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Cheap flights from Portland, Maine to St. Louis from $75

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Portland, Maine to St. Louis departing on 5/16. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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Find the cheapest flights from Portland, Maine to St. Louis

Cheap round-trip flights

These are some of the best round-trip flight deals from Portland, Maine to St. Louis that have been recently found on momondo from popular airlines, departing in the coming months.
10:08 am - 11:49 pmPWM-STL
14h 41m1 stop
5:24 pm - 9:08 amSTL-PWM
14h 44m1 stop
$140Frontier
Find Deal
Thu, Mar 6 - Wed, Mar 19
7:20 am - 2:45 pmPWM-STL
8h 25m1 stop
12:03 pm - 9:05 pmSTL-PWM
8h 02m1 stop
$293American Airlines
Find Deal
Wed, Apr 9 - Mon, Apr 14
5:55 am - 12:19 pmPWM-STL
7h 24m1 stop
4:37 pm - 11:55 pmSTL-PWM
6h 18m1 stop
$317American Airlines
Find Deal
Sat, May 10 - Tue, May 13
12:15 pm - 8:47 pmPWM-STL
9h 32m1 stop
5:00 am - 11:37 amSTL-PWM
5h 37m1 stop
$330American Airlines
Find Deal
Tue, Apr 29 - Fri, May 9
12:30 pm - 7:55 pmPWM-STL
8h 25m2 stops
5:45 am - 11:05 amSTL-PWM
4h 20m1 stop
$357Southwest
Find Deal
Tue, Apr 29 - Fri, May 9
6:15 am - 11:56 amPWM-STL
6h 41m1 stop
6:50 am - 4:28 pmSTL-PWM
8h 38m2 stops
$383Delta
Find Deal
Wed, Apr 9 - Mon, Apr 14
12:30 pm - 6:01 pmPWM-STL
6h 31m1 stop
6:45 am - 5:00 pmSTL-PWM
9h 15m2 stops
$387Delta
Find Deal
Wed, May 21 - Wed, May 28
6:05 am - 12:19 pmPWM-STL
7h 14m1 stop
1:10 pm - 11:59 pmSTL-PWM
9h 49m2 stops
$403United Airlines
Find Deal
Sat, May 10 - Tue, May 13
3:40 pm - 8:45 pmPWM-STL
6h 05m1 stop
5:25 am - 12:35 pmSTL-PWM
6h 10m1 stop
$407Southwest
Find Deal
Thu, Jun 26 - Mon, Jun 30
6:00 am - 3:47 pmPWM-STL
10h 47m2 stops
6:30 am - 5:43 pmSTL-PWM
10h 13m2 stops
$442United Airlines
Find Deal
Wed, May 21 - Wed, May 28

American Airlines flights from Portland, Maine to St. Louis

Our best American Airlines deals on Portland, Maine to St. Louis flight tickets
American Airlines
Apr 9
PWM7:20 amPortland
8h 25m
1 stop
STL2:45 pmLambert-St Louis
Apr 14
STL12:03 pmLambert-St Louis
8h 02m
1 stop
PWM9:05 pmPortland
American Airlines
May 10
PWM5:55 amPortland
7h 24m
1 stop
STL12:19 pmLambert-St Louis
May 13
STL4:37 pmLambert-St Louis
6h 18m
1 stop
PWM11:55 pmPortland
American Airlines
Apr 29
PWM12:15 pmPortland
9h 32m
1 stop
STL8:47 pmLambert-St Louis
May 9
STL5:00 amLambert-St Louis
5h 37m
1 stop
PWM11:37 amPortland

Southwest flights from Portland, Maine to St. Louis

Our best Southwest deals on Portland, Maine to St. Louis flight tickets
Southwest
Apr 29
PWM12:30 pmPortland
8h 25m
2 stops
STL7:55 pmLambert-St Louis
May 9
STL5:45 amLambert-St Louis
4h 20m
1 stop
PWM11:05 amPortland
Southwest
Jun 26
PWM3:40 pmPortland
6h 05m
1 stop
STL8:45 pmLambert-St Louis
Jun 30
STL5:25 amLambert-St Louis
6h 10m
1 stop
PWM12:35 pmPortland
Southwest
Jun 26
PWM3:40 pmPortland
9h 05m
2 stops
STL11:45 pmLambert-St Louis
Jun 30
STL5:25 amLambert-St Louis
6h 10m
1 stop
PWM12:35 pmPortland

See travel insights to St. Louis from

How to get the cheapest flight ticket from Portland, Maine to St. Louis

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest month to fly to St. Louis?

In general, February is the cheapest month to fly from Portland, Maine to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $250. The month of January is another great option to travel to St. Louis, with average flight prices from Portland, Maine averaging around $371.

What is the cheapest day to depart on your flight to St. Louis?

The cheapest day to depart on your flight to St. Louis is on a Tuesday when prices can be found for as low as $443. This is often the case because there is less demand to fly during this day of the week. If your travel schedule is flexible, try to avoid departing on a Monday because tickets tend to average around $638. These prices are subject to change though, so be sure to set up a Price Alert for flights to St. Louis.

What is the cheapest time of day to depart on your flight to St. Louis?

Flying to St. Louis from Portland, Maine in the afternoon is the least expensive time of day to depart. momondo users have found prices as low as $441 when looking at flights departing in the afternoon. At noon is when there is more demand to fly to St. Louis, so prices are often more expensive at around $609 per ticket.

How far in advance should I book a flight to St. Louis?

You are more likely to see cheaper flights to St. Louis from Portland, Maine when booking 25 weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around $450 when searching 25 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to St. Louis from Portland, Maine for as low as $249 on momondo.

How have Portland, Maine to St. Louis flight prices changed over time?

As of February 2025, prices for Portland, Maine to St. Louis flights are approximately 147% more expensive when compared to flights at the same time last year.

When to book flights from Portland, Maine to St. Louis

Are you open to changing your travel dates? Check out the ideal times to fly from Portland, Maine to St. Louis according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap Portland, Maine to St. Louis (PWM to STL) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Portland, Maine to St. Louis

Best Price Found

$75

Fastest flight time

5h 26m

Direct flights

None

Airports in St. Louis

1 airport
The best one-way flight to St. Louis from Portland, Maine in the past 72 hours is $75. The best round-trip flight deal from Portland, Maine to St. Louis found on momondo in the last 72 hours is $140.
The fastest flight from Portland, Maine to St. Louis takes 5h 26m
There are no direct flights from Portland, Maine to St. Louis. Popular non-direct route for this connection is Portland Airport - Lambert-St Louis Airport.
There is 1 airport near St. Louis: Lambert-St Louis (STL)

  • How far is Portland to Lambert-St Louis by plane?

    The distance between Portland and Lambert-St Louis is about 1090.4 mi. 5h 26m is a normal flight duration for this route.

  • When did momondo last update prices for flights from Portland Airport to Lambert-St Louis Airport?

    Prices for flights from Portland Airport to Lambert-St Louis Airport refresh daily.

  • How many operators does momondo search for flights from Portland Airport to Lambert-St Louis Airport?

  • How old do you have to be to fly from Portland Airport to Lambert-St Louis Airport?

    Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Portland Airport to Lambert-St Louis Airport.

  • What documentation or ID do you need to fly to Lambert-St Louis Airport?

    The travel and health documents you'll need for your trip to Lambert-St Louis Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Lambert-St Louis Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

  • What is the most popular airline from Portland, Maine to St. Louis?


Best airlines flying from Portland, Maine to St. Louis

Compare and see reviews for airlines that fly from Portland, Maine to St. Louis with momondo
Airline
Rating
Free Cancellation
Price
American AirlinesPriceFrom $314Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights
United AirlinesPriceFrom $341Free CancellationRating
7.4
8,765 reviews
Search United Airlines flights
SouthwestPriceFrom $351Free CancellationRating
8.1
4,411 reviews
Search Southwest flights
DeltaPriceFrom $361Free CancellationRating
8.0
8,219 reviews
Search Delta flights
  • Southwest Flights From Portland, Maine to St. Louis

    Southwest is one of the most popular airlines flying from Portland, Maine to St. Louis, operating 2 flights/week on average for this route. A good Southwest flight deal for Portland, Maine to St. Louis starts from $351 round-trip, up to an average price of $416. Our users have rated Southwest at 8.1/10.


Traveling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
St. Charles
Chesterfield
Collinsville
Florissant
Maryland Heights
Hermann
Fairview Heights
Fenton
O'Fallon
Farmington
Alton
St. Peters
Wentzville
Eureka
Festus
Glencoe
Clayton
Edwardsville
Litchfield
Grafton

Why use momondo?

Why should I use momondo to find a flight deal from Portland to St. Louis?

Finding the right flight to St. Louis from Portland is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to St. Louis quick and easy, saving you time and money.

Can I find flights from Portland to St. Louis with flexible booking policies on momondo?

Flights from Portland to St. Louis with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.

How can momondo help me find flights from Portland to St. Louis?

momondo helps you find the best flight between Portland and St. Louis by providing filters to narrow your choice of flights to those matching your criteria. You can select flights based on numerous factors such as price, departure and landing times, airport and airline.

I’m not ready to book a flight from Portland to St. Louis right now. Can momondo alert me if prices change?

If you are simply researching potential flights to St. Louis, momondo offers a useful price alert feature which will track prices for flights to St. Louis from Portland and alert you when they change.


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