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St. Louis

$170+ 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 2/15. Fares are subject to change and may not be available on all flights or dates of travel.
PWM — STL
Feb 26 — Mar 51
Thu 2/26
Thu 3/5
1 adult, Economy
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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 January 27, 2026.

This American Airlines deal was found by Cheapflights users on 1/27. 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 4/155:45 pm
PWM
-
STL
1 stop7h 03m
American Airlines
Mon 4/207:05 am
STL
-
PWM
1 stop9h 10m
American Airlines
Deal found 1/27$334
This Delta deal was found by Cheapflights users on 1/26. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 3/256:03 am
PWM
-
STL
1 stop7h 16m
Delta
Mon 3/305:15 pm
STL
-
PWM
1 stop4h 57m
Delta
Deal found 1/26$335
This United Airlines deal was found by Cheapflights users on 1/26. 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.
Tue 2/104:10 pm
PWM
-
STL
1 stop7h 48m
United Airlines
Sat 2/1412:15 pm
STL
-
PWM
1 stop5h 41m
United Airlines
Deal found 1/26$339
This Delta deal was found by Cheapflights users on 1/27. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/155:21 am
PWM
-
STL
1 stop6h 13m
Delta
Mon 4/206:48 am
STL
-
PWM
2 stops8h 57m
Delta
Deal found 1/27$340
This Delta deal was found by Cheapflights users on 1/27. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 2/106:17 am
PWM
-
STL
2 stops11h 28m
Delta
Wed 2/1111:23 am
STL
-
PWM
2 stops10h 59m
Delta
Deal found 1/27$350
This American Airlines deal was found by Cheapflights users on 1/27. 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.
Fri 4/105:45 pm
PWM
-
STL
1 stop15h 38m
American Airlines
Mon 4/132:29 pm
STL
-
PWM
1 stop7h 41m
American Airlines
Deal found 1/27$352
This Southwest deal was found by Cheapflights users on 1/26. 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 2/231:00 pm
PWM
-
STL
2 stops8h 00m
Southwest
Tue 3/311:35 am
STL
-
PWM
2 stops9h 40m
Southwest
Deal found 1/26$369
This Southwest deal was found by Cheapflights users on 1/26. 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 3/2512:30 pm
PWM
-
STL
2 stops8h 30m
Southwest
Mon 3/304:45 pm
STL
-
PWM
1 stop6h 20m
Southwest
Deal found 1/26$372
This Southwest deal was found by Cheapflights users on 1/27. 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.
Mon 3/305:30 pm
PWM
-
STL
1 stop6h 35m
Southwest
Tue 3/316:10 am
STL
-
PWM
2 stops8h 45m
Southwest
Deal found 1/27$376

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 January 27, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$335
(Delta)

One-way from

$170
(American Airlines)

Popular in

November

Cheapest in

February

Average price

$487
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
Highest demand for flights based on searches. 3% potential increase in price ($13 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($15 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in January 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 January 27, 2026.
Use the filters below to find and compare flights from Portland to St. Louis that are best for you.

Fly from

Portland

Fly to

St. Louis

Route

Depart

Return

Price

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Wed 4/15

5:45 pm-11:48 pm

1 stop7h 03m

Lambert-St Louis

Mon 4/20

7:05 am-5:15 pm

1 stop9h 10m

$334

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Thu 2/26

4:50 pm-11:25 pm

1 stop7h 35m

Lambert-St Louis

Sat 2/28

5:05 am-10:55 am

1 stop4h 50m

$335

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Wed 3/25

6:03 am-12:19 pm

1 stop7h 16m

Lambert-St Louis

Mon 3/30

5:15 pm-11:12 pm

1 stop4h 57m

$335

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Mon 2/23

3:55 pm-10:40 pm

1 stop7h 45m

Lambert-St Louis

Tue 3/3

2:35 pm-10:15 pm

1 stop6h 40m

$335

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Wed 3/25

6:17 am-1:39 pm

1 stop8h 22m

Lambert-St Louis

Mon 3/30

10:33 am-5:07 pm

1 stop5h 34m

$335

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Wed 4/15

5:21 am-11:56 am

1 stop7h 35m

Lambert-St Louis

Mon 4/20

6:48 am-4:45 pm

2 stops8h 57m

$340

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Tue 2/10

4:10 pm-10:58 pm

1 stop7h 48m

Lambert-St Louis

Sat 2/14

11:25 am-8:28 pm

2 stops8h 03m

$344

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Sun 2/15

7:31 pm-11:59 pm

1 stop5h 28m

$170

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Sat 2/14

6:49 pm-10:52 pm

1 stop5h 03m

$170

PortlandSt. Louis

PWM - STL

PWMSTL

Portland

Sun 6/21

6:00 am-10:39 am

1 stop5h 39m

$204

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/25

Showing 1-10 of 16 results
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 January.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
GotogatePrice Accuracy2 starsTrust Score*3 stars
MytripPrice Accuracy2 starsTrust Score*3 stars
CheapfaremartPrice Accuracy-Trust Score*1 star

*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 April is currently the most expensive (average of $319). 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 January 27, 2026.
Get a feel of what it's like to fly with Delta, United Airlines, 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
8,118 reviews

Entertainment

7.8

Crew

8.5

Food

7.2

Overall

7.9

Comfort

7.9

Boarding

8.1

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
8,118 reviews
Delta
7.9
Good
8,118 reviews

Entertainment

7.8

Crew

8.5

Food

7.2

Overall

7.9

Comfort

7.9

Boarding

8.1

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.
United Airlines
7.4
Good
9,205 reviews
Delta
7.9
Good
8,118 reviews

Entertainment

7.8

Crew

8.5

Food

7.2

Overall

7.9

Comfort

7.9

Boarding

8.1

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
7.2
Good
11,197 reviews
Delta
7.9
Good
8,118 reviews

Entertainment

7.8

Crew

8.5

Food

7.2

Overall

7.9

Comfort

7.9

Boarding

8.1

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 7h 03m. American Airlines provides one of the quickest options available for as low as $334. 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 $158. Additional round-trip tickets that might be worth considering are offered by American Airlines and United Airlines, with the lowest prices starting at $296 and $341, respectively. Delta is 62% 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 $158 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 April is currently the most expensive (average of $319). 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
Swansea
Fairview Heights
Maryland Heights
Collinsville
Eureka
Glencoe
Chesterfield
Alton
Farmington
Festus

Browse thousands of different options on Cheapflights for your next trip

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Top 3 airlines flying from Portland to St. Louis

Discover the top 3 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 January 27, 2026.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$158Average$382FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$296Average$495FlexibilityNo cancel feeOn-time71%
United AirlinesCheapest$341Average$456FlexibilityNo cancel feeOn-time69%

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