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$159+ 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 6/10. Fares are subject to change and may not be available on all flights or dates of travel.
STL — PWM
may. 17 — may. 241
sáb. 5/17
sáb. 5/24
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 74 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 mayo 12, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

Expedia
3 stars

Round-trip from

$310
(Booking.com)

One-way from

$159
(American Airlines)

Popular in

May

Cheapest in

November

Average price

$467
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. 4% potential increase in price ($21 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 May 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 mayo 12, 2025.

This FlightHub deal was found by Cheapflights users on 5/12. 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 FlightHub is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 5/165:55 pmSTL - PWM
1 stop23h 31mFrontier
lun. 5/199:30 pmPWM - STL
1 stop27h 14mFrontier
Deal found 5/12$260
This American Airlines deal was found by Cheapflights users on 5/11. 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.
mar. 6/104:58 pmSTL - PWM
1 stop5h 05mAmerican Airlines
mar. 6/175:08 amPWM - STL
1 stop5h 18mAmerican Airlines
Deal found 5/11$317
This Delta deal was found by Cheapflights users on 5/11. 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.
mar. 6/103:42 pmSTL - PWM
1 stop7h 44mDelta
mar. 6/176:03 amPWM - STL
2 stops9h 34mDelta
Deal found 5/11$322
This United Airlines deal was found by Cheapflights users on 5/12. 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.
mar. 7/223:20 pmSTL - PWM
1 stop5h 41mUnited Airlines
sáb. 7/266:00 amPWM - STL
1 stop5h 40mUnited Airlines
Deal found 5/12$336
This Southwest deal was found by Cheapflights users on 5/11. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 9/116:30 amSTL - PWM
1 stop5h 45mSouthwest
jue. 9/183:30 pmPWM - STL
1 stop8h 05mSouthwest
Deal found 5/11$365
This Mytrip deal was found by Cheapflights users on 5/11. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 6/69:50 amSTL - PWM
3 stops25h 03mMultiple Airlines
sáb. 6/1412:58 pmPWM - STL
2 stops29h 06mMultiple Airlines
Deal found 5/11$520

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 mayo 12, 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

vie. 6/6

5:35 pm-6:02 pm

1 stop23h 27m

Portland

sáb. 6/14

7:25 pm-11:53 pm

1 stop29h 28m

$310

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

mar. 6/10

4:58 pm-11:03 pm

1 stop5h 05m

Portland

mar. 6/17

5:08 am-9:26 am

1 stop5h 18m

$317

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

mar. 6/10

3:42 pm-12:26 am

1 stop7h 44m

Portland

mar. 6/17

6:03 am-2:37 pm

2 stops9h 34m

$322

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

mar. 7/22

3:20 pm-10:01 pm

1 stop5h 41m

Portland

sáb. 7/26

6:00 am-10:40 am

1 stop5h 40m

$336

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

jue. 9/11

6:30 am-1:15 pm

1 stop5h 45m

Portland

jue. 9/18

3:30 pm-10:35 pm

1 stop8h 05m

$365

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

vie. 6/6

9:50 am-11:53 am

3 stops25h 03m

Portland

sáb. 6/14

12:58 pm-5:04 pm

2 stops29h 06m

$520

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

mar. 6/10

4:41 pm-10:44 pm

1 stop5h 03m

$159

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

mar. 6/10

10:48 am-11:30 pm

2 stops11h 42m

$164

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

dom. 6/8

6:35 am-3:25 pm

2 stops7h 50m

$259

St. LouisPortland

STL - PWM

STLPWM

Lambert-St Louis

jue. 10/9

12:28 pm-11:01 pm

2 stops9h 33m

$274

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/11

Showing 1-10 of 11 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 May.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*2 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 Expedia the most. Expedia 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 May 9, 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 21 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 mayo 12, 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.

Rainfall in Portland by month

Plan your trip to Portland by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Portland, Maine ranges from 2.9 - 4.5 inches per month. November is typically the wettest month, when rainfall can reach 4.5 in. August is typically the driest time to visit Portland, Maine when rainfall is around 2.9 in.

Temperature in Portland by month

Plan your trip to Portland by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Portland, Maine, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 68.0 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 23.0 F).

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 mayo 12, 2025.
Read reviews from past customers who have flown Southwest, Delta and United Airlines from St. Louis to Portland. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,290 reviews

Overall

8.0

Crew

8.6

Entertainment

7.6

Food

7.1

Comfort

8.0

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Gina,Apr 2025

LAS - DEN

Good, the crew was friendly and helpful. The pilot had great skills in keeping the plane stable through rough turbulence. Smooth landing, too! Thank you!
Southwest
8.0
Very good
4,290 reviews
Southwest
8.0
Very good
4,290 reviews

Overall

8.0

Crew

8.6

Entertainment

7.6

Food

7.1

Comfort

8.0

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Gina,Apr 2025

LAS - DEN

Good, the crew was friendly and helpful. The pilot had great skills in keeping the plane stable through rough turbulence. Smooth landing, too! Thank you!
Delta
8.0
Very good
7,950 reviews
Southwest
8.0
Very good
4,290 reviews

Overall

8.0

Crew

8.6

Entertainment

7.6

Food

7.1

Comfort

8.0

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Gina,Apr 2025

LAS - DEN

Good, the crew was friendly and helpful. The pilot had great skills in keeping the plane stable through rough turbulence. Smooth landing, too! Thank you!
United Airlines
7.4
Good
8,724 reviews
Southwest
8.0
Very good
4,290 reviews

Overall

8.0

Crew

8.6

Entertainment

7.6

Food

7.1

Comfort

8.0

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Gina,Apr 2025

LAS - DEN

Good, the crew was friendly and helpful. The pilot had great skills in keeping the plane stable through rough turbulence. Smooth landing, too! Thank you!
American Airlines
7.2
Good
10,000 reviews
Southwest
8.0
Very good
4,290 reviews

Overall

8.0

Crew

8.6

Entertainment

7.6

Food

7.1

Comfort

8.0

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Gina,Apr 2025

LAS - DEN

Good, the crew was friendly and helpful. The pilot had great skills in keeping the plane stable through rough turbulence. Smooth landing, too! Thank you!
Frontier
6.0
Okay
3,288 reviews
Southwest
8.0
Very good
4,290 reviews

Overall

8.0

Crew

8.6

Entertainment

7.6

Food

7.1

Comfort

8.0

Boarding

8.2

Reviews

1 / 20
10.0
Excellent

Gina,Apr 2025

LAS - DEN

Good, the crew was friendly and helpful. The pilot had great skills in keeping the plane stable through rough turbulence. Smooth landing, too! Thank you!

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, Frontier ($310), American Airlines ($317), and Delta ($322) offers the cheapest pricing from St. Louis to Portland, Maine. These flights start at 23% 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?

    $159 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 Delta and Southwest, with prices starting from $164 and $259, 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 St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
North Conway
Bath
Brunswick
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 mayo 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$286Average$389FlexibilityNo cancel feeOn-time71%
DeltaCheapest$311Average$388FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$316Average$406FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$377Average$506FlexibilityNo cancel feeOn-time69%

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