Cheap flights from London Heathrow Airport to St. Louis from £289

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 29/4. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — STL
6 Apr — 13 Apr1
1 adult
1 adult, Economy, 0 bags
Cheapflights Tip: The best prices from London Heathrow to Lambert-St Louis are usually found in February or March, booked 72 days in advance, depart on a Thursday or Friday and return on a Monday

Cheap flight deals from Heathrow to St. Louis

Enter your travel dates to find the best prices.

Cheapest flights from Heathrow to St. Louis
Explore the most affordable flight options available from Heathrow to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on 7 March 2026.

Wed 2/916:25
LHR
-
STL
Nonstop9h 05m
British Airways
Wed 23/912:47
STL
-
LHR
1 stop12h 08m
British Airways
Deal found 4/3£526
Tue 21/412:30
LHR
-
STL
1 stop12h 59m
British Airways
Wed 29/421:35
STL
-
LHR
Nonstop8h 00m
British Airways
Deal found 5/3£530
Wed 13/516:25
LHR
-
STL
Nonstop9h 05m
Finnair
Thu 21/505:15
STL
-
LHR
1 stop22h 10m
Finnair
Deal found 4/3£536
Mon 13/412:15
LHR
-
STL
1 stop16h 02m
Finnair
Tue 21/412:27
STL
-
LHR
1 stop17h 43m
Finnair
Deal found 4/3£540
Tue 21/418:05
LHR
-
STL
2 stops29h 07m
Finnair
Wed 29/414:12
STL
-
LHR
1 stop12h 53m
Finnair
Deal found 5/3£541
Wed 2/910:05
LHR
-
STL
2 stops16h 14m
Finnair
Wed 23/909:32
STL
-
LHR
1 stop15h 23m
Finnair
Deal found 3/3£542
Wed 20/509:20
LHR
-
STL
1 stop12h 50m
Delta
Thu 28/510:15
STL
-
LHR
1 stop14h 55m
Delta
Deal found 4/3£544
Tue 14/409:45
LHR
-
STL
1 stop12h 15m
American Airlines
Thu 23/417:21
STL
-
LHR
1 stop11h 09m
American Airlines
Deal found 4/3£545
Wed 23/906:45
LHR
-
STL
2 stops22h 53m
British Airways
Sun 27/920:07
STL
-
LHR
1 stop28h 43m
British Airways
Deal found 3/3£552

Find flight deals from Heathrow to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Heathrow (LHR) to St. Louis (STL). 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 7 March 2026.

Round-trip from

£526

One-way from

£289

Popular in

July

Cheapest in

February

Average price

£703

Good round-trip deal

£567 or less
British Airways
  • British Airways
  • 2/9-23/9
  • 1 total stop
  • 21h 13m total
  • London to St. Louis
29/4
  • 29/4
  • 3 total stops
  • 39h 26m total
  • London to St. Louis
Highest demand for flights based on searches. 7% potential increase in price (£45 potential increase over avg. return price).
Cheapest flight prices on average. 1% potential price decrease (£8 potential savings vs. average return price).
Average for round-trip flights in March 2026
Price to beat on a round-trip flight from London Heathrow to Lambert-St Louis.

Cheapflights Fare Finder

 
Customise your flight search to find flights from Heathrow to St. Louis 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 858,174 searches. Data last updated 7 March 2026.
Use the filters below to find and compare flights from London Heathrow Airport to St. Louis that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Thu 30/4

21:50-19:29

2 stops27h 39m

Lambert-St Louis

Thu 7/5

11:45-08:00

1 stop14h 15m

£578

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Fri 24/4

06:15-16:42

2 stops16h 27m

Lambert-St Louis

Fri 8/5

19:01-14:35

2 stops13h 34m

£630

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Fri 24/4

16:25-19:30

Nonstop9h 05m

Lambert-St Louis

Fri 8/5

06:00-06:20

1 stop18h 20m

£632

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Thu 30/4

11:45-23:36

2 stops17h 51m

Lambert-St Louis

Sun 31/5

16:20-14:35

1 stop16h 15m

£658

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Thu 16/4

10:45-16:42

1 stop11h 57m

Lambert-St Louis

Sat 18/4

17:59-07:10

1 stop31h 11m

£666

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Tue 19/5

11:30-21:09

2 stops15h 39m

Lambert-St Louis

Thu 28/5

13:56-09:15

2 stops13h 19m

£693
Fastest return journey

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Tue 19/5

16:25-19:30

Nonstop9h 05m

Lambert-St Louis

Thu 28/5

13:45-09:05

1 stop13h 20m

£704

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Tue 19/5

06:30-17:05

2 stops16h 35m

Lambert-St Louis

Thu 28/5

10:49-07:10

2 stops14h 21m

£712

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Wed 1/7

06:30-16:55

2 stops16h 25m

Lambert-St Louis

Wed 15/7

19:05-14:35

2 stops13h 30m

£712

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Thu 30/4

06:40-23:36

3 stops22h 56m

Lambert-St Louis

Thu 7/5

10:49-16:00

2 stops23h 11m

£732

Flights are sorted by cheapest return flights first.

Deals found on 3/3

Showing 1-10 of 20 resultsSorted by cheapest first
1
2

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

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Heathrow with our price prediction graph.
Estimated return 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 London Heathrow Airport to St. Louis

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

Use this chart to determine the optimal time to book a return flight from Heathrow to St. Louis. Price data was last updated on 6 March 2026.

To ensure you get the cheapest price possible for a flight from London Heathrow Airport to St. Louis, you should look to book at least 72 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

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

Currently, September is the cheapest month in which you can book a flight from London Heathrow Airport to St. Louis (average of £407). Flying from London Heathrow Airport to St. Louis in December is currently the most expensive (average of £625). 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.

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. 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 St. Louis. Reviews last updated 7 March 2026.
Get a feel of what it's like to fly with Finnair, United Airlines, andAir Canada from London Heathrow Airport to St. Louis by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.

Overall

7.6

Boarding

7.7

Crew

8.2

Comfort

7.5

Entertainment

6.9

Food

6.7

Reviews

1 / 20
2.0
Mediocre

Vlad-Valentin,Jan 2026

LHR - YVR

baggage allowance was different between the outgoing and inbound flights

Overall

7.6

Boarding

7.7

Crew

8.2

Comfort

7.5

Entertainment

6.9

Food

6.7

Reviews

1 / 20
2.0
Mediocre

Vlad-Valentin,Jan 2026

LHR - YVR

baggage allowance was different between the outgoing and inbound flights

Overall

7.6

Boarding

7.7

Crew

8.2

Comfort

7.5

Entertainment

6.9

Food

6.7

Reviews

1 / 20
2.0
Mediocre

Vlad-Valentin,Jan 2026

LHR - YVR

baggage allowance was different between the outgoing and inbound flights

Overall

7.6

Boarding

7.7

Crew

8.2

Comfort

7.5

Entertainment

6.9

Food

6.7

Reviews

1 / 20
2.0
Mediocre

Vlad-Valentin,Jan 2026

LHR - YVR

baggage allowance was different between the outgoing and inbound flights

Overall

7.6

Boarding

7.7

Crew

8.2

Comfort

7.5

Entertainment

6.9

Food

6.7

Reviews

1 / 20
2.0
Mediocre

Vlad-Valentin,Jan 2026

LHR - YVR

baggage allowance was different between the outgoing and inbound flights

Overall

7.6

Boarding

7.7

Crew

8.2

Comfort

7.5

Entertainment

6.9

Food

6.7

Reviews

1 / 20
2.0
Mediocre

Vlad-Valentin,Jan 2026

LHR - YVR

baggage allowance was different between the outgoing and inbound flights

Related info for your journey

Find useful and relevant information for your journey from Heathrow to St. Louis. 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 into for flights to St. Louis from London Heathrow?

    For a flight from London Heathrow to St. Louis, you will be flying into Lambert-St Louis. Lambert-St Louis (STL) is just 12.7 mi from the center of the city. Lambert-St Louis is the only St. Louis airport and it handles 0 inbound flights from London Heathrow per day. 9 airlines have flights to Lambert-St Louis from London Heathrow on a regular basis.

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

    Departing from London Heathrow Airport to St. Louis will take you 16h 27m. London Heathrow Airport and St. Louis are separated by a distance of 4186 mi. This flight may include one or multiple stops.

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

    Cheapflights users have booked flights from London Heathrow Airport to St. Louis round-trip from £171. Other airlines that can offer you cheap pricing are United Airlines, from £474, and British Airways, from £480. American Airlines is priced at 76% lower than the current average price of a flight leaving 3 months from now.

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

    For one-way options, check prices for British Airways. According to our data, you can fly for as low as £344. Users have also found prices from £359 and £363 on United Airlines and Finnair, respectively.

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

    While on average a flight from London Heathrow Airport to St. Louis is generally £705, our data shows the cheapest flight currently is £543. When looking at the most popular route, (London Heathrow - Lambert-St Louis), you can expect to pay £526 for that flight.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from Heathrow to St. Louis 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 London Heathrow Airport to St. Louis?

    Currently, September is the cheapest month in which you can book a flight from London Heathrow Airport to St. Louis (average of £407). Flying from London Heathrow Airport to St. Louis in December is currently the most expensive (average of £625). 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

Browse thousands of different options on Cheapflights for your next trip

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Top 9 airlines flying from Heathrow to St. Louis

Discover the top 9 airlines that operate flights from Heathrow to St. Louis. 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 858,174 searches. Data last updated 7 March 2026.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest£171Average£769FlexibilityNo cancel feeOn-time71%
Search American Airlines flights
United AirlinesCheapest£474Average£741FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
British AirwaysCheapest£480Average£754FlexibilityNo cancel feeOn-time70%
Search British Airways flights
KLMCheapest£521Average£803FlexibilityNo cancel feeOn-time75%
Search KLM flights
FinnairCheapest£551Average£674FlexibilityNo cancel feeOn-time76%
Search Finnair flights
Virgin AtlanticCheapest£557Average£781FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
Air CanadaCheapest£605Average£744FlexibilityNo cancel feeOn-time67%
Search Air Canada flights
IberiaCheapest£659Average£731FlexibilityNo cancel feeOn-time77%
Search Iberia flights
LufthansaCheapest£662Average£804FlexibilityNo cancel feeOn-time76%
Search Lufthansa flights

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from Heathrow to St. Louis?

Cheapflights makes it easy to find Heathrow to St. Louis flights by helping our users search from 900+ travel sites for deals. We also provide you with filters for cabin, price, airline, airports, number of stops, and many more to narrow down that perfect flight.

Why should you use Cheapflights to find cheap flight tickets from Heathrow to St. Louis?

By finding flights from multiple airlines and providers at completely no cost, Cheapflights helps millions of users like you annually find the best flights to St. Louis from Heathrow.

Can Cheapflights find flights from Heathrow to St. Louis with no change fees?

Certainly. Search results for flights to St. Louis from Heathrow shown to you on Cheapflights can be narrowed down with different useful search filters, which includes flexible booking options.

Can Cheapflights notify me if prices for flights from Heathrow to St. Louis become cheaper?

Yes, Cheapflights offers price alerts on Heathrow to St. Louis flights so you can book your travel at the perfect time. Price Alerts can be enabled by clicking the bell icon next to the flight deals above and providing your email address where you want to receive the alerts.

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