stop4h 36m
Delta
Deal found 4/2![Delta logo]()
$237
This Southwest deal was found by Cheapflights users on 3/31. 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 5/146:55 am
PIT
- STL
Nonstop1h 50m
Southwest
Sat 5/166:55 pm
STL
- PIT
Nonstop1h 35m
Southwest
Deal found 3/31![Southwest logo]()
$241
This Delta deal was found by Cheapflights users on 4/4. 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 5/199:00 am
DCA
- STL
1 stop4h 22m
Delta
Thu 5/219:30 am
STL
- DCA
1 stop5h 50m
Delta
Deal found 4/4![Delta logo]()
$271
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 April 4, 2026.
Search for one-way flight options from Pennsylvania to St. Louis. Find affordable one-way fares based on user searches. Data last updated April 4, 2026.
This Kiwi.com deal was found by Cheapflights users on 4/1. 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 4/218:20 am
IAD
- STL
1 stop23h 30m
Frontier
Deal found 4/1![Frontier logo]()
$65
This Trip.com deal was found by Cheapflights users on 3/31. 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.
Tue 4/1410:29 pm
EWR
- STL
1 stop9h 21m
Frontier
Deal found 3/31![Frontier logo]()
$68
This Super.com deal was found by Cheapflights users on 3/31. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/1610:40 am
PHL
- STL
1 stop10h 43m
Frontier
Deal found 3/31![Frontier logo]()
$69
This Frontier deal was found by Cheapflights users on 3/31. 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.
Sun 4/266:20 am
IAD
- STL
1 stop5h 29m
Frontier
Deal found 3/31![Frontier logo]()
$70
This Frontier deal was found by Cheapflights users on 4/1. 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.
Sat 5/24:42 pm
PHL
- STL
1 stop7h 37m
Frontier
Deal found 4/1![Frontier logo]()
$70
This Trip.com deal was found by Cheapflights users on 3/31. 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.
Tue 4/145:39 pm
EWR
- STL
1 stop14h 11m
Multiple Airlines
Deal found 3/31![Multiple Airlines logo]()
$71
This Super.com deal was found by Cheapflights users on 3/31. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/306:43 am
PHL
- STL
1 stop15h 17m
Frontier
Deal found 3/31![Frontier logo]()
$75
This Booking.com deal was found by Cheapflights users on 4/3. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/48:12 am
IAD
- STL
1 stop16h 07m
Frontier
Deal found 4/3![Frontier logo]()
$76
This Priceline deal was found by Cheapflights users on 4/1. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/110:29 pm
EWR
- STL
1 stop9h 21m
Frontier
Deal found 4/1![Frontier logo]()
$76
This Booking.com deal was found by Cheapflights users on 3/31. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/235:05 am
PHL
- STL
1 stop19h 14m
Frontier
Deal found 3/31![Frontier logo]()
$76
This Frontier deal was found by Cheapflights users on 4/2. 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.
Sat 4/2512:44 pm
PIT
- STL
1 stop11h 35m
Frontier
Deal found 4/2![Frontier logo]()
$77
This Kiwi.com deal was found by Cheapflights users on 4/1. 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 5/37:00 am
PHL
- STL
1 stop24h 50m
Multiple Airlines
Deal found 4/1![Multiple Airlines logo]()
$80
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 April 4, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $217 (Southwest) |
One-way from | $65 (Kiwi.com) |
Popular in | May |
Cheapest in | September |
Average price | $404 |
Good round-trip deal | $349 or less |
Good one-way deal | $172 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 April 4, 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
PittsburghSt. Louis
PIT - STL
PITSTL
Pittsburgh
Sat 4/25
2:45 pm-10:05 pm
2 stops8h 20m
Lambert-St Louis
Mon 4/27
7:40 pm-10:15 pm
Nonstop1h 35m
$232
PittsburghSt. Louis
PIT - STL
PITSTL
Pittsburgh
Mon 4/27
11:55 am-5:44 pm
1 stop6h 49m
Lambert-St Louis
Wed 5/6
6:48 am-1:22 pm
1 stop5h 34m
$237
PittsburghSt. Louis
PIT - STL
PITSTL
Pittsburgh
Mon 4/27
6:45 pm-11:40 pm
1 stop5h 55m
Lambert-St Louis
Wed 4/29
6:45 pm-9:20 pm
Nonstop1h 35m
$275
PittsburghSt. Louis
PIT - STL
PITSTL
Pittsburgh
Thu 4/30
10:20 am-3:32 pm
1 stop6h 12m
Lambert-St Louis
Tue 5/5
4:41 pm-9:36 pm
1 stop3h 55m
$275
PittsburghSt. Louis
PIT - STL
PITSTL
Pittsburgh
Mon 4/27
7:46 pm-11:36 pm
1 stop4h 50m
Lambert-St Louis
Wed 4/29
10:50 am-3:15 pm
1 stop3h 25m
$275
PittsburghSt. Louis
PIT - STL
PITSTL
Pittsburgh
Wed 5/27
4:45 pm-9:29 pm
1 stop5h 44m
Lambert-St Louis
Sun 5/31
7:01 pm-12:45 am
1 stop4h 44m
$276
Washington, D.C.St. Louis
DCA - STL
DCASTL
Washington, D.C. Reagan-National
Mon 4/27
6:45 pm-8:10 pm
Nonstop2h 25m
Lambert-St Louis
Thu 4/30
10:15 am-6:05 pm
2 stops6h 50m
$280
Washington, D.C.St. Louis
IAD - STL
IADSTL
Washington, D.C. Dulles Intl
Sat 5/2
3:00 pm-7:11 pm
1 stop5h 11m
Lambert-St Louis
Sat 5/16
6:00 am-11:50 am
1 stop4h 50m
$285
Washington, D.C.St. Louis
DCA - STL
DCASTL
Washington, D.C. Reagan-National
Mon 4/27
7:38 pm-11:36 pm
1 stop4h 58m
Lambert-St Louis
Thu 4/30
12:45 pm-6:52 pm
1 stop5h 07m
$285
PittsburghSt. Louis
PIT - STL
PITSTL
Pittsburgh
Mon 6/1
6:45 pm-11:40 pm
1 stop5h 55m
Lambert-St Louis
Fri 6/5
4:35 pm-11:30 pm
2 stops5h 55m
$287
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
MDT-STL
DCA-STL
IAD-STL
EWR-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
MDT-STL
DCA-STL
IAD-STL
What is the cheapest month to book a flight from Pennsylvania to St. Louis?
Currently, November is the cheapest month in which you can book a flight from Pennsylvania to St. Louis (average of $156). Flying from Pennsylvania to St. Louis in March is currently the most expensive (average of $277). 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 April 4, 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 13% versus a flight in the morning.
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 April 4, 2026.
Travelers seeking maximum savings on their Pennsylvania to St. Louis flight should consider departing on Tuesday afternoons 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.
How much does it cost to fly round-trip from Pennsylvania to St. Louis?
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
O'Fallon
Fenton
Swansea
Fairview Heights
Maryland Heights
Collinsville
Eureka
Wentzville
Glencoe
Chesterfield
Alton
Farmington
Festus
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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.
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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 April 4, 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 April 4, 2026.
Pennsylvania to St. Louis flights
Consider these flights traveling from Pennsylvania to St. Louis.
Top 6 airlines flying from Pennsylvania to St. Louis
Discover the top 6 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 April 4, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$93 | Average$178 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$135 | Average$215 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$170 | Average$336 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$221 | Average$382 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$248 | Average$382 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$248 | Average$389 | FlexibilityNo cancel fee | On-time69% |