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$320+ Cheap flights from St. Louis (STL) to London (LON)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 8/4. Fares are subject to change and may not be available on all flights or dates of travel.
STL — LON
Jun 5 — Jun 121
Fri 6/5
Fri 6/12
1 adult, Economy
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Cheapflights Tip: The best prices from Lambert-St Louis to London are usually found in January or October, booked 12 days in advance, depart on a Thursday or Tuesday and return on a Monday

Cheap flight deals from St. Louis to London

Cheapest flights from St. Louis to London
Explore the most affordable flight options available from St. Louis to London. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 6, 2026.

This Kiwi.com deal was found by Cheapflights users on 5/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/168:08 pm
STL
-
LGW
2 stops31h 52m
Multiple Airlines
Tue 9/12:00 pm
LGW
-
STL
1 stop16h 14m
Multiple Airlines
Deal found 5/3$853
This Kiwi.com deal was found by Cheapflights users on 5/4. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/274:52 pm
STL
-
LGW
2 stops35h 08m
Multiple Airlines
Wed 8/192:00 pm
LGW
-
STL
1 stop16h 14m
Multiple Airlines
Deal found 5/4$854
This Kiwi.com deal was found by Cheapflights users on 5/4. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/254:52 pm
STL
-
LGW
2 stops35h 08m
Multiple Airlines
Tue 8/182:00 pm
LGW
-
STL
1 stop16h 14m
Multiple Airlines
Deal found 5/4$858
This Travelocity deal was found by Cheapflights users on 5/4. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Travelocity is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/299:35 pm
STL
-
LHR
Nonstop8h 00m
Iberia
Wed 10/146:15 am
LHR
-
STL
2 stops19h 53m
Iberia
Deal found 5/4$859
This oojo deal was found by Cheapflights users on 5/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/79:35 pm
STL
-
LHR
Nonstop8h 00m
British Airways
Thu 10/157:50 am
LHR
-
STL
2 stops18h 18m
British Airways
Deal found 5/1$866
This Delta deal was found by Cheapflights users on 5/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/87:05 pm
STL
-
LHR
1 stop12h 10m
Delta
Wed 9/166:30 am
LHR
-
STL
2 stops16h 25m
Delta
Deal found 5/1$868
This Delta deal was found by Cheapflights users on 5/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/66:00 am
STL
-
LHR
1 stop19h 15m
Delta
Fri 10/166:30 am
LHR
-
STL
2 stops16h 36m
Delta
Deal found 5/5$869
This Cheapflightsfares deal was found by Cheapflights users on 5/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/69:35 pm
STL
-
LHR
Nonstop8h 00m
British Airways
Fri 10/164:25 pm
LHR
-
STL
Nonstop9h 05m
British Airways
Deal found 5/5$870
This Expedia deal was found by Cheapflights users on 5/3. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/169:40 pm
STL
-
LHR
Nonstop8h 00m
Multiple Airlines
Tue 9/16:30 am
LHR
-
STL
1 stop12h 55m
Multiple Airlines
Deal found 5/3$871
This Kiwi.com deal was found by Cheapflights users on 5/4. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 7/274:52 pm
STL
-
LGW
2 stops35h 08m
Multiple Airlines
Tue 8/182:00 pm
LGW
-
STL
1 stop16h 14m
Multiple Airlines
Deal found 5/4$871
This Delta deal was found by Cheapflights users on 5/1. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/21:30 pm
STL
-
LHR
2 stops14h 50m
Delta
Tue 9/89:55 am
LHR
-
STL
2 stops16h 36m
Delta
Deal found 5/1$872
This Delta deal was found by Cheapflights users on 5/5. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/611:51 am
STL
-
LHR
2 stops13h 19m
Delta
Wed 10/146:30 am
LHR
-
STL
2 stops17h 31m
Delta
Deal found 5/5$873

Find flight deals from St. Louis to London

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to London (LON). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated May 6, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$853
(Kiwi.com)

One-way from

$320
(Cheapflightsfares)

Popular in

June

Cheapest in

January

Average price

$1,003

Good round-trip deal

$1,067 or less

Good one-way deal

$514 or less
Provider with most accurate pricing for Lambert-St Louis-London (LON) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Lambert-St Louis-London (LON) flights.
Search Deals
From Lambert-St Louis to London (LON)
Search Deals
One-way flight from Lambert-St Louis to London (LON)
Search Deals
Highest demand for flights based on searches. 25% potential increase in price ($298 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 5% potential price decrease ($44 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in May 2026
Search Deals
Price to beat on a round-trip flight from Lambert-St Louis to London (LON).
Search Deals
Price to beat on a one-way flight from Lambert-St Louis to London (LON).
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to London that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated May 6, 2026.
Use the filters below to find and compare flights from St. Louis to London that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 8/25

6:00 am-6:25 am

1 stop18h 25m

London Heathrow

Tue 9/1

6:30 am-6:02 pm

2 stops17h 32m

$868

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 8/19

3:39 pm-1:15 pm

1 stop15h 36m

London Heathrow

Tue 8/25

6:30 am-3:10 pm

2 stops14h 40m

$868

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 10/21

9:00 am-7:15 am

1 stop16h 15m

London Heathrow

Fri 10/30

6:30 am-6:01 pm

2 stops16h 31m

$869

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 9/8

7:20 am-7:10 am

2 stops17h 50m

London Heathrow

Tue 9/22

9:55 am-8:50 pm

2 stops16h 55m

$873

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 9/16

10:45 am-8:50 am

2 stops16h 05m

London Heathrow

Fri 9/25

6:30 am-4:55 pm

2 stops16h 25m

$873

St. LouisLondon

STL - LCY

STLLCY

Lambert-St Louis

Wed 9/2

1:30 pm-8:50 am

2 stops13h 20m

London City

Fri 9/11

9:20 am-8:50 pm

2 stops17h 30m

$897

St. LouisLondon

STL - LCY

STLLCY

Lambert-St Louis

Wed 9/2

1:30 pm-8:50 am

2 stops13h 20m

London City

Tue 9/8

10:00 am-8:50 pm

2 stops16h 50m

$897

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 8/26

5:30 pm-1:05 pm

1 stop13h 35m

London Heathrow

Sun 9/6

6:30 am-4:45 pm

2 stops16h 15m

$918
Quickest round-trip

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Fri 9/11

4:13 pm-10:20 am

1 stop12h 07m

London Heathrow

Tue 9/22

9:55 am-8:50 pm

2 stops16h 55m

$919

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Sat 9/5

10:45 am-10:20 am

2 stops17h 35m

London Heathrow

Fri 9/25

6:30 am-4:55 pm

2 stops16h 25m

$923

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/2

Showing 1-10 of 60 resultsSorted by cheapest first
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Compare providers for flights from St. Louis to London

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from St. Louis to London in May.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars
OvagoPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy3 starsTrust Score*3 stars
JustAirTicketPrice Accuracy-Trust Score*1 star
Trip.comPrice Accuracy1 starTrust Score*3 stars
Justfly.comPrice Accuracy3 starsTrust Score*3 stars
GurufarePrice Accuracy3 starsTrust Score*3 stars
BusinessClassPrice Accuracy-Trust Score*3 stars
CheapflightsfaresPrice Accuracy2 starsTrust Score*1 star

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on St. Louis-London flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on St. Louis-London flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from St. Louis-London flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on St. Louis-London flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for St. Louis-London flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from St. Louis to London

Have a flexible travel schedule? Discover the best time to fly to London from St. Louis with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to London

How far ahead should I book a flight from St. Louis to London?

The best time to book flights from St. Louis to London is 5 days before your desired departure date. The cost of your flight will likely increase significantly if you book two weeks in advance of your flight.

What is the cheapest month to book a flight from St. Louis to London?

Currently, April is the cheapest month in which you can book a flight from St. Louis to London (average of $117). Flying from St. Louis to London in June is currently the most expensive (average of $824). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from STL to LON?

Find hourly flight availability from St. Louis to London. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated May 6, 2026.

When flying from St. Louis to London, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

How much does it cost to fly round-trip from St. Louis to London?

What’s the top layover airport for flights from St. Louis to London?

Share of 1-stop round-trip flights from St. Louis to London chosen by Cheapflights users in the past 12 months, using the same layover each way.

Montreal (YUL) – chosen by Cheapflights users on 67% of 1-stop itineraries from St. Louis to London on Cheapflights.

What’s the cheapest layover airport for flights from St. Louis to London?

Average round-trip fare for 1-stop flights from St. Louis to London, chosen by Cheapflights users in the past 12 months, with the same layover each way.

Chicago (ORD) is the most affordable 1-stop option, with an average round-trip price of $808.

What’s the fastest layover option from St. Louis to London?

Shortest average travel time for 1-stop one-way flights from St. Louis to London, based on itineraries clicked by Cheapflights users over the past 12 months, grouped by layover airport.

Flights via Chicago (ORD) have the shortest average one-way travel time for 1-stop routes: 9h 43m.

Which airport typically offers the quickest layover for flights from St. Louis to London?

Average layover duration for 1-stop one-way flights from St. Louis to London, chosen by Cheapflights users in the last 12 months, grouped by stopover airport.

Flights via Chicago (ORD) offer the fastest connection on this route, with an average layover time of 1h 16m.

Reviews of airlines servicing London

Get insights into the airlines that provide service to London. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to London. Reviews last updated May 6, 2026.
Read reviews from past customers who have flown Delta,United Airlines, andAmerican Airlines from St. Louis to London. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
7.9
Good
8,459 reviews

Crew

8.5

Food

7.2

Boarding

8.1

Comfort

7.9

Overall

7.9

Entertainment

7.8

Reviews

1 / 20
4.0
Okay

Joel,May 2026

ATL - JAX

The flight was delivered 50 minutes and taxing took what felt like 20 minutes to takeoff.
Delta
7.9
Good
8,459 reviews
Delta
7.9
Good
8,459 reviews

Crew

8.5

Food

7.2

Boarding

8.1

Comfort

7.9

Overall

7.9

Entertainment

7.8

Reviews

1 / 20
4.0
Okay

Joel,May 2026

ATL - JAX

The flight was delivered 50 minutes and taxing took what felt like 20 minutes to takeoff.
United Airlines
7.4
Good
9,684 reviews
Delta
7.9
Good
8,459 reviews

Crew

8.5

Food

7.2

Boarding

8.1

Comfort

7.9

Overall

7.9

Entertainment

7.8

Reviews

1 / 20
4.0
Okay

Joel,May 2026

ATL - JAX

The flight was delivered 50 minutes and taxing took what felt like 20 minutes to takeoff.
American Airlines
7.1
Good
11,672 reviews
Delta
7.9
Good
8,459 reviews

Crew

8.5

Food

7.2

Boarding

8.1

Comfort

7.9

Overall

7.9

Entertainment

7.8

Reviews

1 / 20
4.0
Okay

Joel,May 2026

ATL - JAX

The flight was delivered 50 minutes and taxing took what felt like 20 minutes to takeoff.
Air Canada
7.1
Good
11,000 reviews
Delta
7.9
Good
8,459 reviews

Crew

8.5

Food

7.2

Boarding

8.1

Comfort

7.9

Overall

7.9

Entertainment

7.8

Reviews

1 / 20
4.0
Okay

Joel,May 2026

ATL - JAX

The flight was delivered 50 minutes and taxing took what felt like 20 minutes to takeoff.
British Airways
6.7
Okay
7,944 reviews
Delta
7.9
Good
8,459 reviews

Crew

8.5

Food

7.2

Boarding

8.1

Comfort

7.9

Overall

7.9

Entertainment

7.8

Reviews

1 / 20
4.0
Okay

Joel,May 2026

ATL - JAX

The flight was delivered 50 minutes and taxing took what felt like 20 minutes to takeoff.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to London. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from St. Louis to London?

    Lambert-St Louis (STL) is the airport you will fly out of if you book a flight from St. Louis to London. You should not have trouble finding flights to London from Lambert-St Louis; the airport handles an average of 2 outbound flights to London per day. You should also have plenty of airline options to choose from since 8 airlines have flights from the St. Louis airport to London. It is only a 12.7 mi journey to Lambert-St Louis (STL) from St. Louis’s city center.

  • How long is the flight from St. Louis to London?

    A quick flight from St. Louis to London can take about 18h 25m. Delta provides one of the quickest options available for as low as $868. St. Louis and London are separated by a distance of 4186 mi.

  • What are the cheapest airlines flying from St. Louis to London round-trip?

    According to our current data, Delta ($483), KLM ($529), and American Airlines ($563) offers the cheapest pricing from St. Louis to London. These flights start at 44% lower than the current average price 3 months from now.

  • What are the cheapest airlines to fly from St. Louis to London one-way?

    The cheapest airline one-way is Iberia, with whom users have recently found tickets for as low as $317. However, be on the lookout for offers from British Airways and Air Canada, as they are both options that can get you from St. Louis to London for a low price.

  • What are the most popular routes from St. Louis to London?

    The most popular flight routes from St. Louis to London are Lambert-St Louis - London Heathrow, Lambert-St Louis - London Gatwick and Lambert-St Louis - London Stansted.

  • What are the most reliable airlines from St. Louis to London?

    Looking for the most reliable airlines to get you to your destination on time? Our data shows these are most likely to get you from St. Louis to London on time: American Airlines (14%), Aer Lingus (14%), Finnair (14%).

  • What are the cheapest flights from St. Louis to London?

    The cheapest flight price from St. Louis to London is $388. On average you can expect to pay $1,587. The most popular route, (Lambert-St Louis - London Heathrow), can usually be booked for $856.

  • Can I find deals for flights from St. Louis to London that include hotel bookings?

    Yes. In addition to deals on St. Louis to London flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from St. Louis to London?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to London.

  • Can I find deals for business class flights from St. Louis to London?

    Yes. Cheapflights offers flight deals from St. Louis to London by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from St. Louis to London?

    Currently, April is the cheapest month in which you can book a flight from St. Louis to London (average of $117). Flying from St. Louis to London in June is currently the most expensive (average of $824). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Traveling to a place near London?

Book flights to London if you plan to visit one of these locations
Ilford
Hounslow
Winchester
Croydon
Gatwick
Southend-on-Sea
Harrow
Eastleigh
Dartford
Dover
Orpington
Watford
Borehamwood
Chipping Norton
Hayes
Kingston upon Thames
Eastbourne
Slough
Sutton
Stansted

Browse thousands of different options on Cheapflights for your next trip

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Top 8 airlines flying from St. Louis to London

Discover the top 8 airlines that operate flights from St. Louis to London. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated May 6, 2026.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$483Average$852FlexibilityNo cancel feeOn-timeN/A
KLMCheapest$529Average$643FlexibilityNo cancel feeOn-time75%
American AirlinesCheapest$563Average$867FlexibilityNo cancel feeOn-time71%
Air CanadaCheapest$572Average$863FlexibilityNo cancel feeOn-time67%
British AirwaysCheapest$574Average$853FlexibilityNo cancel feeOn-time70%
IberiaCheapest$577Average$823FlexibilityNo cancel feeOn-time77%
United AirlinesCheapest$580Average$838FlexibilityNo cancel feeOn-time69%
LufthansaCheapest$635Average$962FlexibilityNo cancel feeOn-time76%

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