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St. Louis

$150+ Cheap flights from Portland, ME to St. Louis (PWM - 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 6/10. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — STL
Apr 13 — Apr 201
Mon 4/13
Mon 4/20
1 adult, Economy
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1. Tell us where you want to go

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Cheap flight deals from Portland to St. Louis

Cheapest flights from Portland to St. Louis
Explore the most affordable flight options available from Portland to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 14, 2026.

This American Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/116:01 pm
PWM
-
STL
1 stop5h 16m
American Airlines
Tue 4/146:35 am
STL
-
PWM
1 stop7h 34m
American Airlines
Deal found 3/12$315
This Delta deal was found by Cheapflights users on 3/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/272:05 pm
PWM
-
STL
1 stop8h 24m
Delta
Tue 6/95:30 pm
STL
-
PWM
1 stop5h 23m
Delta
Deal found 3/10$319
This Delta deal was found by Cheapflights users on 3/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/114:48 pm
PWM
-
STL
1 stop4h 54m
Delta
Wed 4/156:48 am
STL
-
PWM
1 stop4h 17m
Delta
Deal found 3/9$323
This Southwest deal was found by Cheapflights users on 3/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 6/23:55 pm
PWM
-
STL
1 stop6h 10m
Southwest
Thu 6/43:45 pm
STL
-
PWM
2 stops7h 20m
Southwest
Deal found 3/11$328
This Southwest deal was found by Cheapflights users on 3/13. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/143:55 pm
PWM
-
STL
1 stop6h 10m
Southwest
Thu 4/165:00 am
STL
-
PWM
1 stop6h 10m
Southwest
Deal found 3/13$331
This American Airlines deal was found by Cheapflights users on 3/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/93:39 pm
PWM
-
STL
1 stop5h 20m
American Airlines
Tue 4/143:24 pm
STL
-
PWM
1 stop5h 49m
American Airlines
Deal found 3/11$333
This American Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/136:01 pm
PWM
-
STL
1 stop6h 55m
American Airlines
Wed 5/207:05 am
STL
-
PWM
1 stop15h 17m
American Airlines
Deal found 3/12$334
This American Airlines deal was found by Cheapflights users on 3/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/47:10 am
PWM
-
STL
1 stop6h 32m
American Airlines
Tue 4/216:29 am
STL
-
PWM
1 stop7h 08m
American Airlines
Deal found 3/12$336
This American Airlines deal was found by Cheapflights users on 3/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/153:39 pm
PWM
-
STL
1 stop5h 20m
American Airlines
Mon 4/205:21 pm
STL
-
PWM
1 stop5h 06m
American Airlines
Deal found 3/10$343
This Delta deal was found by Cheapflights users on 3/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/114:48 pm
PWM
-
STL
1 stop4h 54m
Delta
Mon 4/1310:50 am
STL
-
PWM
1 stop4h 07m
Delta
Deal found 3/9$347

Find flight deals from Portland to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Portland (PWM) to St. Louis (STL). 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 March 14, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$315
(American Airlines)

One-way from

$150
(Southwest)

Popular in

November

Cheapest in

September

Average price

$344
Provider with most accurate pricing for Portland-Lambert-St Louis flight deals.
Search Deals
Provider most trusted by Cheapflights users for Portland-Lambert-St Louis flights.
Search Deals
From Portland to Lambert-St Louis
Search Deals
One-way flight from Portland to Lambert-St Louis
Search Deals
High demand for flights, 2% potential price rise
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($13 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Portland 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 March 14, 2026.
Use the filters below to find and compare flights from Portland to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Wed 5/27

2:05 pm-9:29 pm

1 stop8h 24m

Lambert-St Louis

Tue 6/9

5:30 pm-11:53 pm

1 stop5h 23m

$319

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Thu 4/9

6:01 pm-11:46 pm

1 stop6h 45m

Lambert-St Louis

Tue 4/14

3:24 pm-10:13 pm

1 stop5h 49m

$353

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Sat 4/11

12:45 pm-8:00 pm

2 stops8h 15m

Lambert-St Louis

Tue 4/14

6:35 am-12:20 pm

1 stop4h 45m

$358

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Tue 5/5

4:50 pm-10:56 pm

1 stop7h 06m

Lambert-St Louis

Wed 5/6

7:45 am-7:04 pm

2 stops10h 19m

$384

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Sat 4/11

6:00 am-12:22 pm

1 stop7h 22m

Lambert-St Louis

Tue 4/14

7:45 am-6:37 pm

2 stops9h 52m

$385

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Sun 4/5

5:23 am-11:09 am

1 stop6h 46m

Lambert-St Louis

Fri 4/17

4:41 pm-11:23 pm

1 stop5h 42m

$417
Quickest round-trip

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Fri 5/22

4:51 pm-9:16 pm

1 stop5h 25m

Lambert-St Louis

Sun 5/24

7:22 am-2:26 pm

1 stop6h 04m

$427
Cheapest one-way

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Wed 6/10

3:45 pm-11:10 pm

2 stops8h 25m

$155

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Mon 4/6

5:40 pm-12:05 am

1 stop7h 25m

$174
Quickest one-way

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Fri 5/8

11:03 am-3:35 pm

1 stop5h 32m

$204

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/9

Showing 1-10 of 15 resultsSorted by cheapest first
1
2

Compare providers for flights from Portland to St. Louis

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 Portland to St. Louis in March.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Portland, Maine-St. Louis flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Portland, Maine-St. Louis flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Portland, Maine-St. Louis flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Portland, Maine-St. Louis 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 Portland, Maine-St. Louis 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 Portland to St. Louis

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Portland with our price prediction graph.
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 Portland to St. Louis

What is the cheapest month to book a flight from Portland, Maine to St. Louis?

Currently, October is the cheapest month in which you can book a flight from Portland, Maine to St. Louis (average of $161). Flying from Portland, Maine to St. Louis in March is currently the most expensive (average of $334). 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.

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. 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 St. Louis. Reviews last updated March 14, 2026.
Get a feel of what it's like to fly with Delta and American Airlines from Portland to St. Louis by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
7.9
Good
8,291 reviews

Overall

7.9

Boarding

8.1

Comfort

7.9

Crew

8.5

Entertainment

7.8

Food

7.2

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
Delta
7.9
Good
8,291 reviews
Delta
7.9
Good
8,291 reviews

Overall

7.9

Boarding

8.1

Comfort

7.9

Crew

8.5

Entertainment

7.8

Food

7.2

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
American Airlines
7.1
Good
11,464 reviews
Delta
7.9
Good
8,291 reviews

Overall

7.9

Boarding

8.1

Comfort

7.9

Crew

8.5

Entertainment

7.8

Food

7.2

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.

Related info for your journey

Find useful and relevant information for your journey from Portland to St. Louis. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from Portland, Maine to St. Louis?

    A quick flight from Portland, Maine to St. Louis can take about 6h 45m. Delta provides one of the quickest options available for as low as $353. Portland, Maine and St. Louis are separated by a distance of 1092 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the cheapest airlines flying from Portland, Maine to St. Louis round-trip?

    Flying on Delta is currently your cheapest option to St. Louis, with prices starting at $236. Another option worth looking into is American Airlines, starting at $296 round trip. Delta is 46% cheaper than the average price of flights available within the next 90 days to this destination.

  • What are the cheapest airlines to fly from Portland, Maine to St. Louis one-way?

    For one-way options, check prices for Delta. According to our data, you can fly for as low as $149. Users have also found prices from $163 and $198 on American Airlines and United Airlines, respectively.

  • Can I find deals for flights from Portland to St. Louis that include hotel bookings?

    Yes. In addition to deals on Portland to St. Louis flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Portland to St. Louis?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Portland to St. Louis.

  • Can I find deals for business class flights from Portland to St. Louis?

    Yes. Cheapflights offers flight deals from Portland to St. Louis by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Portland, Maine to St. Louis?

    Currently, October is the cheapest month in which you can book a flight from Portland, Maine to St. Louis (average of $161). Flying from Portland, Maine to St. Louis in March is currently the most expensive (average of $334). 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.

See more FAQs

Traveling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
Edwardsville
O'Fallon
Fenton
Swansea
Fairview Heights
Maryland Heights
Collinsville
Eureka
Wentzville
Glencoe
Chesterfield
Alton
Farmington
Festus

Browse thousands of different options on Cheapflights for your next trip

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Top 2 airlines flying from Portland to St. Louis

Discover the top 2 airlines that operate flights from Portland 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 March 14, 2026.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$236Average$386FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$296Average$472FlexibilityNo cancel feeOn-time71%

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