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$115+ 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 10/11. Fares are subject to change and may not be available on all flights or dates of travel.
STL — PWM
Oct 11 — Oct 181
Sat 10/11
Sat 10/18
1 adult, Economy
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Cheapflights Tip: The best prices from Lambert-St Louis to Portland are usually found in November or January, 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 September 11, 2025.

Round-trip from

$214
(Southwest)

One-way from

$115
(American Airlines)

Popular in

August

Cheapest in

November

Average price

$386
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. 0% potential increase in price ($3 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 September 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 September 11, 2025.

This Southwest deal was found by Cheapflights users on 9/10. 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.
Tue 11/46:05 amSTL - PWM
1 stop5h 05mSouthwest
Tue 11/115:30 amPWM - STL
2 stops8h 05mSouthwest
Deal found 9/10$214
This American Airlines deal was found by Cheapflights users on 9/10. 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 11/46:00 amSTL - PWM
1 stop10h 05mAmerican Airlines
Tue 11/116:00 amPWM - STL
1 stop5h 13mAmerican Airlines
Deal found 9/10$226
This American Airlines deal was found by Cheapflights users on 9/10. 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 10/86:08 pmSTL - PWM
1 stop4h 43mAmerican Airlines
Wed 10/156:00 amPWM - STL
1 stop4h 56mAmerican Airlines
Deal found 9/10$229
This Delta deal was found by Cheapflights users on 9/11. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/15:11 pmSTL - PWM
1 stop6h 00mDelta
Wed 10/86:00 amPWM - STL
1 stop5h 26mDelta
Deal found 9/11$237
This American Airlines deal was found by Cheapflights users on 9/10. 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 9/306:00 amSTL - PWM
1 stop4h 44mAmerican Airlines
Tue 9/305:20 pmPWM - STL
1 stop4h 50mAmerican Airlines
Deal found 9/10$246
This Delta deal was found by Cheapflights users on 9/11. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/66:00 amSTL - PWM
1 stop5h 22mDelta
Sat 11/812:45 pmPWM - STL
1 stop4h 47mDelta
Deal found 9/11$247
This American Airlines deal was found by Cheapflights users on 9/11. 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.
Tue 10/216:00 amSTL - PWM
1 stop7h 56mAmerican Airlines
Mon 10/276:00 amPWM - STL
1 stop4h 56mAmerican Airlines
Deal found 9/11$297

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 September 11, 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

Tue 11/4

6:05 am-12:10 pm

1 stop5h 05m

Portland

Tue 11/11

5:30 am-12:35 pm

2 stops8h 05m

$214

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Wed 10/1

5:11 pm-12:11 am

1 stop6h 00m

Portland

Wed 10/8

6:00 am-10:26 am

1 stop5h 26m

$237

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Tue 9/30

6:00 am-11:44 am

1 stop4h 44m

Portland

Tue 9/30

5:20 pm-9:10 pm

1 stop4h 50m

$246

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Thu 11/6

6:00 am-12:22 pm

1 stop5h 22m

Portland

Sat 11/8

12:45 pm-4:32 pm

1 stop4h 47m

$247

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Tue 10/21

7:16 am-10:45 pm

1 stop14h 29m

Portland

Mon 10/27

5:59 pm-11:58 pm

1 stop6h 59m

$250

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Sat 10/11

4:25 pm-11:02 pm

1 stop5h 37m

$115

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Sat 10/11

1:30 pm-10:19 pm

1 stop7h 49m

$119

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Thu 10/2

10:35 am-5:25 pm

2 stops29h 50m

$155

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Sat 10/11

11:10 am-11:20 pm

2 stops11h 10m

$160

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Wed 10/1

6:00 am-12:29 pm

1 stop5h 29m

$169

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/9

Showing 1-10 of 14 results
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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 August 29, 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 $296). Flying from St. Louis to Portland, Maine in July is currently the most expensive (average of $394). 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 September 11, 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 35% 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 September 11, 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
4,248 reviews

Food

7.0

Boarding

8.1

Overall

8.0

Entertainment

7.5

Crew

8.6

Comfort

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
4,248 reviews
Southwest
8.0
Very good
4,248 reviews

Food

7.0

Boarding

8.1

Overall

8.0

Entertainment

7.5

Crew

8.6

Comfort

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
8.0
Very good
7,960 reviews
Southwest
8.0
Very good
4,248 reviews

Food

7.0

Boarding

8.1

Overall

8.0

Entertainment

7.5

Crew

8.6

Comfort

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
8,937 reviews
Southwest
8.0
Very good
4,248 reviews

Food

7.0

Boarding

8.1

Overall

8.0

Entertainment

7.5

Crew

8.6

Comfort

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
10,000 reviews
Southwest
8.0
Very good
4,248 reviews

Food

7.0

Boarding

8.1

Overall

8.0

Entertainment

7.5

Crew

8.6

Comfort

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 $246, Southwest can have you in Portland, Maine from St. Louis in 4h 44m. 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, American Airlines ($284), Delta ($300), and Southwest ($308) offers the cheapest pricing from St. Louis to Portland, Maine. These flights start at 32% lower than the current average price 3 months from now.

  • 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 $296). Flying from St. Louis to Portland, Maine in July is currently the most expensive (average of $394). 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
Brunswick
North Conway
Auburn
Conway
Lewiston

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 September 11, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$284Average$407FlexibilityNo cancel feeOn-time71%
DeltaCheapest$300Average$393FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$308Average$462FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$336Average$506FlexibilityNo cancel feeOn-time69%

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