Cheap flights from District of Columbia to St. Louis from $126

In general, October is the cheapest month to fly from District of Columbia to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $325. The month of August is another great option to travel to St. Louis, with average flight prices from District of Columbia averaging around $344.

The cheapest day to depart on your flight to St. Louis is on a Wednesday when prices can be found for as low as $347. 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 $461. These prices are subject to change though, so be sure to set up a Price Alert for flights to St. Louis.

Flying to St. Louis from District of Columbia at noon is the least expensive time of day to depart. momondo users have found prices as low as $365 when looking at flights departing at noon. In the afternoon is when there is more demand to fly to St. Louis, so prices are often more expensive at around $410 per ticket.

Fly from Washington, D.C. Reagan-National to Lambert-St Louis for the best District of Columbia - Lambert-St Louis flight prices

There are 4 cabin classes available to choose from on District of Columbia to St. Louis flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

You could potentially save up to 4% on your flight if you consider stops on a District of Columbia to St. Louis flight.

Delta, Southwest, and United Airlines are the most popular carriers operating from District of Columbia to Lambert-St Louis

Southwest, American Airlines and United Airlines are the top three most popular airlines that fly to St. Louis from District of Columbia according to our data. Southwest is the first choice among our users, with 48% of people opting to fly with this airline when traveling to St. Louis. Keep in mind that there are 5 different airlines that fly to St. Louis on a routine basis, so you have a few additional options to choose from.

As of July 2026, there are 13 flights per day flying from District of Columbia to St. Louis. The most common time of day flights depart is 5:00PM, with 45% of flights taking off in the afternoon.

As of July 2026, 96 flights take off from District of Columbia and land in St. Louis each week. The most common flight departure day for this route is Mon, with 16% of weekly flights taking off on this day.