STL - LHR

£238 Find Cheap Flights from St. Louis to London Heathrow Airport

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from St. Louis to Heathrow departing on 14/9. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy

KAYAK searches hundreds of travel sites at once for deals on flights to London Heathrow Airport

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to London, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to London, as well as popular online travel agencies
Travellers love KAYAK
41,299,237 searches in the past 7 days on KAYAK

Save 26% or moreCompare multiple travel sites with one search.

Track pricesNot ready to book? Create a price alert for when prices drop.

Bundle and saveSave money when you bundle your flight + hotel.

Filter your dealsChoose cabin class, free Wi-Fi and more.

Flights Deals
Booking Insights
Flights Deals

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

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for return flights from St. Louis to Heathrow that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent return flight deals from St. Louis to Heathrow

Sun, 14 Sep - Tue, 30 Sep
Air Canada Logo
13:30 - 09:35STL-LHR
14h 05m1 stop
Air Canada Logo
06:50 - 15:18LHR-STL
14h 28m2 stops
£360Air Canada
Find Deal
Sun, 14 Sep - Tue, 30 Sep
Air Canada Logo
13:30 - 09:35STL-LHR
14h 05m1 stop
Air Canada Logo
12:05 - 19:38LHR-STL
13h 33m1 stop
£370Air Canada
Find Deal
Tue, 23 Sep - Tue, 30 Sep
 Logo
09:15 - 06:30STL-LHR
15h 15m2 stops
 Logo
06:50 - 15:18LHR-STL
14h 28m2 stops
Tue, 14 Oct - Wed, 22 Oct
United Airlines Logo
13:30 - 06:30STL-LHR
11h 00m1 stop
United Airlines Logo
14:05 - 10:49LHR-STL
26h 44m2 stops
£380United Airlines
Find Deal
Tue, 19 Aug - Wed, 27 Aug
 Logo
13:30 - 10:15STL-LHR
14h 45m2 stops
 Logo
06:50 - 20:00LHR-STL
19h 10m2 stops
Mon, 3 Nov - Tue, 11 Nov
United Airlines Logo
11:20 - 10:15STL-LHR
16h 55m1 stop
United Airlines Logo
13:25 - 14:25LHR-STL
31h 00m2 stops
£383United Airlines
Find Deal
Mon, 18 Aug - Wed, 27 Aug
British Airways Logo
17:52 - 12:45STL-LHR
12h 53m1 stop
British Airways Logo
19:30 - 19:09LHR-STL
29h 39m2 stops
£390British Airways
Find Deal
Mon, 18 Aug - Wed, 27 Aug
British Airways Logo
19:59 - 12:15STL-LHR
10h 16m1 stop
British Airways Logo
12:15 - 18:23LHR-STL
12h 08m1 stop
£393British Airways
Find Deal
Tue, 2 Sep - Fri, 12 Sep
Virgin Atlantic Logo
10:20 - 06:20STL-LHR
14h 00m2 stops
Virgin Atlantic Logo
11:45 - 23:09LHR-STL
17h 24m2 stops
£404Virgin Atlantic
Find Deal
Wed, 20 Aug - Thu, 4 Sep
Virgin Atlantic Logo
10:45 - 06:45STL-LHR
14h 00m2 stops
Virgin Atlantic Logo
10:55 - 22:02LHR-STL
17h 07m2 stops
£405Virgin Atlantic
Find Deal
Booking Insights

KAYAK's insights & trends for St. Louis to Heathrow flights

Get data-powered insights and trends into flights from St. Louis to Heathrow to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from St. Louis to London Heathrow Airport?

What’s the cheapest day of the week to fly from St. Louis to London Heathrow Airport?

The average price of all round-trip flights from St. Louis to London Heathrow Airport clicked on KAYAK for each day over the last 12 months.

If your flying dates are flexible, you should consider flying to London Heathrow Airport on a Tuesday, as we generally find the cheapest rates on that day for this route. On the other hand, Friday is the most expensive day to fly from St. Louis to London Heathrow Airport. For your return ticket, we recommend flying on a Wednesday and avoiding Thursdays for the best deals.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from St. Louis to London Heathrow Airport, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from St. Louis to London Heathrow Airport is October, where tickets cost £610 (return) on average. On the other hand, the most expensive months are June and December, where the average cost of round-trip tickets is £962 and £886 respectively.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from St. Louis to London Heathrow Airport, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from St. Louis to London Heathrow Airport, you should book around 3 weeks before departure, which saves you about 33% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 9 weeks before departure.


Good to know - Cheap tickets from St. Louis to London Heathrow Airport

Low seasonFebruary
Cheapest flight£238
Best time to beat the crowds (4% less expensive on average)
Most popular time to fly (5% more expensive on average)
Flight from St. Louis to London Heathrow Airport

When to book flights from St. Louis to Heathrow

Are your dates flexible? Find out the best times to travel from St. Louis to Heathrow based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated return price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or returns with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking St. Louis to London Heathrow Airport flights

  • What is the cheapest flight from St. Louis to London Heathrow Airport?

    In the last 3 days, the lowest price for a flight from St. Louis to London Heathrow Airport was £315 for a one-way ticket and £476 for a return.

  • Which airports will I be using when flying from St. Louis to London Heathrow Airport?

    On your way to London Heathrow Airport, you’ll fly out from Lambert-St Louis. You’ll be landing at London Heathrow.

  • Which aircraft models fly most regularly from St. Louis to London Heathrow Airport?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from St. Louis to London Heathrow Airport?

    Star Alliance, oneworld, and SkyTeam are the airline alliances operating flights between St. Louis and London Heathrow Airport, with SkyTeam being the most commonly used for this route.

  • Which is the best airline for flights from St. Louis to London, KLM or Virgin Atlantic?

    The two airlines most popular with KAYAK users for flights from St. Louis to London are KLM and Virgin Atlantic. With an average price for the route of £810 and an overall rating of 7.8, KLM is the most popular choice. Virgin Atlantic is also a great choice for the route, with an average price of £813 and an overall rating of 7.4.

  • How does KAYAK find such low prices on flights from St. Louis to London Heathrow Airport?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from St. Louis to London Heathrow Airport.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from St. Louis to London Heathrow Airport?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to London Heathrow Airport from St. Louis is likely to change within 7 days, so travellers know whether to wait or book now.

  • What is the Hacker Fare option on flights from St. Louis to London Heathrow Airport?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional return ticket. You could then fly to London Heathrow Airport with an airline and back to St. Louis with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from St. Louis to London Heathrow Airport?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to London Heathrow Airport from St. Louis up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top 4 airlines flying from St. Louis to Heathrow

 
See real verified KAYAK customer reviews for airlines flying from St. Louis to London. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from St. Louis to Heathrow? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.8
KLMOverall score based on 1384 reviews
7.1Entertainment
7.7Comfort
7.8Boarding
8.4Crew
7.3Food
Airline reviews

Our first flight was delayed so we missed our connecting flight. However it was easy to book a later flight on their app.

6.0 GoodKathleen P, Jun 2025EDI - AMS
Read more KLM reviews

Our first flight was delayed so we missed our connecting flight. However it was easy to book a later flight on their app.

My flight was delayed by 6 hours then I missed BOTH of my connecting flights, I then had to stay in the AIRPORT at JFK because soooooo many people also suffered from missing flights and there was no hotels available. I would like to be compensated for this experience! I had to stay in the airport for over 16 hours!

Klm start boarding while somw air issue in the plan

I appreciate that KLM was proactive in informing me of the 2 hour delay which enabled me to replan my travel. It was a bit stressful not knowing whether my connection from Montreal to Ottawa was happening. But the ground and air crew did a good job at comforting and assuring me.

Cabin crew professional, polite and friendly, boarding was seemless, but come on KLM surely you can do better than a pack of cheesy biscuits as an inflight snack

Cabin crew were excellent, very proffesional, polite and friendly, in flight snack was underwhelming, a packet of cheese biscuits, im sure KLM could run to a sandwich!

Legroom not all it could be, especially when the seat in front is reclined. Otherwise it was good, food and beverage were nice.

You should not have to pay for WiFi in business class

Transfer at Amsterdam airport is very convenient and the airport is easy to navigate. Boarding was also quick and easy. Cabin crew were excellent and the meals were good, although lacking in options.

Overall very positive. Boarding was quick and organized. Cabin was clean and seats were reasonably comfortable. Cabin crew was excellent and the meals provided were also of good quality

Great crew - old style upper class seats on the older fleet now feels dated

Premium economy more comfortable than economy, but not by much. Did was awful, do not try the omelette. Flight crew were helpful. Flight was delayed by over an hour. Overall but bad, arrived safely and thank God.

Food was excellent. Service was very good. Staff was very helpful to all passengers.

The crew was excellent as ever on Virgin. The special meal was poor unfortunately. More significantly when we arrived at Manchester Airport there was no air bridge provided and we had to exit the plane down a rickety stair case. This is unacceptable for a transatlantic flight. Whilst I understand that this is the airport’s fault at the end of the day the airline is responsible for our transportation and needs to do something.

Super friendly and helpful staff, from check-in desk to cabin crew.

Following a paid seat upgrade for enhanced comfort, I encountered an unacceptable odor in my assigned area. It took three hours for the crew to relocate me, and the replacement seat was unacceptably close to the lavatory, offering no improvement.

Good overall. Cannot fault the airlines. I have had better entertainment systems before ie ice in Emirates but it was not too bad. Food was decent and staff were friendly.

I did not fly by vergin atlantic from bangalore to vasco da gama

Your flight delayed at Heathrow n I almost missed my mother funeral.you idiots. I had to waste 10 hours in different airports. Thank your stars I'm not suing you.

Miami airport needs more thorough signage. It was a long walk from my transport point to the check in desk,

Both flights are delayed so I rate the whole experience as mediocre.

I booked my flight months ago, and checked-in online about 12 hours before the flight. I received an email confirmation of check-in. I had no subsequent communication from Air Canada after my original booking. After arriving at the airport three hours before the flight, as instructed, I waited 90 minutes for an agent to appear to check my bag. I was informed that my flight had been canceled many weeks before, and that flight was no longer being run!! I showed a copy of my check-in confirmation, but no explanation could be found. I was placed on standby for the next flight and the connection. Luckily, those flights were not full and I arrived at my destination. I double checked my email, but I received no update about the flight from Air Canada until the day of the flight.

I had a good experience. I liked being informed about the status of my luggage

Very bad service the way back we was on the way for r two days very bad condition and waiting for luggage till now

I was forcefully re-routed to another destination and was delayed a total of 8hours. I have still not received my bags, no one is taking responsibility. The agents at the airport lied to me that I will get to my destination same time as my previous flight where I was forcefully re-routed from.

In flight entertainment system did not work across the whole plane for entire flight. Seats were very cramped. Cabin temperature was freezing cold. Crew was miserable and answered everyone in a short and barking manner. I’ve flown air Canada many many times and never had an issue. But this was unpleasant.

Flight was delayed by 1.5hrs. Once inside, people had their small handbags on the storage. The crew (male guy) was not helpful in making some space in the storage. Instead, he asked few bags to be checked-in and it was not a great experience. No attempt to help but just followed the things with a straight face. People had their literally small bags and he wouldnt not move from one storage to another even if there was space and would not let us do i as well. Once flight was on, they ran out of Orange juice, really running out of orange juice when the temp were 32.degrees outside. didnt made the sense. Onasking for a extra snack, he made a face as if he was giving me out of his pocket. if the flight was delayed, there could have an attempt to provide something extra incase people did asked.

Our flight was canceled at the last minute. Someone on the flight said the exact same thing happened to her the day before. I will say they helped us book a flight on another airline so that we could still make our vacation with little delay.

United had no (zero) record of our flight. It took over an hour of us standing in line with surly employee while others waited to get resolved. I have never experienced such poor service and poor empathy.

They screwed up so bad, I asked for a short check for my luggage since we had a 21 hour overnight layover in London at a hotel. They said I have to receive my luggage in London because it’s an overnight layover. Get to London, nope, my bags aren’t coming off they are staying in terminal 5 over night and going straight to Ibiza. So we had no luggage for a whole day and basically stuck with no clothes or washroom stuff. Finally get to Ibiza and my luggage is completely smashed and damaged and missing a wheel. Now I have to drag this 50 lbs luggage around Ibiza islands for 10 days. Wtf. So pissed off Air Canada is LITERALLY THE WORST AIRLINE IN THE WORLD

Flight was delayed. Though I checked in with BA live chat three times, our special meals were not provided.

My experience with British Airways is excellent, thanks for all 🫶🏻✈️

The crew is very friendly and helpful. The food is good for airplane food. The flight is long and hard to sleep. The leg space is great. The plane arrived in plenty of time.

Enjoyable flight, helpful crew everything was organized to accommodate passengers.

Captain sick. Unable to get replacement so delayed me 30 hours, many others delayed 54 hours. TOTALLY DESTROYED ALL MY PLANS, including lost my rental car which would now cost over 5 times what I paid so stuck with buses n trains... lost hotel reservations.... HORRIBLE!!!

They’ve lost my bag and I have no way of really getting in touch with anyone and have received no updates.

Very crowded, no real explanation of food "chicken or pasta?" After dinner no drinks service. Plane was clean, but little help with finding soaces fir luggage to get into overhead bins. Many passengers putting 2 bags, hats, duty free in overhead bins so no space for roll ons

Flight was good but seat in 12D was not comfortable, better on the Airbus 321 from Tampa to Charlotte. No breakfast was served before landing in zLonfon only a coffee and orange juice.

I was transferred to an American Airlines flight. The boarding was late and unorganized. The seating was extremely tight and uncomfortable. Will not use AA again.

The entertainment selection was ok, but overall not bad! The crew was great.

Everything you need to know for your flight from St. Louis to Heathrow

Information on your arrival and departure airports

Not what you’re looking for? Find thousands of other hotels, flights, car hires and package deals with KAYAK.