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$231+ 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 10/4. Fares are subject to change and may not be available on all flights or dates of travel.
STL — LON
Oct 11 — Oct 181
Sat 10/11
Sat 10/18
1 adult, Economy
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Cheapflights Tip: The best prices from Lambert-St Louis to London are usually found in October or April, booked 81 days in advance, depart on a Wednesday or Thursday and return on a Wednesday

Cheap 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 September 11, 2025.

Round-trip from

$528
(United Airlines)

One-way from

$231
(Kiwi.com)

Popular in

June

Cheapest in

October

Average price

$818
From Lambert-St Louis to London (LON)
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One-way flight from Lambert-St Louis to London (LON)
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Highest demand for flights based on searches. 21% potential increase in price ($251 potential increase over avg. RT price).
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Cheapest flight prices on average. 4% potential price decrease ($38 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Find 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 September 11, 2025.

This United Airlines deal was found by Cheapflights users on 9/11. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/116:43 pmSTL - LHR
1 stop10h 32mUnited Airlines
Tue 11/186:00 pmLHR - STL
1 stop27h 29mUnited Airlines
Deal found 9/11$528
This United Airlines deal was found by Cheapflights users on 9/11. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/1911:49 amSTL - LHR
1 stop12h 31mUnited Airlines
Fri 12/56:30 amLHR - STL
1 stop13h 25mUnited Airlines
Deal found 9/11$529
This Air Canada deal was found by Cheapflights users on 9/9. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/114:05 pmSTL - LHR
2 stops33h 05mAir Canada
Tue 11/181:25 pmLHR - STL
2 stops32h 04mAir Canada
Deal found 9/9$530
This United Airlines deal was found by Cheapflights users on 9/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/64:05 pmSTL - LHR
2 stops22h 30mUnited Airlines
Fri 12/197:40 amLHR - STL
1 stop17h 58mUnited Airlines
Deal found 9/10$534
This Air Canada deal was found by Cheapflights users on 9/10. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/211:30 pmSTL - LHR
2 stops14h 45mAir Canada
Tue 10/76:50 amLHR - STL
2 stops14h 28mAir Canada
Deal found 9/10$541
This Netflights deal was found by Cheapflights users on 9/9. 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 Netflights is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/246:52 pmSTL - LHR
1 stop12h 38mVirgin Atlantic
Tue 11/48:55 amLHR - STL
1 stop15h 07mVirgin Atlantic
Deal found 9/9$548
This Ovago deal was found by Cheapflights users on 9/10. 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 Ovago is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/67:36 pmSTL - LHR
1 stop29h 19mBritish Airways
Fri 12/1912:35 pmLHR - STL
1 stop12h 56mBritish Airways
Deal found 9/10$550
This Air Canada deal was found by Cheapflights users on 9/10. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/211:30 pmSTL - LHR
2 stops14h 45mAir Canada
Wed 10/19:30 amLHR - STL
2 stops16h 08mAir Canada
Deal found 9/10$551
This Flightnetwork deal was found by Cheapflights users on 9/9. 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 Flightnetwork is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/249:15 amSTL - LHR
2 stops15h 15mAir Canada
Fri 10/316:00 pmLHR - STL
1 stop26h 29mAir Canada
Deal found 9/9$553
This American Airlines deal was found by Cheapflights users on 9/11. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/259:07 amSTL - LGW
2 stops15h 28mAmerican Airlines
Thu 10/910:40 amLGW - STL
2 stops19h 14mAmerican Airlines
Deal found 9/11$580
This Air Canada deal was found by Cheapflights users on 9/10. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/24:05 pmSTL - LCY
2 stops14h 45mMultiple Airlines
Tue 12/99:50 amLCY - STL
2 stops35h 39mMultiple Airlines
Deal found 9/10$582
This Kiwi.com deal was found by Cheapflights users on 9/11. 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 12/135:11 pmSTL - LGW
1 stop34h 49mMultiple Airlines
Sat 1/102:00 pmLGW - STL
1 stop14h 33mMultiple Airlines
Deal found 9/11$606

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 September 11, 2025.
Use the filters below to find and compare flights from St. Louis to London that are best for you.

Fly from

St. Louis

Fly to

London

Route

Depart

Return

Price

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 11/11

6:43 pm-11:15 am

1 stop10h 32m

London Heathrow

Tue 11/18

6:00 pm-3:29 pm

1 stop27h 29m

$528

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Tue 10/14

10:45 am-8:50 am

2 stops16h 05m

London Heathrow

Wed 10/22

9:55 am-10:04 pm

2 stops18h 09m

$528

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Fri 11/7

4:05 pm-8:35 pm

2 stops46h 30m

London Heathrow

Wed 11/19

6:00 pm-3:29 pm

1 stop27h 29m

$529

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Wed 11/19

11:49 am-6:20 am

1 stop12h 31m

London Heathrow

Fri 12/5

6:30 am-1:55 pm

1 stop13h 25m

$529

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Thu 10/16

11:10 am-11:45 am

1 stop18h 35m

London Heathrow

Fri 10/24

8:40 am-7:42 pm

2 stops17h 02m

$563

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Fri 11/7

5:24 pm-5:55 am

1 stop30h 31m

London Heathrow

Wed 11/19

11:10 am-3:29 pm

1 stop34h 19m

$565

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Sun 10/26

6:43 pm-5:55 am

1 stop30h 12m

London Heathrow

Sun 11/2

11:10 am-3:29 pm

1 stop34h 19m

$566

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Fri 10/17

5:15 am-12:20 pm

1 stop25h 05m

London Heathrow

Tue 10/21

5:40 pm-3:18 pm

1 stop27h 38m

$567

St. LouisLondon

STL - LHR

STLLHR

Lambert-St Louis

Mon 9/29

5:15 am-12:20 pm

1 stop25h 05m

London Heathrow

Mon 10/6

5:40 pm-7:38 pm

1 stop31h 58m

$567

St. LouisLondon

STL - LGW

STLLGW

Lambert-St Louis

Thu 9/25

9:07 am-6:35 am

2 stops15h 28m

London Gatwick

Thu 10/9

10:40 am-11:54 pm

2 stops19h 14m

$580

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/11

Showing 1-10 of 60 results
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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?

Use this chart to determine the optimal time to book a round-trip flight from St. Louis to London. Price data was last updated on August 29, 2025.

The best time to book flights from St. Louis to London is 81 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, November is the cheapest month in which you can book a flight from St. Louis to London (average of $661). Flying from St. Louis to London in June is currently the most expensive (average of $1,098). 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 September 11, 2025.

It’s optimal to fly from St. Louis to London in the morning. By choosing this option you can save up to 5% on the cost of your flight, compared to a flight at noon.

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.

Chicago (ORD) – chosen by Cheapflights users on 62% 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 $730.

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: 10h 06m.

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 31m.

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 September 11, 2025.
Read reviews from past customers who have flown United Airlines, American Airlines, and Air Canada 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.
United Airlines
7.4
Good
8,937 reviews

Overall

7.4

Entertainment

7.1

Comfort

7.3

Crew

8.1

Food

6.6

Boarding

7.7

Reviews

1 / 20
4.0
Okay

Thomas,Mar 2025

SFO - TPE

When I asked for an extra snack, I got an unhappy look from the stewardess. Geez, does one extra snack really affect the bottom line??
United Airlines
7.4
Good
8,937 reviews
United Airlines
7.4
Good
8,937 reviews

Overall

7.4

Entertainment

7.1

Comfort

7.3

Crew

8.1

Food

6.6

Boarding

7.7

Reviews

1 / 20
4.0
Okay

Thomas,Mar 2025

SFO - TPE

When I asked for an extra snack, I got an unhappy look from the stewardess. Geez, does one extra snack really affect the bottom line??
American Airlines
7.2
Good
10,000 reviews
United Airlines
7.4
Good
8,937 reviews

Overall

7.4

Entertainment

7.1

Comfort

7.3

Crew

8.1

Food

6.6

Boarding

7.7

Reviews

1 / 20
4.0
Okay

Thomas,Mar 2025

SFO - TPE

When I asked for an extra snack, I got an unhappy look from the stewardess. Geez, does one extra snack really affect the bottom line??
Air Canada
7.1
Good
10,000 reviews
United Airlines
7.4
Good
8,937 reviews

Overall

7.4

Entertainment

7.1

Comfort

7.3

Crew

8.1

Food

6.6

Boarding

7.7

Reviews

1 / 20
4.0
Okay

Thomas,Mar 2025

SFO - TPE

When I asked for an extra snack, I got an unhappy look from the stewardess. Geez, does one extra snack really affect the bottom line??
Iberia
7.0
Good
2,929 reviews
United Airlines
7.4
Good
8,937 reviews

Overall

7.4

Entertainment

7.1

Comfort

7.3

Crew

8.1

Food

6.6

Boarding

7.7

Reviews

1 / 20
4.0
Okay

Thomas,Mar 2025

SFO - TPE

When I asked for an extra snack, I got an unhappy look from the stewardess. Geez, does one extra snack really affect the bottom line??
British Airways
6.7
Okay
7,361 reviews
United Airlines
7.4
Good
8,937 reviews

Overall

7.4

Entertainment

7.1

Comfort

7.3

Crew

8.1

Food

6.6

Boarding

7.7

Reviews

1 / 20
4.0
Okay

Thomas,Mar 2025

SFO - TPE

When I asked for an extra snack, I got an unhappy look from the stewardess. Geez, does one extra snack really affect the bottom line??

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 0 outbound flights to London per day. You should also have plenty of airline options to choose from since 10 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 10h 32m. United Airlines provides one of the quickest options available for as low as $528. St. Louis and London are separated by a distance of 4186 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    According to our current data, KLM ($530), Delta ($631), and British Airways ($631) offers the cheapest pricing from St. Louis to London. These flights start at 43% lower than the current average price 3 months from now.

  • 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 City.

  • 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, November is the cheapest month in which you can book a flight from St. Louis to London (average of $661). Flying from St. Louis to London in June is currently the most expensive (average of $1,098). 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
Hounslow
Hayes
Thornton Heath
Southend-on-Sea
Harrow
Canterbury
Croydon
Eastleigh
Dartford
Dover
Winchester
Orpington
Gatwick
Borehamwood
Aylesbury
Bedford
Wembley
Folkestone
Chichester
Arundel

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Alternative routes for St. Louis to London

See prices for flight routes from nearby airports that may be better suited for you.
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Top 10 airlines flying from St. Louis to London

Discover the top 10 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 September 11, 2025.
AirlineCheapestAverageFlexibilityOn-time
KLMCheapest$530Average$736FlexibilityNo cancel feeOn-time75%
DeltaCheapest$631Average$960FlexibilityNo cancel feeOn-timeN/A
British AirwaysCheapest$631Average$945FlexibilityNo cancel feeOn-time70%
American AirlinesCheapest$638Average$910FlexibilityNo cancel feeOn-time71%
Scandinavian AirlinesCheapest$669Average$1,102FlexibilityNo cancel feeOn-time77%
United AirlinesCheapest$669Average$920FlexibilityNo cancel feeOn-time69%
LufthansaCheapest$670Average$888FlexibilityNo cancel feeOn-time76%
IberiaCheapest$671Average$985FlexibilityNo cancel feeOn-time77%
Air CanadaCheapest$691Average$955FlexibilityNo cancel feeOn-time67%
Virgin AtlanticCheapest$727Average$913FlexibilityNo cancel feeOn-time72%

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