Cheap flights from District of Columbia to St. Louis from $122

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 $72. The month of December is another great option to travel to St. Louis, with average flight prices from District of Columbia averaging around $78.

The cheapest day to depart on your flight to St. Louis is on a Saturday when prices can be found for as low as $353. 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 Sunday because tickets tend to average around $412. 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 in the evening is the least expensive time of day to depart. momondo users have found prices as low as $333 when looking at flights departing in the evening. In the afternoon is when there is more demand to fly to St. Louis, so prices are often more expensive at around $400 per ticket.

Fly from Baltimore/Washington to Lambert-St Louis for the best District of Columbia - Lambert-St Louis flight prices

You are more likely to see cheaper flights to St. Louis from District of Columbia when booking weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around $427 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to St. Louis from District of Columbia for as low as $124 on momondo.

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.

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

Southwest, American Airlines and Frontier 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 49% 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 June 2026, there are 11 flights per day flying from District of Columbia to St. Louis. The most common time of day flights depart is 5:00PM, with 49% of flights taking off in the afternoon.

As of June 2026, 78 flights take off from District of Columbia and land in St. Louis each week. The most common flight departure day for this route is Tue, with 19% of weekly flights taking off on this day.