Portland

$152+ 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
Jul 19 — Jul 261
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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 July 14, 2025.

Round-trip from

$279
(American Airlines)

One-way from

$152
(American Airlines)

Popular in

June

Cheapest in

January

Average price

$389
From Lambert-St Louis to Portland
One-way flight from Lambert-St Louis to Portland
Highest demand for flights based on searches. 5% potential increase in price ($24 potential increase over avg. RT price).
Cheapest flight prices on average. 1% potential price decrease ($6 potential savings vs. average RT price).
Average for round-trip flights in July 2025

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 July 14, 2025.

This American Airlines deal was found by Cheapflights users on 7/14. 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 10/47:23 amSTL - PWM
1 stop14h 20mAmerican Airlines
Tue 10/73:26 pmPWM - STL
1 stop9h 28mAmerican Airlines
Deal found 7/14$279
This Delta deal was found by Cheapflights users on 7/13. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/64:27 pmSTL - PWM
1 stop6h 04mDelta
Sat 11/812:30 pmPWM - STL
1 stop6h 32mDelta
Deal found 7/13$303
This Southwest deal was found by Cheapflights users on 7/14. 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 9/2510:30 amSTL - PWM
2 stops8h 30mSouthwest
Mon 9/295:50 amPWM - STL
1 stop6h 40mSouthwest
Deal found 7/14$350
This United Airlines deal was found by Cheapflights users on 7/13. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 8/45:20 pmSTL - PWM
1 stop4h 54mUnited Airlines
Fri 8/154:56 pmPWM - STL
1 stop6h 49mUnited Airlines
Deal found 7/13$386

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 July 14, 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

Sat 10/4

7:23 am-10:43 pm

1 stop14h 20m

Portland

Tue 10/7

3:26 pm-11:54 pm

1 stop9h 28m

$279

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Tue 8/5

6:00 am-1:20 pm

1 stop6h 20m

Portland

Thu 8/14

6:00 am-12:31 pm

1 stop7h 31m

$303

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Thu 9/25

10:30 am-8:00 pm

2 stops8h 30m

Portland

Mon 9/29

5:50 am-11:30 am

1 stop6h 40m

$350

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Mon 8/4

5:20 pm-11:14 pm

1 stop4h 54m

Portland

Fri 8/15

4:56 pm-10:45 pm

1 stop6h 49m

$386

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Sat 10/11

4:34 pm-10:45 pm

1 stop5h 11m

$152

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Fri 8/29

3:16 pm-12:46 pm

1 stop20h 30m

$156

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Sun 8/24

5:11 pm-12:03 am

1 stop5h 52m

$183

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Sun 8/24

2:30 pm-11:34 am

2 stops20h 04m

$187

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Fri 8/29

10:30 am-8:00 pm

2 stops8h 30m

$219

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

Sun 8/24

5:30 pm-7:29 pm

2 stops24h 59m

$246

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/12

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 July 11, 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 July 14, 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 July 14, 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.

Food

7.0

Overall

8.0

Entertainment

7.6

Boarding

8.1

Crew

8.6

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.

Food

7.0

Overall

8.0

Entertainment

7.6

Boarding

8.1

Crew

8.6

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.
8.0
Very good

Food

7.0

Overall

8.0

Entertainment

7.6

Boarding

8.1

Crew

8.6

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.

Food

7.0

Overall

8.0

Entertainment

7.6

Boarding

8.1

Crew

8.6

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.

Food

7.0

Overall

8.0

Entertainment

7.6

Boarding

8.1

Crew

8.6

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.

Food

7.0

Overall

8.0

Entertainment

7.6

Boarding

8.1

Crew

8.6

Comfort

8.0

Reviews

1 / 20
8.0
Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.

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

    According to our current data, American Airlines ($279), Delta ($303), and Southwest ($350) offers the cheapest pricing from St. Louis to Portland, Maine. These flights start at 31% 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?

    $152 is the cheapest one-way deal found within the past few days, from American Airlines. You may also be able to find cheap deals on Frontier and Delta, with prices starting from $156 and $183, 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 $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

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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 July 14, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$286Average$394FlexibilityNo cancel feeOn-time71%
DeltaCheapest$301Average$394FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$316Average$482FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$336Average$524FlexibilityNo cancel feeOn-time69%

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