Cheap flights from St. Louis to Washington, D.C. from $69
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Washington, D.C. departing on 8/25. 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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Frontier flights from St. Louis to Washington, D.C.
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Spirit Airlines flights from St. Louis to Washington, D.C.
Our best Spirit Airlines deals on St. Louis to Washington, D.C. flight tickets
See travel insights to Washington, D.C. from
How to get the cheapest flight ticket from St. Louis to Washington, D.C.
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 Washington, D.C.?
The month of November is, on average, the cheapest month to fly to Washington, D.C. from St. Louis, with most prices found around $229. If you’re not able to fly to Washington, D.C. in November, then August is your next best option. Flight prices from St. Louis to Washington, D.C. during August average around $243.
What is the cheapest day to depart on your flight to Washington, D.C.?
On average, the least expensive day to fly to Washington, D.C. from St. Louis is on a Friday. momondo users have found tickets for Friday departures for as low as $370. However, this price may fluctuate depending on the airline, the season, and holidays. When flying out on a Sunday, the most expensive travel day of the week, you can expect to see flight prices from St. Louis to Washington, D.C. for around $492.
What is the cheapest time of day to depart on your flight to Washington, D.C.?
In the evening is the cheapest time of day to fly from St. Louis to Washington, D.C. when you can find flight prices for as low as $285. Flying to Washington, D.C. in the evening is an ideal time because this is during off-peak travel hours. Try not to purchase tickets at noon because they tend to be around $1,004. Of course, these prices can vary depending on the time of year and what airport you fly to.
What is the cheapest Lambert-St Louis to Washington, D.C. flight route?
Fly from Lambert-St Louis to Washington, D.C. Reagan-National for the best Lambert-St Louis - Washington, D.C. flight prices
How far in advance should I book a flight to Washington, D.C.?
You are more likely to see cheaper flights to Washington, D.C. from St. Louis when booking 12 weeks ahead of your departure date. In general, you can expect to find flights to Washington, D.C. for around $322 when searching 12 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Washington, D.C. from St. Louis for as low as $253 on momondo.
What cabin class options are available on Lambert-St Louis to Washington, D.C. flights?
There are 4 cabin classes available to choose from on Lambert-St Louis to Washington, D.C. flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.
Can stopping save me money on St. Louis to Washington, D.C. flights?
No. A direct flight is the cheapest option for a flight between St. Louis to Washington, D.C..
How have St. Louis to Washington, D.C. flight prices changed over time?
As of June 2025, prices for St. Louis to Washington, D.C. flights are approximately 25% cheaper when compared to flights at the same time last year.
What is the cheapest airline that flies from Lambert-St Louis to Washington, D.C.?
Spirit Airlines, American Airlines, and Southwest are the most popular carriers operating from Lambert-St Louis to Washington, D.C.
What airlines fly to Washington, D.C.?
American Airlines, Southwest and United Airlines are the top three most popular airlines that fly to Washington, D.C. from St. Louis according to our data. American Airlines is the first choice among our users, with 43% of people opting to fly with this airline when traveling to Washington, D.C.. Keep in mind that there are 5 different airlines that fly to Washington, D.C. on a routine basis, so you have a few additional options to choose from.
How many flights depart from St. Louis to Washington, D.C. on average per day?
The number of flights available between St. Louis and Washington, D.C. is 16 per day as of June 2025. The most frequent departure time is 8:00AM, with 48% of daily flights leaving at noon.
How many flights depart from St. Louis to Washington, D.C. on average per week?
The number of flights available between St. Louis and Washington, D.C. is 115 per week as of June 2025. The most frequent departure day is Mon, with 19% of weekly flights leaving on this day.
When to book flights from St. Louis to Washington, D.C.
Cheap St. Louis to Washington, D.C. (STL to WAS) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from St. Louis to Washington, D.C.
Best Price Found | $69 |
|---|---|
Fastest flight time | 1h 55m |
Direct flights | Every day |
Airports in Washington, D.C. | 3 airports |
How far is Lambert-St Louis to Washington, D.C. by plane?
A flight from Lambert-St Louis to Washington, D.C. will travel around 708.3 mi. By plane, this route typically takes 1h 55m.
When did momondo last update prices for flights from Lambert-St Louis Airport to Washington, D.C.?
Prices for flights from Lambert-St Louis Airport to Washington, D.C. are updated daily.
How many operators does momondo search for flights from Lambert-St Louis Airport to Washington, D.C.?
The number of operators available for flights from Lambert-St Louis Airport to Washington, D.C. is 5 as of June 2025.
How old do you have to be to fly from Lambert-St Louis Airport to Washington, D.C.?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Lambert-St Louis Airport to Washington, D.C..
What documentation or ID do you need to fly to Washington, D.C.?
The travel and health documents required for your trip to Washington, D.C. can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Washington, D.C.. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular plane model from St. Louis to Washington, D.C.?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from St. Louis to Washington, D.C. is Boeing 737-700 Passenger/BBJ1 (winglets) (18.83% of total bookings). The next most popular plane models are Boeing 737 MAX 8 (17.35%), Boeing 737-800 Passenger/BBJ2 (winglets) (16.15%), and Canadair (Bombardier) Regional Jet 700 (14.90%).
What is the most popular airline from St. Louis to Washington, D.C.?
Based on momondo bookings for flights between St. Louis and Washington, D.C., the leading airline is Southwest, making up 47% of the total bookings. Other popular airlines include American Airlines with 43%, United Airlines with 6%, and Delta with 2%.
Best airlines flying from St. Louis to Washington, D.C.
Compare and see reviews for airlines that fly from St. Louis to Washington, D.C. with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $120 | Free Cancellation | Rating 5.9 3,295 reviews | |||
| PriceFrom $129 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $176 | Free Cancellation | Rating 8.0 7,950 reviews | |||
| PriceFrom $197 | Free Cancellation | Rating 8.0 4,287 reviews | |||
| PriceFrom $209 | Free Cancellation | Rating 7.4 8,790 reviews |
Southwest Flights From St. Louis to Washington, D.C.
Southwest operates around 26 flights from St. Louis to Washington, D.C. every week. The average price of these flights found in the last 72 hours has been $332, but momondo users have found Southwest deals from St. Louis to Washington, D.C. from as low as $197 round-trip. Southwest has been scored 8.0/10 in 4,287 reviews.
United Airlines Flights From St. Louis to Washington, D.C.
The best United Airlines deal for St. Louis to Washington, D.C. flight tickets found on momondo in the last 72 hours was $209, round-trip. It should be noted that an average United Airlines flight deal for this route in this time was higher, at $392 round-trip. United Airlines operates 14 flights out of St. Louis into Washington, D.C. in an average week, so prices vary by time and availability. 8,790 United Airlines reviews by users on momondo have scored the airline at 7.4/10.
Traveling to a place near Washington, D.C.?
Book flights to Washington, D.C. if you plan to visit one of these locationsWhy use momondo?
Why should I use momondo to find a flight deal from St. Louis to Washington, D.C.?
momondo collates all your flight options in one place and lets you filter them to find the perfect flight from St. Louis to Washington, D.C.. momondo saves you time and could save you money on your trip.
Can I find flights from St. Louis to Washington, D.C. with flexible booking policies on momondo?
Yes. All flights to Washington, D.C. from St. Louis on momondo can be compared and filtered by various policies on offer, including flexible booking.
How can momondo help me find flights from St. Louis to Washington, D.C.?
momondo provides multiple filters to help you find the best flight to Washington, D.C. from St. Louis. Filter by price, airline, airports, cabin, aircraft, payment method, number of stops and more.
I’m not ready to book a flight from St. Louis to Washington, D.C. right now. Can momondo alert me if prices change?
Of course. momondo tracks the price of St. Louis to Washington, D.C. flights. All you need is a valid email address and we will do the rest; it is that quick and easy.