Cheap flights from London Heathrow Airport to St. Louis from £356

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 27/2. Fares are subject to change and may not be available on all flights or dates of travel.
LHR — STL
12 Dec — 19 Dec1
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 25 days in advance, depart on a Saturday or Monday and return on a Tuesday

Cheap 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 12 November 2025.

Round-trip from

£531

One-way from

£356

Popular in

August

Cheapest in

February

Average price

£732

Good round-trip deal

£465 or less
KLM
  • KLM
  • 8/12-15/12
  • 3 total stops
  • 27h 43m total
  • London to St. Louis
27/2
  • 27/2
  • 2 total stops
  • 48h 57m total
  • London to St. Louis
Highest demand for flights based on searches. 6% potential increase in price (£37 potential increase over avg. return price).
Cheapest flight prices on average. 1% potential price decrease (£10 potential savings vs. average return price).
Average for round-trip flights in November 2025
Price to beat on a round-trip flight from London Heathrow to Lambert-St Louis.

Find 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 12 November 2025.

Mon 8/1206:30LHR - STL
2 stops15h 36mKLM
Mon 15/1214:38STL - LHR
1 stop12h 07mKLM
Deal found 10/11£531
Tue 9/1211:55LHR - STL
1 stop13h 34mFinnair
Tue 16/1206:00STL - LHR
1 stop19h 50mFinnair
Deal found 11/11£533
Mon 8/1206:30LHR - STL
2 stops15h 36mVirgin Atlantic
Mon 15/1210:45STL - LHR
2 stops14h 05mVirgin Atlantic
Deal found 10/11£547
Tue 9/1206:30LHR - STL
2 stops18h 03mDelta
Tue 16/1210:45STL - LHR
2 stops13h 40mDelta
Deal found 11/11£549
Mon 8/1206:30LHR - STL
2 stops16h 19mDelta
Mon 15/1214:38STL - LHR
2 stops15h 02mDelta
Deal found 10/11£549
Wed 10/1210:00LHR - STL
2 stops16h 47mVirgin Atlantic
Wed 17/1214:02STL - LHR
1 stop10h 23mVirgin Atlantic
Deal found 11/11£568
Mon 24/1106:30LHR - STL
2 stops18h 05mVirgin Atlantic
Mon 1/1211:39STL - LHR
1 stop12h 46mVirgin Atlantic
Deal found 10/11£568
Mon 24/1108:20LHR - STL
1 stop14h 07mBritish Airways
Mon 1/1214:17STL - LHR
1 stop11h 58mBritish Airways
Deal found 10/11£570
Wed 10/1208:20LHR - STL
1 stop14h 14mBritish Airways
Wed 17/1214:48STL - LHR
1 stop10h 12mBritish Airways
Deal found 11/11£572
Mon 24/1115:35LHR - STL
2 stops23h 45mFinnair
Sun 30/1118:45STL - LHR
1 stop32h 30mFinnair
Deal found 10/11£576
Wed 10/1215:50LHR - STL
1 stop27h 26mDelta
Wed 17/1214:02STL - LHR
1 stop10h 23mDelta
Deal found 11/11£581

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 12 November 2025.
Use the filters below to find and compare flights from London Heathrow Airport to St. Louis that are best for you.

Fly from

Heathrow

Fly to

St. Louis

Route

Depart

Return

Price

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Wed 22/4

09:15-17:13

1 stop13h 58m

Lambert-St Louis

Wed 6/5

18:29-12:15

1 stop11h 46m

£543

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Tue 9/12

06:30-18:33

2 stops18h 03m

Lambert-St Louis

Tue 16/12

10:45-06:25

2 stops13h 40m

£549

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Mon 8/12

06:30-16:49

2 stops16h 19m

Lambert-St Louis

Mon 15/12

14:38-11:40

2 stops15h 02m

£549

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Wed 22/4

16:25-19:30

Nonstop9h 05m

Lambert-St Louis

Wed 6/5

22:00-12:05

Nonstop8h 05m

£557

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Wed 7/1

12:40-23:25

2 stops16h 45m

Lambert-St Louis

Wed 14/1

09:59-08:05

2 stops16h 06m

£565

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Wed 10/12

10:00-20:47

2 stops16h 47m

Lambert-St Louis

Wed 17/12

14:02-06:25

1 stop10h 23m

£568

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Wed 10/12

06:30-17:10

2 stops16h 40m

Lambert-St Louis

Wed 17/12

14:02-06:25

1 stop10h 23m

£568

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Tue 13/1

15:35-09:03

2 stops23h 28m

Lambert-St Louis

Fri 23/1

15:37-10:00

1 stop12h 23m

£569

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Tue 5/5

06:50-15:16

2 stops14h 26m

£357

LondonSt. Louis

LHR - STL

LHRSTL

London Heathrow

Tue 5/5

16:25-19:30

Nonstop9h 05m

£362

Flights are sorted by cheapest return flights first.

Deals found on 10/11

Showing 1-10 of 17 results
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 7 November 2025.

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 25 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 £412). Flying from London Heathrow Airport to St. Louis in July is currently the most expensive (average of £628). 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 LHR to STL?

Find hourly flight availability from Heathrow to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated 12 November 2025.

A simple way to save on the total cost of your ticket is to fly from London Heathrow Airport to St. Louis in the evening. If you’re flexible enough to do this you can expect to save up to 18% on your trip compared to booking a flight in the afternoon.

What is the cheapest day to fly from London Heathrow Airport to St. Louis?

Use this chart to determine the cheapest time to fly return from Heathrow to St. Louis. Price data was last updated on 16 December 2024.

Travellers seeking maximum savings on their London Heathrow Airport to St. Louis flight should consider departing on Sunday afternoons when fares are most often at their lowest. Saturday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

How much does it cost for a return flight from London Heathrow Airport to St. Louis?

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 12 November 2025.
Get a feel of what it's like to fly with Finnair, United Airlines, andIberia 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.

Crew

8.1

Food

6.7

Overall

7.6

Comfort

7.4

Entertainment

6.9

Boarding

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.

Crew

8.1

Food

6.7

Overall

7.6

Comfort

7.4

Entertainment

6.9

Boarding

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.

Crew

8.1

Food

6.7

Overall

7.6

Comfort

7.4

Entertainment

6.9

Boarding

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.

Crew

8.1

Food

6.7

Overall

7.6

Comfort

7.4

Entertainment

6.9

Boarding

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.

Crew

8.1

Food

6.7

Overall

7.6

Comfort

7.4

Entertainment

6.9

Boarding

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.

Crew

8.1

Food

6.7

Overall

7.6

Comfort

7.4

Entertainment

6.9

Boarding

7.6

Reviews

1 / 20
10.0
Excellent

Anonymous,May 2025

FRA - DFW

I was lucky I had a seet without no one next to me My vegetarian meal was excellent. The service very good. Although there was a lot of turbulences during the flight, the landing was very soft and took away all our apprehension.

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. 10 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 9h 05m. 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 £89. Other airlines that can offer you cheap pricing are Scandinavian Airlines, from £489, and KLM, from £513. American Airlines is priced at 88% lower than the current average price of a flight leaving 3 months from now.

  • 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 £682, our data shows the cheapest flight currently is £463. When looking at the most popular route, (London Heathrow - Lambert-St Louis), you can expect to pay £523 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 £412). Flying from London Heathrow Airport to St. Louis in July is currently the most expensive (average of £628). 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

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Top 10 airlines flying from Heathrow to St. Louis

Discover the top 10 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 12 November 2025.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest£89Average£781FlexibilityNo cancel feeOn-time71%
Search American Airlines flights
Scandinavian AirlinesCheapest£489Average£632FlexibilityNo cancel feeOn-time77%
Search Scandinavian Airlines flights
KLMCheapest£513Average£858FlexibilityNo cancel feeOn-time75%
Search KLM flights
FinnairCheapest£519Average£670FlexibilityNo cancel feeOn-time76%
Search Finnair flights
Air CanadaCheapest£616Average£768FlexibilityNo cancel feeOn-time67%
Search Air Canada flights
British AirwaysCheapest£619Average£826FlexibilityNo cancel feeOn-time70%
Search British Airways flights
United AirlinesCheapest£637Average£775FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
IberiaCheapest£638Average£734FlexibilityNo cancel feeOn-time77%
Search Iberia flights
LufthansaCheapest£706Average£825FlexibilityNo cancel feeOn-time76%
Search Lufthansa flights
Virgin AtlanticCheapest£708Average£868FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic 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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