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St. Louis

Find cheap United Airlines flights to St. Louis

RDU — STL
Aug 26 — Sep 21
Wed 8/26
Wed 9/2
1 adult, Economy
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Find United Airlines flight deals to St. Louis

Cheapest United Airlines flights from USA to St. Louis
Explore the most affordable United Airlines flight options available from USA to St. Louis. Find the lowest fares with prices last updated on July 27, 2026.

This United Airlines deal was found by Cheapflights users on 7/22. 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.
Sat 8/155:35 pm
DEN
-
STL
Nonstop2h 11m
United Airlines
Sat 8/224:40 pm
STL
-
DEN
Nonstop2h 30m
United Airlines
Deal found 7/22$187
This United Airlines deal was found by Cheapflights users on 7/23. 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 8/174:11 pm
DFW
-
STL
1 stop5h 49m
United Airlines
Tue 8/253:13 pm
STL
-
DFW
1 stop4h 44m
United Airlines
Deal found 7/23$217
This United Airlines deal was found by Cheapflights users on 7/25. 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.
Wed 8/265:35 pm
DEN
-
STL
Nonstop2h 11m
United Airlines
Fri 8/284:40 pm
STL
-
DEN
Nonstop2h 30m
United Airlines
Deal found 7/25$241

Flights to St. Louis with United Airlines at a glance

Find detailed information about United Airlines flights from USA to St. Louis. Explore the options provided by United Airlines to plan your journey from USA to St. Louis. Data last updated July 27, 2026.

Popular in

March

Cheapest in

September

Average price

$431

Round-trip from

$187

One-way from

$74

Good round-trip deal

$397 or less

Good one-way deal

$227 or less
Highest demand for flights to St. Louis with United Airlines; 11% potential price increase.
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Best time to find cheap flights to St. Louis with United Airlines; 2% potential price drop.
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Average price for flights to St. Louis with United Airlines (round-trip).
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United Airlines
  • United Airlines
  • 8/15-8/22
  • Nonstop
  • 4h 41m total
  • USA to St. Louis
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United Airlines
  • United Airlines
  • 12/5
  • 1 total stop
  • 6h 43m total
  • USA to St. Louis
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Price to beat on a round-trip flight from the United States to St. Louis with United Airlines.
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Price to beat on a one-way flight from the United States to St. Louis with United Airlines.
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Cheapflights Insights

Find cheap United Airlines flights to St. Louis

How long is the flight to St. Louis with United Airlines?

On average, United Airlines flights from the United States to St. Louis take 2 hours 3 minutes. Flights to St. Louis from other popular cities in the United States will vary in length. Below are a few examples of popular routes and their flight times.

United Airlines weekly flight availability to St. Louis

The most flights to St. Louis operated by United Airlines are scheduled on a Friday (30 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (22 on average).

When is the best time to book a flight to St. Louis with United Airlines?

The best time to book a flight to St. Louis with United Airlines is 72 days before departure. On average, fares are higher if you book 1 day before departure.

When is the cheapest time to fly to St. Louis with United Airlines?

Users looking for the cheapest United Airlines fares to St. Louis should consider flying on Saturday evenings, when prices are typically cheapest. Budget-minded travellers will want to avoid Monday at noon, when prices are usually at their highest.

FAQs about flights to St. Louis with United Airlines

  • Which airport do United Airlines flights arrive at when travelling to St. Louis?

    United Airlines flights on this route tend to land at Lambert-St Louis Airport.

  • Is United Airlines the cheapest airline for a flight to St. Louis?

    Flight prices will depend on many factors like date, time and cabin class so it is worth comparing flights before booking. Based on Cheapflights data the cheapest average return price for flights to St. Louis tends to be with Allegiant Air.

  • Are there alternative airlines other than United Airlines that fly to St. Louis?

    Southwest, American Airlines and Delta all fly to St. Louis and offer an alternative to United Airlines.

  • How much is a flight to St. Louis with United Airlines?

    The average price for a return flight with United Airlines is $432; with a one-way flight around $287.

See more FAQs

Reviews of United Airlines

See what Cheapflights users have to say about their United Airlines experience.
United Airlines
7.4
Good
10,000 reviews
Overview

Comfort

7.3

Boarding

7.7

Entertainment

7.1

Food

6.6

Crew

8.1

Popular United Airlines flights

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