$141+ Cheap flights from St. Louis to Portland, ME (STL - PWM)
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 8/27. Fares are subject to change and may not be available on all flights or dates of travel.
STL — PWM
Aug 26 — Sep 21
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 St. Louis to PortlandExplore the most affordable flight options available from St. Louis to Portland. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 27, 2026.
Explore the most affordable flight options available from St. Louis to Portland. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 27, 2026.
This American Airlines deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/196:00 am
STL
- PWM
1 stop15h 48m
American Airlines
Wed 8/266:09 pm
PWM
- STL
1 stop15h 15m
American Airlines
Deal found 7/24![American Airlines logo]()
$321
This American Airlines deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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 10/311:01 am
STL
- PWM
1 stop11h 46m
American Airlines
Sat 10/106:00 am
PWM
- STL
1 stop5h 41m
American Airlines
Deal found 7/23![American Airlines logo]()
$327
This United Airlines deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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 8/1312:59 pm
STL
- PWM
1 stop7h 24m
United Airlines
Wed 8/197:40 am
PWM
- STL
1 stop5h 22m
United Airlines
Deal found 7/23![United Airlines logo]()
$333
This Southwest deal was found by Cheapflights users on 7/26. Clicking the “Pick Dates” 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 9/23:45 pm
STL
- PWM
1 stop5h 20m
Southwest
Sat 9/57:25 am
PWM
- STL
1 stop4h 25m
Southwest
Deal found 7/26![Southwest logo]()
$334
This American Airlines deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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 9/115:13 pm
STL
- PWM
1 stop5h 46m
American Airlines
Mon 9/144:41 pm
PWM
- STL
1 stop5h 36m
American Airlines
Deal found 7/23![American Airlines logo]()
$338
This United Airlines deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” 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 8/223:32 pm
STL
- PWM
1 stop4h 51m
United Airlines
Thu 8/276:03 am
PWM
- STL
1 stop5h 09m
United Airlines
Deal found 7/24![United Airlines logo]()
$339
This United Airlines deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” 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 8/223:32 pm
STL
- PWM
1 stop4h 51m
United Airlines
Sat 8/295:15 am
PWM
- STL
2 stops7h 48m
United Airlines
Deal found 7/27![United Airlines logo]()
$344
This Southwest deal was found by Cheapflights users on 7/26. Clicking the “Pick Dates” 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 9/114:15 pm
STL
- PWM
1 stop5h 15m
Southwest
Sat 9/195:40 am
PWM
- STL
2 stops7h 55m
Southwest
Deal found 7/26![Southwest logo]()
$346
This Southwest deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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 10/312:55 pm
STL
- PWM
2 stops8h 15m
Southwest
Tue 10/135:40 am
PWM
- STL
2 stops10h 20m
Southwest
Deal found 7/23![Southwest logo]()
$349
This Southwest deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” 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 8/226:45 am
STL
- PWM
1 stop7h 15m
Southwest
Thu 8/2710:30 am
PWM
- STL
2 stops10h 30m
Southwest
Deal found 7/24![Southwest logo]()
$350
Best flights from St. Louis to PortlandDiscover carefully curated flight deals from St. Louis to Portland that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 27, 2026.
Discover carefully curated flight deals from St. Louis to Portland that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 27, 2026.
This Southwest deal was found by Cheapflights users on 7/25. Clicking the “Pick Dates” 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 8/226:45 am
STL
- PWM
1 stop7h 15m
Southwest
Sat 8/295:40 am
PWM
- STL
1 stop6h 10m
Southwest
Deal found 7/25![Southwest logo]()
$339
This Delta deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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 10/95:28 pm
STL
- PWM
1 stop5h 08m
Delta
Wed 10/1411:25 am
PWM
- STL
1 stop5h 15m
Delta
Deal found 7/23![Delta logo]()
$385
This United Airlines deal was found by Cheapflights users on 7/26. Clicking the “Pick Dates” 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 9/37:25 am
STL
- PWM
1 stop6h 09m
United Airlines
Sun 9/66:03 am
PWM
- STL
1 stop5h 09m
United Airlines
Deal found 7/26![United Airlines logo]()
$425
This Southwest deal was found by Cheapflights users on 7/25. Clicking the “Pick Dates” 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 8/152:55 pm
STL
- PWM
1 stop5h 05m
Southwest
Sat 8/225:40 am
PWM
- STL
2 stops8h 45m
Southwest
Deal found 7/25![Southwest logo]()
$344
This Southwest deal was found by Cheapflights users on 7/26. Clicking the “Pick Dates” 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 9/25:55 am
STL
- PWM
1 stop5h 30m
Southwest
Sat 9/55:40 am
PWM
- STL
2 stops9h 20m
Southwest
Deal found 7/26![Southwest logo]()
$344
This Southwest deal was found by Cheapflights users on 7/26. Clicking the “Pick Dates” 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 9/114:15 pm
STL
- PWM
1 stop5h 15m
Southwest
Sat 9/195:40 am
PWM
- STL
2 stops7h 55m
Southwest
Deal found 7/26![Southwest logo]()
$346
This United Airlines deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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 8/221:05 pm
STL
- PWM
2 stops9h 27m
United Airlines
Tue 8/259:49 am
PWM
- STL
2 stops13h 11m
United Airlines
Deal found 7/23![United Airlines logo]()
$433
This United Airlines deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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 9/128:00 am
STL
- PWM
2 stops9h 29m
United Airlines
Wed 9/166:06 am
PWM
- STL
2 stops10h 32m
United Airlines
Deal found 7/23![United Airlines logo]()
$433
This Southwest deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” 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 9/163:45 pm
STL
- PWM
1 stop5h 25m
Southwest
Mon 9/215:55 am
PWM
- STL
1 stop6h 40m
Southwest
Deal found 7/27![Southwest logo]()
$362
This United Airlines deal was found by Cheapflights users on 7/25. Clicking the “Pick Dates” 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.
Mon 8/1712:59 pm
STL
- PWM
2 stops10h 00m
United Airlines
Mon 8/246:03 am
PWM
- STL
1 stop6h 59m
United Airlines
Deal found 7/25![United Airlines logo]()
$434
This Southwest deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” 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 10/39:25 am
STL
- PWM
1 stop5h 30m
Southwest
Sat 10/105:35 am
PWM
- STL
2 stops8h 25m
Southwest
Deal found 7/24![Southwest logo]()
$422
Last-minute flights from St. Louis to PortlandDiscover last-minute flight deals from St. Louis to Portland. Data last updated July 27, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to Portland. Data last updated July 27, 2026 and is based on user searches.
This United Airlines deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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 8/1312:59 pm
STL
- PWM
1 stop7h 24m
United Airlines
Wed 8/197:40 am
PWM
- STL
1 stop5h 22m
United Airlines
Deal found 7/23![United Airlines logo]()
$333
This American Airlines deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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 8/136:00 am
STL
- PWM
1 stop5h 40m
American Airlines
Wed 8/1912:09 pm
PWM
- STL
1 stop13h 05m
American Airlines
Deal found 7/23![American Airlines logo]()
$378
This Southwest deal was found by Cheapflights users on 7/26. Clicking the “Pick Dates” 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 8/172:20 pm
STL
- PWM
2 stops7h 05m
Southwest
Sat 8/225:40 am
PWM
- STL
2 stops8h 45m
Southwest
Deal found 7/26![Southwest logo]()
$379
This American Airlines deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/196:00 am
STL
- PWM
1 stop15h 48m
American Airlines
Wed 8/266:09 pm
PWM
- STL
1 stop15h 15m
American Airlines
Deal found 7/24![American Airlines logo]()
$321
This American Airlines deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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 8/209:32 am
STL
- PWM
1 stop12h 16m
American Airlines
Thu 8/276:09 pm
PWM
- STL
1 stop7h 05m
American Airlines
Deal found 7/23![American Airlines logo]()
$349
This American Airlines deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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 8/221:25 pm
STL
- PWM
1 stop8h 23m
American Airlines
Tue 8/252:42 pm
PWM
- STL
1 stop7h 02m
American Airlines
Deal found 7/23![American Airlines logo]()
$327
This United Airlines deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” 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 8/223:32 pm
STL
- PWM
1 stop4h 51m
United Airlines
Thu 8/276:03 am
PWM
- STL
1 stop5h 09m
United Airlines
Deal found 7/24![United Airlines logo]()
$339
This United Airlines deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” 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 8/223:32 pm
STL
- PWM
1 stop4h 51m
United Airlines
Sat 8/295:15 am
PWM
- STL
2 stops7h 48m
United Airlines
Deal found 7/27![United Airlines logo]()
$344
This Southwest deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” 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 8/226:45 am
STL
- PWM
1 stop7h 15m
Southwest
Thu 8/2710:30 am
PWM
- STL
2 stops10h 30m
Southwest
Deal found 7/24![Southwest logo]()
$350
This American Airlines deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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.
Sun 8/239:21 am
STL
- PWM
1 stop5h 19m
American Airlines
Sat 8/296:46 pm
PWM
- STL
1 stop5h 48m
American Airlines
Deal found 7/23![American Airlines logo]()
$385
This Southwest deal was found by Cheapflights users on 7/23. Clicking the “Pick Dates” 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.
Sun 8/233:30 pm
STL
- PWM
1 stop5h 00m
Southwest
Sat 8/295:40 am
PWM
- STL
2 stops7h 55m
Southwest
Deal found 7/23![Southwest logo]()
$390
This American Airlines deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/266:00 am
STL
- PWM
1 stop5h 40m
American Airlines
Sun 8/306:46 pm
PWM
- STL
1 stop5h 48m
American Airlines
Deal found 7/27![American Airlines logo]()
$388
One-way flights from St. Louis to PortlandSearch for one-way flight options from St. Louis to Portland. Find affordable one-way fares based on user searches. Data last updated July 27, 2026.
Search for one-way flight options from St. Louis to Portland. Find affordable one-way fares based on user searches. Data last updated July 27, 2026.
This Kiwi.com deal was found by Cheapflights users on 7/26. Clicking the “Pick Dates” 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
STL
- PWM
2 stops27h 21m
Multiple Airlines
Deal found 7/26![Multiple Airlines logo]()
$141
This Kiwi.com deal was found by Cheapflights users on 7/27. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/252:29 pm
STL
- PWM
2 stops26h 22m
Multiple Airlines
Deal found 7/27![Multiple Airlines logo]()
$152
This American Airlines deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” 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 8/157:27 am
STL
- PWM
1 stop6h 40m
American Airlines
Deal found 7/24![American Airlines logo]()
$170
This Kiwi.com deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” 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
STL
- PWM
2 stops20h 59m
Multiple Airlines
Deal found 7/24![Multiple Airlines logo]()
$175
This American Airlines deal was found by Cheapflights users on 7/26. Clicking the “Pick Dates” 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 10/1511:31 am
STL
- PWM
1 stop11h 09m
American Airlines
Deal found 7/26![American Airlines logo]()
$176
This Kiwi.com deal was found by Cheapflights users on 7/25. Clicking the “Pick Dates” 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 8/216:17 pm
STL
- PWM
3 stops22h 41m
Multiple Airlines
Deal found 7/25![Multiple Airlines logo]()
$189
This Southwest deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/712:15 pm
STL
- PWM
2 stops7h 15m
Southwest
Deal found 7/24![Southwest logo]()
$205
This American Airlines deal was found by Cheapflights users on 7/25. Clicking the “Pick Dates” 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 8/214:54 pm
STL
- PWM
1 stop4h 54m
American Airlines
Deal found 7/25![American Airlines logo]()
$206
This Kiwi.com deal was found by Cheapflights users on 7/24. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/154:57 pm
STL
- PWM
3 stops28h 42m
Multiple Airlines
Deal found 7/24![Multiple Airlines logo]()
$216
Find flight deals from St. Louis to Portland
Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Portland (PWM). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated July 27, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $321 (American Airlines) |
One-way from | $141 (Kiwi.com) |
Popular in | January |
Cheapest in | March |
Average price | $516 |
Cheapflights Fare Finder
Customize your flight search to find flights from St. Louis to Portland 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 July 27, 2026.
Use the filters below to find and compare flights from St. Louis to Portland that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
St. LouisPortland
STL - PWM
STLPWM
Lambert-St Louis
Sat 8/22
6:45 am-3:00 pm
1 stop7h 15m
Portland
Sat 8/29
5:40 am-10:50 am
1 stop6h 10m
$339
St. LouisPortland
STL - PWM
STLPWM
Lambert-St Louis
Sat 8/15
2:55 pm-9:00 pm
1 stop5h 05m
Portland
Sat 8/22
5:40 am-1:25 pm
2 stops8h 45m
$344
St. LouisPortland
STL - PWM
STLPWM
Lambert-St Louis
Wed 9/2
5:55 am-12:25 pm
1 stop5h 30m
Portland
Sat 9/5
5:40 am-2:00 pm
2 stops9h 20m
$344
St. LouisPortland
STL - PWM
STLPWM
Lambert-St Louis
Fri 9/11
4:15 pm-10:30 pm
1 stop5h 15m
Portland
Sat 9/19
5:40 am-12:35 pm
2 stops7h 55m
$346
St. LouisPortland
STL - PWM
STLPWM
Lambert-St Louis
Wed 9/16
3:45 pm-10:10 pm
1 stop5h 25m
Portland
Mon 9/21
5:55 am-11:35 am
1 stop6h 40m
$362
Quickest round-trip
St. LouisPortland
STL - PWM
STLPWM
Lambert-St Louis
Fri 10/9
5:28 pm-11:36 pm
1 stop5h 08m
Portland
Wed 10/14
11:25 am-3:40 pm
1 stop5h 15m
$385
St. LouisPortland
STL - PWM
STLPWM
Lambert-St Louis
Sat 10/3
9:25 am-3:55 pm
1 stop5h 30m
Portland
Sat 10/10
5:35 am-1:00 pm
2 stops8h 25m
$422
St. LouisPortland
STL - PWM
STLPWM
Lambert-St Louis
Thu 9/3
7:25 am-2:34 pm
1 stop6h 09m
Portland
Sun 9/6
6:03 am-10:12 am
1 stop5h 09m
$425
St. LouisPortland
STL - PWM
STLPWM
Lambert-St Louis
Sat 8/22
1:05 pm-11:32 pm
2 stops9h 27m
Portland
Tue 8/25
9:49 am-10:00 pm
2 stops13h 11m
$433
St. LouisPortland
STL - PWM
STLPWM
Lambert-St Louis
Sat 9/12
8:00 am-6:29 pm
2 stops9h 29m
Portland
Wed 9/16
6:06 am-3:38 pm
2 stops10h 32m
$433
Showing 1-10 of 20 resultsSorted by cheapest first
Compare providers for flights from St. Louis to Portland
Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from St. Louis to Portland in July.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on St. Louis-Portland, Maine flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-Portland, Maine flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-Portland, Maine flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on St. Louis-Portland, Maine flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for St. Louis-Portland, Maine flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.
Best time to book a flight from St. Louis to Portland
Have a flexible travel schedule? Discover the best time to fly to Portland from St. Louis with our price prediction graph.
STL-PWM
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 Portland
How far ahead should I book a flight from St. Louis to Portland, Maine?
The price you pay for your flight from St. Louis to Portland, Maine may vary depending on when you book. For the best chance of a lower fare, look to book 45 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.
What is the cheapest month to book a flight from St. Louis to Portland, Maine?
Currently, March is the cheapest month in which you can book a flight from St. Louis to Portland, Maine (average of $349). Flying from St. Louis to Portland, Maine in January is currently the most expensive (average of $574). 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.
How much does it cost to fly round-trip from St. Louis to Portland, Maine?
Airfare is below average for this route at the moment.
St. Louis to Portland, Maine flights typically cost between $379 and $462 in August.The cheapest round-trip price found within the last 5 days was $321 on American Airlines (Aug 19-Aug 26).
Reviews of airlines servicing Portland
Get insights into the airlines that provide service to Portland. 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 Portland. Reviews last updated July 27, 2026.
See what other customers who have flown with Southwest,Delta, andUnited Airlines from St. Louis to Portland have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Entertainment
7.5
Overall
8.0
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Entertainment
7.5
Overall
8.0
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Entertainment
7.5
Overall
8.0
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Entertainment
7.5
Overall
8.0
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Boarding
8.1
Crew
8.6
Food
7.0
Comfort
8.0
Entertainment
7.5
Overall
8.0
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 Portland. 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 Portland?
Book flights to Portland if you plan to visit one of these locationsNorth Conway
Lewiston
Brunswick
Conway
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St. Louis and Portland flights
Browse other St. Louis and Portland flight options. Last updated on July 27, 2026.
Other flights from St. Louis
Browse through other flights departing from St. Louis. Flights are based on user searches made on Cheapflights and were last updated on July 27, 2026.
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Explore flights to Portland departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on July 27, 2026.
Top 4 airlines flying from St. Louis to Portland
Discover the top 4 airlines that operate flights from St. Louis to Portland. 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 July 27, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$290 | Average$420 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$298 | Average$419 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$327 | Average$465 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$358 | Average$492 | FlexibilityNo cancel fee | On-time63% |