£312 Cheap Flights from St. Louis (STL) to Cardiff (CWL)

View £312 flight on Mon, 28 Sept 2026Opens in a new window

Popular airlines from Lambert-St. Louis International Airport (STL) to Cardiff International Airport (CWL)

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Cheap Flights from St. Louis (STL) to Cardiff (CWL)

Prices were available within the past 7 days and start at £312 for one-way flights and for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frequently asked questions

Which airlines fly direct from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.)?
Enter STL to CWL and your travel dates, then apply the 'Nonstop' filter to see only direct flights.
How do I find cheap flights from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.)?
To find a cheap flight from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up Price Tracking and receive alerts when fares go up or down.
What is the best time to fly from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.)?
The best time to fly is usually mid-week (Tuesday or Wednesday) and during early morning hours as flights tend to be cheaper, less crowded, and generally more on-time. Avoid major holidays and peak vacation seasons for smoother travel. Combining off-peak days and hours often gives the best combination of cost, comfort, and convenience.
How many flights per day from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.)?
There are approximately 15 connecting flights per day from St. Louis, MO (STL-Lambert-St. Louis Intl.) (STL) to Cardiff (CWL-Cardiff Intl.) (CWL). Some common connection points include Hartsfield-Jackson Atlanta Intl. (ATL), Minneapolis - St. Paul Intl. (MSP), and Detroit Metropolitan Wayne County (DTW).
What is the earliest flight from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.)?
The earliest flight from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.) typically departs at approximately 6:00 AM local time. This service is operated by Delta and KLM, and it is a seasonal service active in January. An early departure like this can help you maximise your time at your destination. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search.
What day of the week has the most flights from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.)?
When flying from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.), you'll typically find the most flights on a Friday, with around 27 flights available. This gives you plenty of options for your travel plans. Major airlines on this route include Delta, British Airways, and Air Canada. Looking at the overall week, Fridays offer notably more flight options compared to other days.
What are the most popular departure times for flights from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.)?
The most popular departure times for flights from Lambert-St. Louis Intl. (STL) to Cardiff Intl. (CWL) are in the afternoon, from 12pm to 3pm. Approximately 31% of passengers prefer this time window. These times work well because they allow for a relaxed morning before heading to the airport, and you'll arrive at your destination in the evening.
How long does it take to fly from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.)?
A flight from STL to CWL with a layover takes around 21 hours 20 minutes, with the route covering approximately 4,080 miles. Keep in mind that actual flight times can vary due to wind patterns, weather, and air traffic.
Can you fly business or first class from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.)?
Select the "Business class" and "First class" filters when looking for STL to CWL flights on Expedia. This is the easiest way to compare prices, routes and flight times for your trip.
How do I earn miles on a St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.) flight with Expedia?
It's easy to earn miles on a St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of One Key™, you can also earn OneKeyCash™* on top of your airline miles when you book with Expedia. *Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands.
What airports do you fly into for Cardiff from Lambert-St. Louis Intl. (STL)?
If you're planning to travel to Cardiff from Lambert-St. Louis Intl. (STL), you can fly typically into Cardiff Intl. (CWL) Some flights may connect through major hubs like Hartsfield-Jackson Atlanta Intl. (ATL), Pearson Intl. (YYZ), Minneapolis - St. Paul Intl. (MSP) before reaching Cardiff. Compare routes and airports on Expedia to find the best flight options for your travel plans.
Is it cheaper to buy a plane ticket from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.) at the last minute?
Typically, booking a last minute flight from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare.
Is it cheaper to book a St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.) flight and hotel package?
Securing a St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.) flight and hotel package is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.)?
If you booked your St. Louis, MO (STL-Lambert-St. Louis Intl.) to Cardiff (CWL-Cardiff Intl.) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal if you'd like more information.

Travel information

Origin airport
Lambert-St. Louis Intl.
Destination airport
Cardiff Intl.
Distance
6527 km

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