Cheap flights from St. Louis to London from $199
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 London departing on 7/16. 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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How to get the cheapest flight ticket from St. Louis to London
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 London?
The cheapest month to fly to London from St. Louis is in April. Flight prices, which tend to average around $761, are often lower during this time because this is during the off-season. The month of October is another great option to travel to London, with average flight prices from St. Louis averaging around $767.
What is the cheapest day to depart on your flight to London?
The cheapest day to depart from St. Louis to London is on a Wednesday. Travelers who choose to depart for London on a Wednesday will often find tickets for as low as $846. If your travel schedule is flexible, try to avoid departing on a Tuesday because tickets tend to average around $1,006. These prices are subject to change though, so be sure to set up a Price Alert for flights to London.
What is the cheapest time of day to depart on your flight to London?
Flying to London from St. Louis in the morning is the least expensive time of day to depart. momondo users have found prices as low as $915 when looking at flights departing in the morning. Flights to London are more costly at noon, with an average ticket price of $958. Departure times at noon fall within the peak daily travel times, which is why tickets can be more expensive.
How far in advance should I book a flight to London?
You are more likely to see cheaper flights to London from St. Louis when booking 9 weeks ahead of your departure date. In general, you can expect to find flights to London for around $957 when searching 9 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London from St. Louis for as low as $832 on momondo.
Can stopping save me money on St. Louis to London flights?
You could potentially save up to 1% on your flight if you consider stops on a St. Louis to London flight.
How have St. Louis to London flight prices changed over time?
As of June 2025, prices for St. Louis to London flights are approximately 18% cheaper when compared to flights at the same time last year.
What is the cheapest airline that flies from Lambert-St Louis to London?
Air Canada, United Airlines, and Scandinavian Airlines are the most popular carriers operating from Lambert-St Louis to London
What airlines fly to London?
British Airways, American Airlines and United Airlines are the top three most popular airlines that fly to London from St. Louis according to our data. British Airways is the first choice among our users, with 40% of people opting to fly with this airline when traveling to London. Keep in mind that there are 10 different airlines that fly to London on a routine basis, so you have a few additional options to choose from.
When to book flights from St. Louis to London
Cheap St. Louis to London (STL to LON) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from St. Louis to London
How far is Lambert-St Louis to London by plane?
London is 4197.7 mi away from Lambert-St Louis. Flights usually cover this in 10h 14m, depending on flying conditions and air traffic around both airports.
When did momondo last update prices for flights from Lambert-St Louis Airport to London?
Prices for flights from Lambert-St Louis Airport to London were last updated today.
How many operators does momondo search for flights from Lambert-St Louis Airport to London?
As of June 2025, there are 10 operators available to choose from for flights from Lambert-St Louis Airport to London.
How old do you have to be to fly from Lambert-St Louis Airport to London?
Although the minimum age for a child to fly alone is five, airlines that offer an unaccompanied minor (UMNR) service may have their own age limits, which could be impacted by factors such as flight length, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Lambert-St Louis Airport to London.
What documentation or ID do you need to fly to London?
The travel and health documents you'll need for your trip to London may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at London. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular airline from St. Louis to London?
Based on momondo bookings for flights between St. Louis and London, the leading airline is British Airways, making up 28% of the total bookings. Other popular airlines include American Airlines with 22%, United Airlines with 18%, and Iberia with 9%.
Best airlines flying from St. Louis to London
Compare and see reviews for airlines that fly from St. Louis to London with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $651 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $669 | Free Cancellation | Rating 7.3 1,387 reviews | |||
| PriceFrom $671 | Free Cancellation | Rating 7.0 2,776 reviews | |||
| PriceFrom $691 | Free Cancellation | Rating 7.1 9,537 reviews | |||
| PriceFrom $702 | Free Cancellation | Rating 7.4 8,790 reviews | |||
| PriceFrom $703 | Free Cancellation | Rating 7.4 652 reviews | |||
| PriceFrom $704 | Free Cancellation | Rating 6.6 7,008 reviews | |||
| PriceFrom $713 | Free Cancellation | Rating 8.0 7,946 reviews | |||
| PriceFrom $725 | Free Cancellation | Rating 6.7 7,139 reviews | |||
| PriceFrom $726 | Free Cancellation | Rating 7.8 1,358 reviews |
Traveling to a place near London?
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Why should I use momondo to find a flight deal from St. Louis to London?
We help find the flight that best suits your needs, momondo compares prices from hundreds of airlines and travel agents and helps you filter them to find the best flight from St. Louis to London for you.
Can I find flights from St. Louis to London with flexible booking policies on momondo?
momondo does allow users to show only those flights to London from St. Louis which offer a flexible booking policy as well as other useful filters and features.
How can momondo help me find flights from St. Louis to London?
Once you have performed a search for St. Louis to London flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.
I’m not ready to book a flight from St. Louis to London right now. Can momondo alert me if prices change?
If you are not ready to book a flight from St. Louis to London now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to London and let you know when they change.