Cheap flights from St. Louis to London from $283
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 7/21. 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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Lufthansa flights from St. Louis to London Heathrow Airport
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Air Canada flights from St. Louis to London Heathrow Airport
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How to get the cheapest flight ticket from St. Louis to London Heathrow Airport
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 Heathrow Airport?
The month of October is, on average, the cheapest month to fly to London Heathrow Airport from St. Louis, with most prices found around $807. If you’re not able to fly to London Heathrow Airport in October, then March is your next best option. Flight prices from St. Louis to London Heathrow Airport during March average around $829.
What is the cheapest day to depart on your flight to London Heathrow Airport?
Our data shows that Thursday is the least expensive day to fly to London Heathrow Airport. Tickets to fly out on this day can be as low as $906. The most expensive day to fly to London Heathrow Airport is Friday, with ticket prices averaging around $1,015.
What is the cheapest time of day to depart on your flight to London Heathrow Airport?
According to our data, the cheapest time of day to fly to London Heathrow Airport is in the evening. momondo users have found flights departing from St. Louis to London Heathrow Airport in the evening for as low as $895. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights in the morning are often more expensive with an average ticket price of $996.
How far in advance should I book a flight to London Heathrow Airport?
You are more likely to see cheaper flights to London Heathrow Airport from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to London Heathrow Airport for around $954 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London Heathrow Airport from St. Louis for as low as $832 on momondo.
What is the cheapest airline that flies from Lambert-St Louis to London Heathrow?
Air Canada, United Airlines, and Iberia are the most popular carriers operating from Lambert-St Louis to London Heathrow
What airlines fly to London Heathrow Airport?
British Airways, American Airlines and United Airlines are the top three most popular airlines that fly to London Heathrow Airport from St. Louis according to our data. British Airways is the first choice among our users, with 42% of people opting to fly with this airline when traveling to London Heathrow Airport. Keep in mind that there are 10 different airlines that fly to London Heathrow Airport on a routine basis, so you have a few additional options to choose from.
When to book flights from St. Louis to London Heathrow Airport
Cheap St. Louis to London Heathrow Airport (STL to LHR) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from St. Louis to London Heathrow Airport
How far is Lambert-St Louis to London Heathrow by plane?
Lambert-St Louis and London Heathrow are 4185.8 mi apart from one another. By plane, this route typically takes 10h 14m.
When did momondo last update prices for flights from Lambert-St Louis Airport to London Heathrow Airport?
Prices for flights from Lambert-St Louis Airport to London Heathrow Airport were last updated today.
How many operators does momondo search for flights from Lambert-St Louis Airport to London Heathrow Airport?
As of July 2025, there are 10 operators available to choose from for flights from Lambert-St Louis Airport to London Heathrow Airport.
How old do you have to be to fly from Lambert-St Louis Airport to London Heathrow Airport?
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 Heathrow Airport.
What documentation or ID do you need to fly to London Heathrow Airport?
The necessary travel and health documents for your London Heathrow Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.
What is the most popular airline from St. Louis to London Heathrow Airport?
momondo data reveals that the most frequently booked airline on the route from St. Louis to London Heathrow Airport is British Airways, representing 33% of all bookings. The subsequent popular airlines are American Airlines at 24%, United Airlines at 14%, and Iberia at 10%.
Best airlines flying from St. Louis to London Heathrow Airport
Compare and see reviews for airlines that fly from St. Louis to London Heathrow Airport with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $669 | Free Cancellation | Rating 7.3 1,416 reviews | |||
| PriceFrom $671 | Free Cancellation | Rating 7.0 2,819 reviews | |||
| PriceFrom $691 | Free Cancellation | Rating 7.1 9,678 reviews | |||
| PriceFrom $699 | Free Cancellation | Rating 7.4 8,861 reviews | |||
| PriceFrom $703 | Free Cancellation | Rating 7.4 654 reviews | |||
| PriceFrom $704 | Free Cancellation | Rating 6.6 7,093 reviews | |||
| PriceFrom $706 | Free Cancellation | Rating 8.0 7,983 reviews | |||
| PriceFrom $722 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $725 | Free Cancellation | Rating 6.8 7,207 reviews | |||
| PriceFrom $726 | Free Cancellation | Rating 7.8 1,366 reviews |
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Why should I use momondo to find a flight deal from St. Louis to London?
To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to London from St. Louis.
Can I find flights from St. Louis to London with flexible booking policies on momondo?
Flights from St. Louis to London with flexible booking policies can be found by using the search form above and then selecting our dedicated flexible booking filter, which will highlight only the flights where this policy is applied.
How can momondo help me find flights from St. Louis to London?
Once all potential St. Louis to London flight options are in front of you, momondo lets you sort and filter flights based on preferences such as airline, price and flight times amongst many other options.
I’m not ready to book a flight from St. Louis to London right now. Can momondo alert me if prices change?
Yes momondo offers price alerts on flights to London from St. Louis. 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.