Cheap flights from Washington, D.C. Dulles Intl Airport to St. Louis from $90
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Washington, D.C. Dulles Intl Airport to St. Louis departing on 8/31. 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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Delta flights from Washington, D.C. Dulles Intl Airport to St. Louis
Our best Delta deals on Washington, D.C. Dulles Intl Airport to St. Louis flight tickets
American Airlines flights from Washington, D.C. Dulles Intl Airport to St. Louis
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How to get the cheapest flight ticket from Washington, D.C. Dulles Intl Airport to St. Louis
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 St. Louis?
In general, May is the cheapest month to fly from Washington, D.C. Dulles Intl Airport to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $311. The month of February is another great option to travel to St. Louis, with average flight prices from Washington, D.C. Dulles Intl Airport averaging around $325.
What is the cheapest day to depart on your flight to St. Louis?
The cheapest day to depart on your flight to St. Louis is on a Wednesday when prices can be found for as low as $358. 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 $405. These prices are subject to change though, so be sure to set up a Price Alert for flights to St. Louis.
What is the cheapest time of day to depart on your flight to St. Louis?
Flying to St. Louis from Washington, D.C. Dulles Intl Airport at noon is the least expensive time of day to depart. momondo users have found prices as low as $315 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 $385 per ticket.
What is the cheapest Washington, D.C. Dulles Intl to Lambert-St Louis flight route?
Fly from Washington, D.C. Dulles Intl to Lambert-St Louis for the best Washington, D.C. Dulles Intl - Lambert-St Louis flight prices
How far in advance should I book a flight to St. Louis?
You are more likely to see cheaper flights to St. Louis from Washington, D.C. Dulles Intl Airport when booking 18 weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around $412 when searching 18 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to St. Louis from Washington, D.C. Dulles Intl Airport for as low as $303 on momondo.
What cabin class options are available on Washington, D.C. Dulles Intl to Lambert-St Louis flights?
There are 4 cabin classes available to choose from on Washington, D.C. Dulles Intl to Lambert-St Louis 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 Washington, D.C. Dulles Intl Airport to St. Louis flights?
No. A direct flight is the cheapest option for a flight between Washington, D.C. Dulles Intl Airport to St. Louis.
How have Washington, D.C. Dulles Intl Airport to St. Louis flight prices changed over time?
As of June 2025, prices for Washington, D.C. Dulles Intl Airport to St. Louis flights are approximately 10% cheaper when compared to flights at the same time last year.
What is the cheapest airline that flies from Washington, D.C. Dulles Intl to Lambert-St Louis?
United Airlines, Frontier, and Delta are the most popular carriers operating from Washington, D.C. Dulles Intl to Lambert-St Louis
What airlines fly to St. Louis?
United Airlines, Delta and American Airlines are the top three most popular airlines that fly to St. Louis from Washington, D.C. Dulles Intl Airport according to our data. United Airlines is the first choice among our users, with 70% of people opting to fly with this airline when traveling to St. Louis. Keep in mind that there are 3 different airlines that fly to St. Louis on a routine basis, so you have a few additional options to choose from.
How many flights depart from Washington, D.C. Dulles Intl Airport to St. Louis on average per day?
As of June 2025, 8 flights take off from Washington, D.C. Dulles Intl Airport and land in St. Louis each day. The most common flight departure time for this route is 5:00PM, with 65% of daily flights taking off in the afternoon.
How many flights depart from Washington, D.C. Dulles Intl Airport to St. Louis on average per week?
As of June 2025, there are 59 flights per week flying from Washington, D.C. Dulles Intl Airport to St. Louis. The most common day of the week flights depart is Mon, with 15% of flights taking off on this day.
When to book flights from Washington, D.C. Dulles Intl Airport to St. Louis
Cheap Washington, D.C. Dulles Intl Airport to St. Louis (IAD to STL) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Washington, D.C. Dulles Intl Airport to St. Louis
How far is Washington, D.C. Dulles Intl to Lambert-St Louis by plane?
The straight-line distance from Washington, D.C. Dulles Intl to Lambert-St Louis is 685.9 mi. By plane, this route typically takes 2h 19m.
When did momondo last update prices for flights from Washington, D.C. Dulles Intl Airport to Lambert-St Louis Airport?
Prices for flights from Washington, D.C. Dulles Intl Airport to Lambert-St Louis Airport are updated daily.
How many operators does momondo search for flights from Washington, D.C. Dulles Intl Airport to Lambert-St Louis Airport?
As of June 2025, there are 3 operators available to choose from for flights from Washington, D.C. Dulles Intl Airport to Lambert-St Louis Airport.
How old do you have to be to fly from Washington, D.C. Dulles Intl Airport to Lambert-St Louis Airport?
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 Washington, D.C. Dulles Intl Airport to Lambert-St Louis Airport.
What documentation or ID do you need to fly to Lambert-St Louis Airport?
The travel and health documents required for your trip to Lambert-St Louis Airport 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 Lambert-St Louis Airport. 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 Washington, D.C. Dulles Intl Airport to St. Louis?
Based on momondo bookings for flights between Washington, D.C. Dulles Intl Airport and St. Louis, the leading plane model is Canadair (Bombardier) Regional Jet CRJ-550, making up 45.37% of the total bookings. Other popular models include Airbus A319 with 11.11%, Boeing 737-700 Passenger/BBJ1 (winglets) with 11.11%, and Canadair (Bombardier) Regional Jet 700 with 11.11%.
What is the most popular airline from Washington, D.C. Dulles Intl Airport to St. Louis?
Based on momondo bookings for flights between Washington, D.C. Dulles Intl Airport and St. Louis, the leading airline is United Airlines, making up 70% of the total bookings. Other popular airlines include Delta with 24% and American Airlines with 7%.
Best airlines flying from Washington, D.C. Dulles Intl Airport to St. Louis
Compare and see reviews for airlines that fly from Washington, D.C. Dulles Intl Airport to St. Louis with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $202 | Free Cancellation | Rating 8.0 7,964 reviews | |||
| PriceFrom $214 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $259 | Free Cancellation | Rating 7.4 8,809 reviews |
United Airlines Flights From Washington, D.C. Dulles Intl Airport to St. Louis
United Airlines is one of the most popular airlines flying from Washington, D.C. Dulles Intl Airport to St. Louis, operating 17 flights/week on average for this route. A good United Airlines flight deal for Washington, D.C. Dulles Intl Airport to St. Louis starts from $259 round-trip, up to an average price of $478. Our users have rated United Airlines at 7.4/10.
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Why should I use momondo to find a flight deal from Washington, D.C. to St. Louis?
It is quick and easy to find Washington, D.C. to St. Louis flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to St. Louis that suits you.
Can I find flights from Washington, D.C. to St. Louis with flexible booking policies on momondo?
Yes. All flights to St. Louis from Washington, D.C. on momondo can be compared and filtered by various policies on offer, including flexible booking.
How can momondo help me find flights from Washington, D.C. to St. Louis?
momondo provides multiple filters to help you find the best flight to St. Louis from Washington, D.C.. Filter by price, airline, airports, cabin, aircraft, payment method, number of stops and more.
I’m not ready to book a flight from Washington, D.C. to St. Louis right now. Can momondo alert me if prices change?
Yes momondo offers price alerts on flights to St. Louis from Washington, D.C.. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.