$67+ 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 9/11. Fares are subject to change and may not be available on all flights or dates of travel.
STL — PHL
Sep 7 — Sep 141
Round-trip
1 adult, Economy
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Find cheap flights from St. Louis to Pennsylvania 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 St. Louis to Pennsylvania
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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 August 8, 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 August 8, 2026.
This Kiwi.com deal was found by Cheapflights users on 8/2. 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.
Mon 9/76:17 pm -
1 stop11h 58m
Thu 9/1012:40 pm -
1 stop25h 30m
Deal found 8/2![Frontier logo]()
$147
This Kiwi.com deal was found by Cheapflights users on 8/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/142:29 pm -
1 stop7h 49m
Mon 9/218:41 am -
1 stop5h 29m
Deal found 8/4![Frontier logo]()
$151
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Thu 11/510:35 am -
1 stop6h 40m
Sun 11/85:28 pm -
1 stop17h 12m
Deal found 8/3![Frontier logo]()
$152
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Fri 10/22:29 pm -
1 stop7h 49m
Sun 10/45:32 pm -
1 stop20h 38m
Deal found 8/3![Frontier logo]()
$154
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.
Fri 10/1610:35 am -
1 stop6h 40m
Sun 10/187:10 am -
1 stop27h 30m
Deal found 8/5![Frontier logo]()
$158
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Thu 10/1510:35 am -
1 stop20h 01m
Mon 10/195:38 pm -
1 stop17h 02m
Deal found 8/3![Frontier logo]()
$160
This Kiwi.com deal was found by Cheapflights users on 8/3. 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 10/1310:35 am -
1 stop6h 40m
Sun 10/185:38 pm -
1 stop17h 02m
Deal found 8/3![Frontier logo]()
$162
This Kiwi.com deal was found by Cheapflights users on 8/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/510:35 am -
1 stop25h 37m
Mon 11/95:28 pm -
1 stop17h 12m
Deal found 8/4![Frontier logo]()
$165
This Kiwi.com deal was found by Cheapflights users on 8/3. 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 10/1310:35 am -
1 stop6h 40m
Sat 10/175:38 pm -
1 stop17h 02m
Deal found 8/3![Frontier logo]()
$167
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.
Mon 10/1210:35 am -
1 stop20h 01m
Mon 10/195:38 pm -
1 stop17h 02m
Deal found 8/5![Frontier logo]()
$168
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Fri 8/286:17 pm -
1 stop11h 58m
Mon 8/318:30 am -
1 stop9h 52m
Deal found 8/3![Frontier logo]()
$173
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Sun 8/236:17 pm -
1 stop11h 58m
Mon 8/318:30 am -
1 stop9h 52m
Deal found 8/3![Frontier logo]()
$174
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 August 8, 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 August 8, 2026.
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 10/157:55 pm -
Nonstop1h 35m
Tue 10/206:50 am -
Nonstop1h 55m
Deal found 8/7![Southwest logo]()
$207
This United Airlines deal was found by Cheapflights users on 8/3. 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.
Wed 8/268:00 am -
1 stop4h 15m
Fri 8/286:09 pm -
1 stop4h 52m
Deal found 8/3![United Airlines logo]()
$232
This Delta deal was found by Cheapflights users on 8/3. 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.
Fri 10/26:54 pm -
1 stop4h 37m
Sun 10/45:50 am -
1 stop6h 05m
Deal found 8/3![Delta logo]()
$257
This American Airlines deal was found by Cheapflights users on 8/2. 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.
Thu 10/1510:48 am -
Nonstop2h 11m
Mon 10/192:25 pm -
Nonstop2h 32m
Deal found 8/2![American Airlines logo]()
$275
This Southwest deal was found by Cheapflights users on 8/3. 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 9/96:50 pm -
Nonstop1h 40m
Fri 9/117:20 pm -
Nonstop1h 40m
Deal found 8/3![Southwest logo]()
$212
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.
Fri 10/2310:20 am -
Nonstop1h 35m
Mon 10/268:20 pm -
Nonstop1h 40m
Deal found 8/7![Southwest logo]()
$227
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.
Fri 9/117:35 pm -
Nonstop1h 45m
Mon 9/147:20 pm -
Nonstop1h 40m
Deal found 8/5![Southwest logo]()
$241
This Delta deal was found by Cheapflights users on 8/4. 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.
Sat 9/57:05 am -
Nonstop2h 30m
Sun 9/61:50 pm -
Nonstop2h 48m
Deal found 8/4![Delta logo]()
$293
This American Airlines deal was found by Cheapflights users on 8/2. 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 10/31:25 pm -
Nonstop2h 23m
Tue 10/63:23 pm -
Nonstop2h 45m
Deal found 8/2![American Airlines logo]()
$309
This United Airlines deal was found by Cheapflights users on 8/2. 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.
Tue 9/110:53 am -
1 stop5h 07m
Tue 9/85:36 pm -
1 stop5h 24m
Deal found 8/2![United Airlines logo]()
$314
This Delta deal was found by Cheapflights users on 8/3. 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 11/236:00 pm -
1 stop4h 28m
Thu 12/39:40 am -
1 stop4h 43m
Deal found 8/3![Delta logo]()
$295
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/2410:30 am -
Nonstop1h 35m
Mon 10/266:50 am -
Nonstop1h 55m
Deal found 8/6![Southwest logo]()
$255
This United Airlines deal was found by Cheapflights users on 8/4. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/48:00 am -
1 stop4h 55m
Mon 9/78:25 am -
Nonstop2h 14m
Deal found 8/4![United Airlines logo]()
$317
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 9/36:00 am -
1 stop5h 45m
Mon 9/77:31 pm -
1 stop5h 43m
Deal found 8/5![American Airlines logo]()
$319
This Delta deal was found by Cheapflights users on 8/2. 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.
Tue 10/67:20 pm -
1 stop4h 22m
Sat 10/106:05 am -
1 stop4h 39m
Deal found 8/2![Delta logo]()
$295
This Alaska 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 Alaska Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/47:00 am -
2 stops22h 36m
Sat 11/75:29 pm -
2 stops21h 46m
Deal found 8/7![Alaska Airlines logo]()
$733
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/1710:30 am -
Nonstop1h 35m
Tue 10/206:50 am -
Nonstop1h 55m
Deal found 8/6![Southwest logo]()
$255
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/306:00 am -
1 stop4h 30m
Sat 10/312:18 pm -
1 stop3h 56m
Deal found 8/5![Delta logo]()
$299
This United Airlines deal was found by Cheapflights users on 8/2. 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.
Sun 8/306:54 pm -
1 stop4h 50m
Mon 8/316:16 am -
1 stop6h 01m
Deal found 8/2![United Airlines logo]()
$331
This American Airlines deal was found by Cheapflights users on 8/2. 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 10/35:18 pm -
1 stop5h 41m
Sat 10/106:01 am -
1 stop7h 34m
Deal found 8/2![American Airlines logo]()
$357
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.
Wed 10/146:00 am -
1 stop7h 08m
Wed 10/146:12 pm -
1 stop6h 42m
Deal found 8/7![Delta logo]()
$299
This United Airlines deal was found by Cheapflights users on 8/3. 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 9/67:25 am -
1 stop4h 58m
Thu 9/108:05 am -
1 stop4h 52m
Deal found 8/3![United Airlines logo]()
$332
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/31:10 pm -
Nonstop2h 00m
Tue 9/86:50 pm -
Nonstop2h 10m
Deal found 8/6![Southwest logo]()
$279
This United Airlines deal was found by Cheapflights users on 8/3. 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.
Wed 9/98:40 am -
Nonstop2h 14m
Sun 9/138:25 am -
Nonstop2h 14m
Deal found 8/3![United Airlines logo]()
$332
This Delta deal was found by Cheapflights users on 8/3. 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.
Sun 9/65:25 pm -
Nonstop2h 38m
Thu 9/109:59 am -
Nonstop2h 44m
Deal found 8/3![Delta logo]()
$312
This Southwest deal was found by Cheapflights users on 8/3. 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.
Mon 9/143:45 pm -
1 stop6h 35m
Mon 9/213:30 pm -
Nonstop2h 15m
Deal found 8/3![Southwest logo]()
$285
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.
Thu 8/278:40 am -
1 stop4h 23m
Tue 9/15:54 pm -
1 stop5h 06m
Deal found 8/7![United Airlines logo]()
$334
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 9/53:44 pm -
1 stop5h 16m
Sun 9/611:00 am -
1 stop6h 17m
Deal found 8/6![Delta logo]()
$313
This Southwest deal was found by Cheapflights users on 8/3. 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 9/176:15 pm -
1 stop4h 40m
Thu 9/2412:15 pm -
Nonstop2h 10m
Deal found 8/3![Southwest logo]()
$285
This KAYAK 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 KAYAK is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/246:00 am -
1 stop7h 55m
Tue 8/256:30 am -
1 stop4h 44m
Deal found 8/7![American Airlines logo]()
$437
Last-minute flights from St. Louis to PennsylvaniaDiscover last-minute flight deals from St. Louis to Pennsylvania. Data last updated August 8, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Pennsylvania. Data last updated August 8, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Sun 8/236:17 pm -
1 stop11h 58m
Mon 8/318:30 am -
1 stop9h 52m
Deal found 8/3![Frontier logo]()
$174
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Sun 8/236:17 pm -
1 stop11h 58m
Fri 8/286:30 am -
1 stop11h 52m
Deal found 8/3![Frontier logo]()
$178
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Sun 8/236:17 pm -
1 stop11h 58m
Sun 8/308:30 am -
1 stop9h 52m
Deal found 8/3![Frontier logo]()
$183
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Mon 8/246:17 pm -
1 stop11h 58m
Mon 8/318:30 am -
1 stop9h 52m
Deal found 8/3![Frontier logo]()
$177
This Kiwi.com deal was found by Cheapflights users on 8/2. 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.
Mon 8/246:17 pm -
1 stop17h 09m
Fri 8/288:30 am -
1 stop9h 52m
Deal found 8/2![Frontier logo]()
$179
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Mon 8/246:17 pm -
1 stop11h 58m
Sun 8/308:30 am -
1 stop9h 52m
Deal found 8/3![Frontier logo]()
$186
This Kiwi.com deal was found by Cheapflights users on 8/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 8/276:17 pm -
1 stop11h 58m
Mon 8/318:30 am -
1 stop9h 52m
Deal found 8/4![Frontier logo]()
$182
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Fri 8/286:17 pm -
1 stop11h 58m
Mon 8/318:30 am -
1 stop9h 52m
Deal found 8/3![Frontier logo]()
$173
This Kiwi.com deal was found by Cheapflights users on 8/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/36:17 pm -
1 stop17h 09m
Thu 9/1012:40 pm -
1 stop25h 30m
Deal found 8/4![Frontier logo]()
$188
This Southwest deal was found by Cheapflights users on 8/3. 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 9/310:30 am -
Nonstop1h 40m
Wed 9/97:20 pm -
Nonstop1h 40m
Deal found 8/3![Southwest logo]()
$197
This Kiwi.com deal was found by Cheapflights users on 8/2. 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.
Mon 9/76:17 pm -
1 stop11h 58m
Thu 9/1012:40 pm -
1 stop25h 30m
Deal found 8/2![Frontier logo]()
$147
This Kiwi.com deal was found by Cheapflights users on 8/4. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/142:29 pm -
1 stop7h 49m
Mon 9/218:41 am -
1 stop5h 29m
Deal found 8/4![Frontier logo]()
$151
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 August 8, 2026.
Search for one-way flight options from St. Louis to Pennsylvania. Find affordable one-way fares based on user searches. Data last updated August 8, 2026.
This Trip.com deal was found by Cheapflights users on 8/3. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/112:29 pm -
1 stop8h 41m
Deal found 8/3![Frontier logo]()
$67
This Kiwi.com deal was found by Cheapflights users on 8/2. 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.
Mon 9/142:29 pm -
1 stop8h 41m
Deal found 8/2![Frontier logo]()
$68
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 10/52:29 pm -
1 stop26h 45m
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.
Mon 10/2610:35 am -
1 stop20h 01m
Deal found 8/7![Frontier logo]()
$71
This Kiwi.com deal was found by Cheapflights users on 8/3. 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.
Thu 11/510:35 am -
1 stop25h 37m
Deal found 8/3![Frontier logo]()
$75
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.
Fri 10/3010:35 am -
1 stop20h 01m
Deal found 8/7![Frontier logo]()
$76
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 10/2910:35 am -
2 stops13h 03m
Deal found 8/7![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 9/36:17 pm -
1 stop17h 09m
Deal found 8/5![Frontier logo]()
$78
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 10/2210:35 am -
1 stop6h 40m
Deal found 8/5![Frontier logo]()
$79
This Kiwi.com deal was found by Cheapflights users on 8/2. 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.
Sun 11/110:35 am -
1 stop20h 01m
Deal found 8/2![Frontier logo]()
$81
This Trip.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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/46:17 pm -
1 stop17h 09m
Deal found 8/5![Frontier logo]()
$82
This Trip.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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/1410:35 am -
1 stop6h 01m
Deal found 8/7![Frontier logo]()
$83
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 August 8, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $147 (Kiwi.com) |
One-way from | $67 (Trip.com) |
Popular in | November |
Cheapest in | September |
Average price | $368 |
Good round-trip deal | $299 or less |
Good one-way deal | $149 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 August 8, 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 Lambert-St Louis - PIT Pittsburgh
STLPIT
Lambert-St Louis
Thu 10/15
7:55 pm-10:30 pm
Nonstop1h 35m
Pittsburgh
Tue 10/20
6:50 am-7:45 am
Nonstop1h 55m
$207
St. LouisPittsburgh
STL Lambert-St Louis - PIT Pittsburgh
STLPIT
Lambert-St Louis
Wed 9/9
6:50 pm-9:30 pm
Nonstop1h 40m
Pittsburgh
Fri 9/11
7:20 pm-8:00 pm
Nonstop1h 40m
$212
Quickest round-trip
St. LouisPittsburgh
STL Lambert-St Louis - PIT Pittsburgh
STLPIT
Lambert-St Louis
Fri 10/23
10:20 am-12:55 pm
Nonstop1h 35m
Pittsburgh
Mon 10/26
8:20 pm-9:00 pm
Nonstop1h 40m
$227
St. LouisPittsburgh
STL Lambert-St Louis - PIT Pittsburgh
STLPIT
Lambert-St Louis
Wed 8/26
8:00 am-1:15 pm
1 stop4h 15m
Pittsburgh
Fri 8/28
6:09 pm-10:01 pm
1 stop4h 52m
$232
St. LouisPittsburgh
STL Lambert-St Louis - PIT Pittsburgh
STLPIT
Lambert-St Louis
Fri 9/11
7:35 pm-10:20 pm
Nonstop1h 45m
Pittsburgh
Mon 9/14
7:20 pm-8:00 pm
Nonstop1h 40m
$241
St. LouisPittsburgh
STL Lambert-St Louis - PIT Pittsburgh
STLPIT
Lambert-St Louis
Sat 10/24
10:30 am-1:05 pm
Nonstop1h 35m
Pittsburgh
Mon 10/26
6:50 am-7:45 am
Nonstop1h 55m
$255
St. LouisPittsburgh
STL Lambert-St Louis - PIT Pittsburgh
STLPIT
Lambert-St Louis
Sat 10/17
10:30 am-1:05 pm
Nonstop1h 35m
Pittsburgh
Tue 10/20
6:50 am-7:45 am
Nonstop1h 55m
$255
St. LouisPittsburgh
STL Lambert-St Louis - PIT Pittsburgh
STLPIT
Lambert-St Louis
Fri 10/2
6:54 pm-12:31 am
1 stop4h 37m
Pittsburgh
Sun 10/4
5:50 am-10:55 am
1 stop6h 05m
$257
St. LouisWashington, D.C.
STL Lambert-St Louis - DCA Washington, D.C. Reagan-National
STLDCA
Lambert-St Louis
Thu 10/15
10:48 am-1:59 pm
Nonstop2h 11m
Washington, D.C. Reagan-National
Mon 10/19
2:25 pm-3:57 pm
Nonstop2h 32m
$275
St. LouisWashington, D.C.
STL Lambert-St Louis - DCA Washington, D.C. Reagan-National
STLDCA
Lambert-St Louis
Thu 9/3
1:10 pm-4:10 pm
Nonstop2h 00m
Washington, D.C. Reagan-National
Tue 9/8
6:50 pm-8:00 pm
Nonstop2h 10m
$279
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-PHL
STL-PIT
STL-IAD
STL-MDT
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-PHL
STL-PIT
STL-IAD
STL-MDT
What is the cheapest month to book a flight from St. Louis to Pennsylvania?
Currently, September is the cheapest month in which you can book a flight from St. Louis to Pennsylvania (average of $323). Flying from St. Louis to Pennsylvania in July is currently the most expensive (average of $452). 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 August 8, 2026.
It’s optimal to fly from St. Louis to Pennsylvania in the afternoon. By choosing this option you can save up to 36% 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 August 8, 2026.
The most flights from STL to USPA are scheduled on a Monday (10 on average). You will have fewer flight options on Saturday, which is when the least amount of flights are scheduled (1 on average).
How much does it cost to fly round-trip from St. Louis to Pennsylvania?
Airfare is below average for this route at the moment.
St. Louis to Pennsylvania flights typically cost between $277 and $457 in September.The cheapest round-trip price found within the last 5 days was $147 on Frontier (Sep 7-Sep 10).
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 84 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 August 1, 2026.
Travelers seeking maximum savings on their St. Louis to Pennsylvania flight should consider departing on Thursday afternoons when fares are most often at their lowest. Tuesday evenings 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 August 8, 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.
Boarding
8.1
Entertainment
7.5
Overall
8.0
Comfort
8.0
Food
7.0
Crew
8.6
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Boarding
8.1
Entertainment
7.5
Overall
8.0
Comfort
8.0
Food
7.0
Crew
8.6
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Boarding
8.1
Entertainment
7.5
Overall
8.0
Comfort
8.0
Food
7.0
Crew
8.6
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Boarding
8.1
Entertainment
7.5
Overall
8.0
Comfort
8.0
Food
7.0
Crew
8.6
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Boarding
8.1
Entertainment
7.5
Overall
8.0
Comfort
8.0
Food
7.0
Crew
8.6
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Boarding
8.1
Entertainment
7.5
Overall
8.0
Comfort
8.0
Food
7.0
Crew
8.6
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
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 August 8, 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 August 8, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$124 | Average$236 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$168 | Average$381 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$196 | Average$355 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$231 | Average$410 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$248 | Average$390 | FlexibilityNo cancel fee | On-timeN/A |