$403 Cheap Flights from St. Louis (STL) to London (LHR)

View $403 flight on Tue, May 12, 2026Opens in a new window

Popular airlines from St. Louis Lambert Intl. Airport (STL) to Heathrow Airport (LHR)

Cheap Flights from St. Louis to London (STL-LHR)

Prices were available within the past 7 days and start at $403 for one-way flights and $547 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Virgin Atlantic
Wed, Mar 4 - Tue, Mar 10
STL
St. Louis
LHR
London
$547 Roundtrip, found 15 hours ago
$547
Roundtrip
found 15 hours ago
Select Virgin Atlantic flight, departing Wed, Mar 4 from St. Louis to London, returning Tue, Mar 10, priced at $547 found 15 hours ago
Delta
Wed, Mar 4 - Tue, Mar 10
STL
St. Louis
LHR
London
$547 Roundtrip, found 15 hours ago
$547
Roundtrip
found 15 hours ago
Select Delta flight, departing Wed, Mar 4 from St. Louis to London, returning Tue, Mar 10, priced at $547 found 15 hours ago
British Airways
Wed, Mar 4 - Tue, Mar 10
STL
St. Louis
LHR
London
$547 Roundtrip, found 15 hours ago
$547
Roundtrip
found 15 hours ago
Select British Airways flight, departing Wed, Mar 4 from St. Louis to London, returning Tue, Mar 10, priced at $547 found 15 hours ago
Virgin Atlantic
Wed, Mar 4 - Tue, Mar 10
STL
St. Louis
LHR
London
$547 Roundtrip, found 15 hours ago
$547
Roundtrip
found 15 hours ago
Select Virgin Atlantic flight, departing Wed, Mar 4 from St. Louis to London, returning Tue, Mar 10, priced at $547 found 15 hours ago
United
Wed, Mar 4 - Tue, Mar 10
STL
St. Louis
LHR
London
$547 Roundtrip, found 15 hours ago
$547
Roundtrip
found 15 hours ago
Select United flight, departing Wed, Mar 4 from St. Louis to London, returning Tue, Mar 10, priced at $547 found 15 hours ago
American Airlines
Wed, Mar 4 - Tue, Mar 10
STL
St. Louis
LHR
London
$547 Roundtrip, found 15 hours ago
$547
Roundtrip
found 15 hours ago
Select American Airlines flight, departing Wed, Mar 4 from St. Louis to London, returning Tue, Mar 10, priced at $547 found 15 hours ago
Air Canada
Wed, Mar 4 - Tue, Mar 10
STL
St. Louis
LHR
London
$549 Roundtrip, found 15 hours ago
$549
Roundtrip
found 15 hours ago
Select Air Canada flight, departing Wed, Mar 4 from St. Louis to London, returning Tue, Mar 10, priced at $549 found 15 hours ago
United
Wed, Mar 4 - Tue, Mar 10
STL
St. Louis
LHR
London
$562 Roundtrip, found 15 hours ago
$562
Roundtrip
found 15 hours ago
Select United flight, departing Wed, Mar 4 from St. Louis to London, returning Tue, Mar 10, priced at $562 found 15 hours ago
Delta
Wed, Mar 4 - Tue, Mar 10
STL
St. Louis
LHR
London
$573 Roundtrip, found 15 hours ago
$573
Roundtrip
found 15 hours ago
Select Delta flight, departing Wed, Mar 4 from St. Louis to London, returning Tue, Mar 10, priced at $573 found 15 hours ago
Air Canada
Sat, Apr 25 - Mon, May 4
STL
St. Louis
LHR
London
$588 Roundtrip, found 6 days ago
$588
Roundtrip
found 6 days ago
Select Air Canada flight, departing Sat, Apr 25 from St. Louis to London, returning Mon, May 4, priced at $588 found 6 days ago

Find the cheapest month to fly from St. Louis (STL) to London (LHR)

September is typically the cheapest month to fly

From $518 - $1,507 per traveler.

Alternative airports near London

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to London City LCY. Closest option available. Average driving time to city center is 21 minutes. Flights from $944
LCY
London City
Closest
Average driving time to city center21 min
Flights from $944

Frequently asked questions

How much does a flight from Lambert-St. Louis Intl. Airport (STL) to Heathrow Airport (LHR) cost?
Snag a cheap one-way flight from $403 or cheap return flight from $547 from Lambert-St. Louis Intl. Airport (STL) to Heathrow Airport (LHR) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to find our cheapest flight deals on this route.
What is the cheapest month to fly from Lambert-St. Louis Intl. Airport (STL) to Heathrow Airport (LHR)?
Planning your trip for March may help you find better deals, as it's the cheapest month for flights between STL and LHR. You'll typically find the lowest prices during the off-season.
What is the cheapest airline that flies from Lambert-St. Louis Intl. Airport (STL) to Heathrow Airport (LHR)?
Use the filters on Expedia to compare airlines and find the most affordable carrier that'll fly you from STL to LHR. Then, sort your results by "Price (lowest to highest)" to snap up the best deal available.
How many flights per day from Lambert-St. Louis Intl. Airport (STL) to Heathrow Airport (LHR)?
Direct flights from Lambert-St. Louis Intl. Airport (STL) to Heathrow Airport (LHR) aren't available daily, so you'll need to take a flight with a layover. Explore your options with our filter tool. Enter your dates and select either "1 Stop" or "2+ Stops."
What day of the week has the most flights from STL to LHR?
Friday is typically the busiest day for flights, while Tuesday is often the quietest.* Remember that flight schedules can vary depending on various factors, including the time of year and carrier.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Lambert-St. Louis Intl. Airport (STL) to Heathrow Airport (LHR)?
Select a flight from Lambert-St. Louis Intl. Airport (STL) to Heathrow Airport (LHR) that leaves before 3 PM to reduce the risk of cancellations. Departures after this hour are on average 22% more likely to be canceled.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
Is it cheaper to buy a plane ticket from Lambert-St. Louis Intl. Airport (STL) to Heathrow Airport (LHR) last-minute?
Booking your flight from STL to LHR shortly before your getaway is generally more expensive. However, if you're flexible with your itinerary, you could score a cheap last-minute fare.
Is it cheaper to book a STL to LHR flight and hotel package?
Compared with arranging hotels and flights separately, booking a STL to LHR flight and hotel package with Expedia could lead to significant savings. Better still, having it all in one place will take the hassle out of travel planning. Simply secure your flights and select from our wide range of hotels, then personalize your trip with extras like activities and car rentals.
Can I cancel or change the date of my flight from Lambert-St. Louis Intl. Airport (STL) to Heathrow Airport (LHR)?
If you reserved your STL to LHR flight in the last 24 hours, you may be able to modify or cancel it at no cost. Depending on the airline and the fare type you purchased, additional charges may apply for changes beyond that time. Airline policies and contact information can be found in your itinerary or confirmation email. Or, go to our Customer Service portal if you want more information.

Travel information

Origin airport
Lambert-St. Louis Intl.
Destination airport
Heathrow
Airlines serving
Aer Lingus, Air Canada, Air France, American Airlines, Austrian Airlines, British Airways, Brussels Airlines, Delta, Finnair, Iberia, KLM, Lufthansa, Scandinavian Airlines, United, Virgin Atlantic
Roundtrip price
$546
Distance
4189 mi

Book with confidence

St. Louis to London Flights

The cheapest times to fly from St. Louis to London

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from St. Louis to London are during the month of March. You can find some of the cheapest flights from St. Louis to London with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from St. Louis to London

Sunday is one of the best days to book for cheap flights from St. Louis to London: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from St. Louis to London

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from St. Louis to London in 2025. You can also book with separate airlines for your outbound and return journeys, from $403 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap St. Louis to London flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your St. Louis to London airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

St. Louis to London Flights

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*Available to One Key members.