Portland

$181+ 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 8/28. Fares are subject to change and may not be available on all flights or dates of travel.
STL — PWM
Jul 10 — Jul 171
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Cheap flight deals from St. Louis to Portland

Cheapest flights from St. Louis to Portland
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 June 10, 2026.

This Delta deal was found by Cheapflights users on 6/9. 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.
Wed 8/123:39 pm
STL
-
PWM
1 stop6h 34m
Delta
Wed 8/196:30 am
PWM
-
STL
1 stop6h 17m
Delta
Deal found 6/9$275
This Southwest deal was found by Cheapflights users on 6/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 8/263:45 pm
STL
-
PWM
1 stop5h 20m
Southwest
Wed 9/22:50 pm
PWM
-
STL
2 stops8h 20m
Southwest
Deal found 6/10$281
This Southwest deal was found by Cheapflights users on 6/9. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/218:20 am
STL
-
PWM
1 stop5h 35m
Southwest
Tue 10/275:50 am
PWM
-
STL
2 stops8h 40m
Southwest
Deal found 6/9$282
This United Airlines deal was found by Cheapflights users on 6/9. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/188:00 am
STL
-
PWM
1 stop5h 34m
United Airlines
Mon 8/315:03 pm
PWM
-
STL
1 stop5h 57m
United Airlines
Deal found 6/9$304
This Delta deal was found by Cheapflights users on 6/9. 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.
Wed 9/25:25 pm
STL
-
PWM
1 stop5h 05m
Delta
Sun 9/66:30 am
PWM
-
STL
1 stop6h 17m
Delta
Deal found 6/9$307
This Southwest deal was found by Cheapflights users on 6/8. 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 9/17:15 am
STL
-
PWM
1 stop6h 00m
Southwest
Thu 9/103:40 pm
PWM
-
STL
2 stops7h 25m
Southwest
Deal found 6/8$309
This Southwest deal was found by Cheapflights users on 6/9. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/2011:50 am
STL
-
PWM
2 stops8h 40m
Southwest
Mon 10/266:30 am
PWM
-
STL
1 stop6h 35m
Southwest
Deal found 6/9$310
This American Airlines deal was found by Cheapflights users on 6/10. 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.
Tue 8/46:00 am
STL
-
PWM
1 stop5h 37m
American Airlines
Mon 8/106:46 pm
PWM
-
STL
1 stop5h 48m
American Airlines
Deal found 6/10$322
This Delta deal was found by Cheapflights users on 6/9. 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.
Wed 8/129:15 am
STL
-
PWM
2 stops14h 44m
Delta
Tue 8/256:05 am
PWM
-
STL
1 stop6h 41m
Delta
Deal found 6/9$325
This Delta deal was found by Cheapflights users on 6/8. 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 10/24:59 pm
STL
-
PWM
1 stop5h 26m
Delta
Wed 10/76:00 am
PWM
-
STL
1 stop7h 56m
Delta
Deal found 6/8$332

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 June 10, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$275
(Delta)

One-way from

$181
(Kiwi.com)

Popular in

January

Cheapest in

November

Average price

$452
Provider with most accurate pricing for Lambert-St Louis-Portland flight deals.
Provider most trusted by Cheapflights users for Lambert-St Louis-Portland flights.
From Lambert-St Louis to Portland
One-way flight from Lambert-St Louis to Portland
Highest demand for flights based on searches. 10% potential increase in price ($50 potential increase over avg. RT price).
Cheapest flight prices on average. 3% potential price decrease ($14 potential savings vs. average RT price).
Average for round-trip flights in June 2026

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 June 10, 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

Price

Cheapest round-trip

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Sat 8/22

6:45 am-3:00 pm

1 stop7h 15m

Portland

Tue 8/25

5:45 am-10:05 am

1 stop5h 20m

$304

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Sat 8/15

2:00 pm-9:33 pm

1 stop6h 33m

Portland

Fri 8/21

6:05 am-11:46 am

1 stop6h 41m

$361

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Sat 8/22

7:25 am-7:17 pm

2 stops10h 52m

Portland

Tue 8/25

5:03 pm-10:00 pm

1 stop5h 57m

$399
Quickest round-trip

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Sun 8/23

6:00 am-1:07 pm

1 stop6h 07m

Portland

Wed 8/26

6:30 am-11:47 am

1 stop6h 17m

$427

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Mon 7/6

2:30 pm-12:10 am

2 stops8h 40m

Portland

Mon 7/13

5:35 am-6:30 pm

2 stops13h 55m

$472

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Mon 8/31

12:59 pm-11:59 pm

2 stops10h 00m

Portland

Sat 9/5

5:15 am-12:03 pm

2 stops7h 48m

$483

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Sat 8/1

3:45 pm-11:45 pm

2 stops7h 00m

Portland

Sat 8/8

5:40 am-12:35 pm

2 stops7h 55m

$503

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Mon 6/22

5:20 pm-12:05 am

1 stop5h 45m

Portland

Thu 6/25

5:20 pm-11:10 pm

1 stop6h 50m

$507

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Wed 7/15

6:01 am-1:25 pm

1 stop6h 24m

Portland

Tue 7/21

5:15 am-12:11 pm

2 stops7h 56m

$522
Cheapest one-way

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Fri 7/10

5:20 pm-12:10 am

1 stop5h 50m

$214

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/10

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

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 June.
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 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.
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, November is the cheapest month in which you can book a flight from St. Louis to Portland, Maine (average of $326). 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?

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 June 10, 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.

Crew

8.6

Entertainment

7.5

Boarding

8.1

Overall

7.9

Food

7.0

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.

Crew

8.6

Entertainment

7.5

Boarding

8.1

Overall

7.9

Food

7.0

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.

Crew

8.6

Entertainment

7.5

Boarding

8.1

Overall

7.9

Food

7.0

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.

Crew

8.6

Entertainment

7.5

Boarding

8.1

Overall

7.9

Food

7.0

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.

Crew

8.6

Entertainment

7.5

Boarding

8.1

Overall

7.9

Food

7.0

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

La Tracimeldamarcos,Jun 2026

LAX - SLC

The second flight was not as comfortable as the first as we had to change planes to what seemed to be a slightly older aircraft. The seats weren’t as comfortable as the other plane. But it wasn’t bad.

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

    For as low as $361, Southwest can have you in Portland, Maine from St. Louis in 6h 33m. St. Louis and Portland, Maine are separated by a distance of 1092 mi. This flight may include one or multiple stops.

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

    According to our current data, Southwest ($284), American Airlines ($284), and Delta ($298) offers the cheapest pricing from St. Louis to Portland, Maine. These flights start at 34% lower than the current average price 3 months from now.

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

    $142 is the cheapest one-way deal found within the past few days, from Delta. You may also be able to find cheap deals on Southwest and American Airlines, with prices starting from $143 and $176, respectively.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from St. Louis to Portland 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 St. Louis to Portland, Maine?

    Currently, November is the cheapest month in which you can book a flight from St. Louis to Portland, Maine (average of $326). 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.

See more FAQs

Traveling to a place near Portland?

Book flights to Portland if you plan to visit one of these locations
North Conway
Brunswick
Lewiston
Conway

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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 June 10, 2026.
AirlineCheapestAverageFlexibilityOn-time
SouthwestCheapest$284Average$482FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$284Average$417FlexibilityNo cancel feeOn-time71%
DeltaCheapest$298Average$436FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$327Average$466FlexibilityNo cancel feeOn-time69%

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