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St. Louis

$158+ Cheap flights from Harrisburg to St. Louis (MDT - STL)

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 10/20. Fares are subject to change and may not be available on all flights or dates of travel.
MDT — STL
Oct 11 — Oct 181
Sat 10/11
Sat 10/18
1 adult, Economy
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Cheapflights Tip: The best prices from Harrisburg to Lambert-St Louis are usually found in April or October, booked 29 days in advance, depart on a Thursday or Saturday and return on a Thursday

Cheap flight deals from Harrisburg to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Harrisburg (MDT) to St. Louis (STL). 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

$249
(American Airlines)

One-way from

$158
(Kiwi.com)

Popular in

March

Cheapest in

April

Average price

$303
From Harrisburg to Lambert-St Louis
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One-way flight from Harrisburg to Lambert-St Louis
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Highest demand for flights based on searches. 2% potential increase in price ($9 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($5 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 Harrisburg to St. Louis

Cheapest flights from Harrisburg to St. Louis
Explore the most affordable flight options available from Harrisburg to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 11, 2025.

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 11/126:48 amMDT - STL
1 stop8h 32mAmerican Airlines
Mon 11/175:56 pmSTL - MDT
1 stop4h 57mAmerican Airlines
Deal found 9/10$249
This Delta deal was found by Cheapflights users on 9/9. 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 9/246:00 amMDT - STL
1 stop7h 21mDelta
Sun 9/286:01 amSTL - MDT
1 stop3h 57mDelta
Deal found 9/9$259
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/2210:57 amMDT - STL
2 stops23h 09mFrontier
Thu 9/2510:49 amSTL - MDT
2 stops22h 23mFrontier
Deal found 9/10$276
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.
Thu 10/96:15 amMDT - STL
1 stop4h 41mAmerican Airlines
Sun 10/126:00 amSTL - MDT
1 stop4h 40mAmerican Airlines
Deal found 9/10$300
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/196:23 pmMDT - STL
1 stop6h 01mDelta
Sun 9/216:01 amSTL - MDT
1 stop3h 57mDelta
Deal found 9/10$309
This United Airlines deal was found by Cheapflights users on 9/9. 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.
Thu 10/96:30 amMDT - STL
1 stop5h 19mUnited Airlines
Sun 10/125:00 amSTL - MDT
1 stop4h 14mUnited Airlines
Deal found 9/9$319
This American Airlines deal was found by Cheapflights users on 9/9. 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 9/118:34 amMDT - STL
1 stop4h 23mAmerican Airlines
Mon 9/152:11 pmSTL - MDT
1 stop7h 31mAmerican Airlines
Deal found 9/9$324
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/1911:07 amMDT - STL
2 stops22h 59mFrontier
Sun 9/2110:39 amSTL - MDT
2 stops22h 23mFrontier
Deal found 9/10$329
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.
Fri 9/126:23 pmMDT - STL
1 stop6h 01mDelta
Sun 9/146:01 amSTL - MDT
1 stop3h 57mDelta
Deal found 9/11$339
This United Airlines deal was found by Cheapflights users on 9/9. 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.
Thu 10/26:30 amMDT - STL
1 stop6h 58mUnited Airlines
Sun 10/55:00 amSTL - MDT
1 stop4h 14mUnited Airlines
Deal found 9/9$344
This United Airlines deal was found by Cheapflights users on 9/8. 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.
Fri 10/106:30 amMDT - STL
1 stop5h 19mUnited Airlines
Fri 10/243:23 pmSTL - MDT
1 stop5h 02mUnited Airlines
Deal found 9/8$345
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.
Thu 9/1810:29 amMDT - STL
1 stop6h 17mAmerican Airlines
Sun 9/216:00 amSTL - MDT
1 stop4h 35mAmerican Airlines
Deal found 9/10$379

Cheapflights Fare Finder

 
Customize your flight search to find flights from Harrisburg to St. Louis 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 Harrisburg to St. Louis that are best for you.

Fly from

Harrisburg

Fly to

St. Louis

Route

Depart

Return

Price

HarrisburgSt. Louis

MDT - STL

MDTSTL

Harrisburg

Wed 11/12

7:04 pm-11:07 pm

1 stop5h 03m

Lambert-St Louis

Mon 11/17

5:56 pm-11:53 pm

1 stop4h 57m

$249

HarrisburgSt. Louis

MDT - STL

MDTSTL

Harrisburg

Mon 10/6

6:25 pm-11:41 pm

1 stop6h 16m

Lambert-St Louis

Sat 10/11

5:22 pm-11:00 pm

1 stop4h 38m

$249

HarrisburgSt. Louis

MDT - STL

MDTSTL

Harrisburg

Tue 10/7

6:25 pm-10:04 pm

1 stop4h 39m

Lambert-St Louis

Sat 10/11

3:59 pm-11:08 pm

1 stop6h 09m

$249

HarrisburgSt. Louis

MDT - STL

MDTSTL

Harrisburg

Fri 9/26

6:23 pm-11:24 pm

1 stop6h 01m

Lambert-St Louis

Sun 9/28

6:01 am-10:58 am

1 stop3h 57m

$259

HarrisburgSt. Louis

MDT - STL

MDTSTL

Harrisburg

Fri 9/26

6:23 pm-11:24 pm

1 stop6h 01m

Lambert-St Louis

Tue 9/30

9:19 am-5:28 pm

1 stop7h 09m

$259

HarrisburgSt. Louis

MDT - STL

MDTSTL

Harrisburg

Mon 9/22

10:57 am-9:06 am

2 stops23h 09m

Lambert-St Louis

Thu 9/25

10:49 am-10:12 am

2 stops22h 23m

$276

HarrisburgSt. Louis

MDT - STL

MDTSTL

Harrisburg

Thu 10/9

6:15 am-9:56 am

1 stop4h 41m

Lambert-St Louis

Sun 10/12

6:00 am-11:40 am

1 stop4h 40m

$300

HarrisburgSt. Louis

MDT - STL

MDTSTL

Harrisburg

Mon 10/6

10:57 am-8:37 pm

1 stop10h 40m

Lambert-St Louis

Fri 10/10

6:05 pm-8:22 pm

1 stop25h 17m

$305

HarrisburgSt. Louis

MDT - STL

MDTSTL

Harrisburg

Fri 9/19

6:23 pm-11:24 pm

1 stop6h 01m

Lambert-St Louis

Sun 9/21

6:01 am-10:58 am

1 stop3h 57m

$309

HarrisburgSt. Louis

MDT - STL

MDTSTL

Harrisburg

Fri 9/19

11:07 am-9:06 am

2 stops22h 59m

Lambert-St Louis

Sun 9/21

10:39 am-10:02 am

2 stops22h 23m

$329

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/10

Showing 1-10 of 16 results
1
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Best time to book a flight from Harrisburg to St. Louis

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Harrisburg 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 Harrisburg to St. Louis

How far ahead should I book a flight from Harrisburg to St. Louis?

Use this chart to determine the optimal time to book a round-trip flight from Harrisburg to St. Louis. Price data was last updated on August 29, 2025.

Booking 29 days in advance of your planned departure date is, on average, the best time to get cheap flights from Harrisburg to St. Louis. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from Harrisburg to St. Louis?

Currently, August is the cheapest month in which you can book a flight from Harrisburg to St. Louis (average of $311). Flying from Harrisburg to St. Louis in March is currently the most expensive (average of $356). 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 MDT to STL?

Find hourly flight availability from Harrisburg to St. Louis. 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.

Unlike in the afternoon, when flights are generally more expensive, you can save up to 17% on flights from Harrisburg to St. Louis by exploring options for tickets at noon.

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. 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 St. Louis. Reviews last updated September 11, 2025.
Peruse reviews from past customers who have flown with Delta, United Airlines, and American Airlines from Harrisburg to St. Louis to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,960 reviews

Boarding

8.2

Entertainment

7.9

Comfort

7.9

Food

7.3

Crew

8.5

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
Delta
8.0
Very good
7,960 reviews
Delta
8.0
Very good
7,960 reviews

Boarding

8.2

Entertainment

7.9

Comfort

7.9

Food

7.3

Crew

8.5

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
United Airlines
7.4
Good
8,937 reviews
Delta
8.0
Very good
7,960 reviews

Boarding

8.2

Entertainment

7.9

Comfort

7.9

Food

7.3

Crew

8.5

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,960 reviews

Boarding

8.2

Entertainment

7.9

Comfort

7.9

Food

7.3

Crew

8.5

Overall

8.0

Reviews

1 / 20
10.0
Excellent

Kim,May 2025

PIH - SLC

This trip was fine even with delay I had plenty of time to get connection flight!

Related info for your journey

Find useful and relevant information for your journey from Harrisburg to St. Louis. 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 Harrisburg to St. Louis?

    Departing from Harrisburg to St. Louis will take you 5h 03m. Harrisburg and St. Louis are separated by a distance of 731 mi. This flight may include one or multiple stops.

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

    Delta, at $238, was found to be the cheapest airline from Harrisburg to St. Louis.Alternate airlines to your destination round-trip include American Airlines and United Airlines. Delta is currently priced 28% below the average price you’ll pay for this route.

  • What are the cheapest airlines to fly from Harrisburg to St. Louis one-way?

    To fly one-way, consider booking your trip with United Airlines, which is currently one of the cheapest options available, starting at $272. American Airlines flights start at $299 while deals on Delta start at $358 one-way.

  • Can I find deals for flights from Harrisburg to St. Louis that include hotel bookings?

    Yes. In addition to deals on Harrisburg to St. Louis flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Harrisburg to St. Louis?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Harrisburg to St. Louis.

  • Can I find deals for business class flights from Harrisburg to St. Louis?

    Yes. Cheapflights offers flight deals from Harrisburg to St. Louis 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 Harrisburg to St. Louis?

    Currently, August is the cheapest month in which you can book a flight from Harrisburg to St. Louis (average of $311). Flying from Harrisburg to St. Louis in March is currently the most expensive (average of $356). 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
Edwardsville
O'Fallon
Fairview Heights
Maryland Heights
Collinsville
Eureka
Glencoe
St. Peters
Chesterfield
Alton
Farmington
Festus

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Alternative routes for Harrisburg to St. Louis

See prices for flight routes from nearby airports that may be better suited for you.
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Top 3 airlines flying from Harrisburg to St. Louis

Discover the top 3 airlines that operate flights from Harrisburg to St. Louis. 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
DeltaCheapest$238Average$323FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$248Average$359FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$248Average$342FlexibilityNo cancel feeOn-time71%

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