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$132+ 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 1/20. Fares are subject to change and may not be available on all flights or dates of travel.
STL — PWM
Nov 27 — Dec 41
Thu 11/27
Thu 12/4
1 adult, Economy
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Cheapflights Tip: The best prices from Lambert-St Louis to Portland are usually found in January or November, booked 58 days in advance, depart on a Tuesday or Saturday and return on a Tuesday

Cheap 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 October 28, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$301
(Delta)

One-way from

$132
(Kiwi.com)

Popular in

August

Cheapest in

January

Average price

$416
Provider with most accurate pricing for Lambert-St Louis-Portland flight deals.
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Provider most trusted by Cheapflights users for Lambert-St Louis-Portland flights.
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From Lambert-St Louis to Portland
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One-way flight from Lambert-St Louis to Portland
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Highest demand for flights based on searches. 1% potential increase in price ($7 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($6 potential savings vs. average RT price).
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Average for round-trip flights in October 2025
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Find 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 October 28, 2025.

This Delta deal was found by Cheapflights users on 10/27. 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.
Fri 12/54:32 pmSTL - PWM
1 stop6h 27mDelta
Tue 12/96:08 amPWM - STL
1 stop7h 56mDelta
Deal found 10/27$301
This American Airlines deal was found by Cheapflights users on 10/28. 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 12/232:04 pmSTL - PWM
1 stop7h 47mAmerican Airlines
Thu 1/15:20 pmPWM - STL
1 stop5h 25mAmerican Airlines
Deal found 10/28$335
This American Airlines deal was found by Cheapflights users on 10/28. 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 11/209:50 amSTL - PWM
1 stop5h 50mAmerican Airlines
Sat 11/226:00 amPWM - STL
1 stop5h 14mAmerican Airlines
Deal found 10/28$382
This Southwest deal was found by Cheapflights users on 10/28. 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 11/201:15 pmSTL - PWM
2 stops8h 00mSouthwest
Sat 11/225:40 pmPWM - STL
1 stop6h 40mSouthwest
Deal found 10/28$397
This Kiwi.com deal was found by Cheapflights users on 10/27. 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.
Thu 11/132:12 pmSTL - PWM
1 stop17h 54mMultiple Airlines
Sun 11/163:15 pmPWM - STL
2 stops23h 02mMultiple Airlines
Deal found 10/27$422
This Delta deal was found by Cheapflights users on 10/28. 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.
Thu 11/206:00 amSTL - PWM
1 stop5h 30mDelta
Sun 11/2312:48 pmPWM - STL
1 stop5h 21mDelta
Deal found 10/28$427
This Delta deal was found by Cheapflights users on 10/28. 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.
Thu 11/207:05 amSTL - PWM
2 stops8h 02mDelta
Sat 11/2212:48 pmPWM - STL
2 stops10h 10mDelta
Deal found 10/28$437
This United Airlines deal was found by Cheapflights users on 10/28. 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 12/238:05 amSTL - PWM
1 stop5h 09mUnited Airlines
Thu 1/15:30 amPWM - STL
2 stops9h 56mUnited Airlines
Deal found 10/28$441
This Southwest deal was found by Cheapflights users on 10/28. 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 11/2012:45 pmSTL - PWM
2 stops8h 30mSouthwest
Sun 11/2311:50 amPWM - STL
2 stops8h 45mSouthwest
Deal found 10/28$447

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 October 28, 2025.
Use the filters below to find and compare flights from St. Louis to Portland that are best for you.

Fly from

St. Louis

Fly to

Portland

Route

Depart

Return

Price

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Fri 12/5

4:32 pm-11:59 pm

1 stop6h 27m

Portland

Tue 12/9

6:08 am-1:04 pm

1 stop7h 56m

$301

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Sat 2/28

6:45 am-11:57 am

1 stop4h 12m

Portland

Wed 3/4

6:00 am-11:55 am

1 stop6h 55m

$318

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Thu 11/20

9:50 am-4:40 pm

1 stop5h 50m

Portland

Sat 11/22

6:00 am-10:14 am

1 stop5h 14m

$382

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Thu 11/20

1:15 pm-10:15 pm

2 stops8h 00m

Portland

Sat 11/22

5:40 pm-11:20 pm

1 stop6h 40m

$397

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Thu 3/12

5:20 am-11:55 am

1 stop5h 35m

Portland

Mon 3/16

12:35 pm-5:50 pm

1 stop6h 15m

$407

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Thu 4/2

6:45 am-11:57 am

1 stop4h 12m

Portland

Sun 4/5

4:50 pm-8:39 pm

1 stop4h 49m

$407

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Thu 11/20

6:00 am-12:30 pm

1 stop5h 30m

Portland

Sun 11/23

12:48 pm-5:09 pm

1 stop5h 21m

$427

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Tue 12/23

10:48 am-5:38 pm

2 stops29h 50m

$133

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Mon 11/24

2:00 pm-10:19 pm

1 stop7h 19m

$136

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Thu 12/18

2:04 pm-10:51 pm

1 stop7h 47m

$150

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/28

Showing 1-10 of 18 results
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 October.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice 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 eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on St. Louis-Portland, Maine flight deals on Cheapflights vs. eDreams >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 eDreams the most. eDreams 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?

Use this chart to determine the optimal time to book a round-trip flight from St. Louis to Portland. Price data was last updated on October 24, 2025.

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 58 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, January is the cheapest month in which you can book a flight from St. Louis to Portland, Maine (average of $120). Flying from St. Louis to Portland, Maine in June is currently the most expensive (average of $279). 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 PWM?

Find hourly flight availability from St. Louis to Portland. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated October 28, 2025.

When flying from St. Louis to Portland, Maine, the time of day you fly usually plays a role in the price. Save by searching for a flight in the evening, which can drop the price by up to 34% versus a flight at noon.

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 October 28, 2025.
See what other customers who have flown with Southwest, Delta, and United 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.
Southwest
8.0
Very good
4,240 reviews

Food

7.0

Crew

8.6

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Southwest
8.0
Very good
4,240 reviews
Southwest
8.0
Very good
4,240 reviews

Food

7.0

Crew

8.6

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Delta
7.9
Good
7,994 reviews
Southwest
8.0
Very good
4,240 reviews

Food

7.0

Crew

8.6

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
United Airlines
7.4
Good
9,001 reviews
Southwest
8.0
Very good
4,240 reviews

Food

7.0

Crew

8.6

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
American Airlines
7.2
Good
11,032 reviews
Southwest
8.0
Very good
4,240 reviews

Food

7.0

Crew

8.6

Entertainment

7.5

Comfort

8.0

Boarding

8.1

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines

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 $301, Delta can have you in Portland, Maine from St. Louis in 6h 27m. St. Louis and Portland, Maine are separated by a distance of 1092 mi.

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

    According to our current data, United Airlines ($212), American Airlines ($284), and Delta ($298) offers the cheapest pricing from St. Louis to Portland, Maine. These flights start at 49% 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?

    $136 is the cheapest one-way deal found within the past few days, from Delta. You may also be able to find cheap deals on American Airlines and Southwest, with prices starting from $150 and $155, 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, January is the cheapest month in which you can book a flight from St. Louis to Portland, Maine (average of $120). Flying from St. Louis to Portland, Maine in June is currently the most expensive (average of $279). 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
Auburn
Conway

Browse thousands of different options on Cheapflights for your next trip

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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 October 28, 2025.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$212Average$569FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$284Average$408FlexibilityNo cancel feeOn-time71%
DeltaCheapest$298Average$391FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$308Average$489FlexibilityNo cancel feeOn-time63%

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