STL - LHR

£459 Find Cheap Flights from St. Louis to London Heathrow Airport

This is the cheapest return flight price found by a KAYAK user in the last 72 hours by searching for a flight from St. Louis to Heathrow departing on 19/8. 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
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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

Tue, 19 Aug - Wed, 27 Aug
United Airlines Logo
13:30 - 10:00STL-LHR
14h 30m1 stop
United Airlines Logo
06:30 - 13:30LHR-STL
13h 00m1 stop
£459United Airlines
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Tue, 19 Aug - Thu, 28 Aug
British Airways Logo
16:19 - 09:05STL-LHR
10h 46m1 stop
British Airways Logo
14:25 - 20:18LHR-STL
11h 53m1 stop
£460British Airways
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Sun, 21 Sep - Wed, 1 Oct
Iberia Logo
16:02 - 10:50STL-LHR
12h 48m1 stop
Iberia Logo
06:15 - 21:53LHR-STL
21h 38m2 stops
£464Iberia
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Tue, 19 Aug - Thu, 28 Aug
Air Canada Logo
13:30 - 06:30STL-LHR
11h 00m1 stop
Air Canada Logo
06:50 - 15:21LHR-STL
14h 31m2 stops
£465Air Canada
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Sun, 21 Sep - Wed, 1 Oct
Air Canada Logo
13:30 - 09:35STL-LHR
14h 05m1 stop
Air Canada Logo
14:05 - 19:57LHR-STL
11h 52m1 stop
£469Air Canada
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Tue, 9 Sep - Tue, 23 Sep
Iberia Logo
09:56 - 07:20STL-LHR
15h 24m1 stop
Iberia Logo
14:25 - 20:32LHR-STL
12h 07m1 stop
£475Iberia
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Tue, 8 Jul - Tue, 29 Jul
KLM Logo
10:46 - 06:45STL-LHR
13h 59m1 stop
KLM Logo
12:25 - 23:20LHR-STL
16h 55m1 stop
£523KLM
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Tue, 15 Jul - Tue, 22 Jul
KLM Logo
10:46 - 06:45STL-LHR
13h 59m1 stop
KLM Logo
11:45 - 20:36LHR-STL
14h 51m1 stop
£524KLM
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Tue, 8 Jul - Tue, 29 Jul
Virgin Atlantic Logo
10:46 - 06:45STL-LHR
13h 59m2 stops
Virgin Atlantic Logo
12:25 - 23:20LHR-STL
16h 55m1 stop
£527Virgin Atlantic
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Mon, 21 Jul - Wed, 6 Aug
Virgin Atlantic Logo
15:41 - 11:25STL-LHR
13h 44m2 stops
Virgin Atlantic Logo
10:55 - 20:36LHR-STL
15h 41m2 stops
£542Virgin Atlantic
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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.

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 £594 (return) on average. On the other hand, the most expensive months are June and December, where the average cost of round-trip tickets is £945 and £849 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 4 weeks before departure. 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
High seasonMay
Cheapest flight£232
Best time to beat the crowds (0% less expensive on average)
Most popular time to fly (3% 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 £624 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?

    oneworld, Star Alliance, 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 £789 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 £804 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.

Top 5 airlines serving 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 1358 reviews
7.2Food
7.1Entertainment
7.8Boarding
7.7Comfort
8.4Crew
Airline reviews

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.

8.0 ExcellentShereen, Apr 2025AMS - YUL
Read more KLM reviews

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.

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

This fight left ahead of time which meant it arrived early which was great. Staff were very professional, but as with all these Short hop Flights the food was a disappointing snack There was no entertainment on this flight, but I did not expect any

I flew premium economy and this was a good option. Although the seats didn’t recline much, I was able to get some sleep with my head propped against the window. The food was good and the entertainment was wonderful The staff were very attentive and professional

Overall very poor. Flight was disorganised, staff were rude and this is my second experience with KLM that I've had baggage go missing. It feels like, if you are an economy customer, KLM staff do not show you any care. I shall never fly with KLM again. Worst airline in Europe

Great boarding, great short flight but no entertainment whatsoever and no wifi. Prepare to disembark by a staircase.

Transfer at CDG to connecting KLM flight to Amsterdam was a NIGHTMARE. LONG WALKWAYS, NO MOVING WALKWAYS, POOR signage, Have to take a train & No staff visible to help navigate the maze. AVOID TRANSFER AT CDG AT ALL COST.

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,

Flight took off an hour late. Had to stay on the tarmac for half an hour after landing. Both annoying.

We had an unfortunate experience where we had to leave the aircraft after boarding, shortly before the scheduled takeoff time, and re-board. The reason given was that a passenger felt ill and had to cancel their plans and therefor their luggage had to be found and removed.

We’ve used VA before many times the experience is always been good they have lovely staff and the food is always delicious.

Everything about the flight was amazing from check in to boarding entertainment was okay food we didn’t try.

Flight was full, and would have preferred an aisle seat, but due to getting a late ticket ,the seat I had was adequate. The flight crew were very help full and hard working. Food and drink were excellent for the 11hr flight. Overall I was pleased with flight, and would recommend British Airways again.

More choices on menu. Seemed only thing offered was Scottish, and while that’s good for the Scot’s it doesn’t help the Americans who don’t like that food. And I really hate it when, during sleep time the attendants have a very loud conversation right over you. Lastly, I paid 5000 dollars for business class, and having to pay more to choose my seat early is really an insult. Seems greedy

More choices on menu. Seemed only thing offered was Scottish, and while that’s good for the Scot’s it doesn’t help the Americans who don’t like that food. And I really hate it when, during sleep time the attendants have a very loud conversation right over you

The chicken adobo was a little too spicy but good otherwise. My personal opinion. Movie selection could be improved, too many horror movies. Could add a few more chick flicks! The flight was bumpy at times. We arrived a little early too! Flight attendants friendly.

Again flight was awesome except British Airways lost both gate checked luggage’s. Still missing

really bad they refused to check in luggages that I had purchased, even showing them the transaction receipt from british airways app the staff in miami was MEDIOCRE

Crew was great and responsive. Entertainment quit working with about 4 hours remaining on the flight. My seat cushion was broken.

Not very good , the stewardess were unfriendly and they don't like to be bothered. Cos was a night flight and they need to sleep.

British Airways staff are very polite and willing to help.

Two flight changes before the scheduled flight. On the day of the flight, the flight was delayed, which caused the connecting flight to be missed. Then, I was directed to another airport (CUN) and traveled to Tulum. American gave a $12 voucher for lunch. The least expensive item on the menu at a Mexican restaurant was $9.99. Driving to Tulum was a bad auto crash, and traffic was delayed two-plus hours. The bottom line is that we should have been at the hotel at noon, but it ended up at 11:30 PM.

Flight was delayed but the real issue is how long we sat after boarding. Space very limited for an overnight flight and seatbacks didn’t recline so it was almost impossible to sleep.

The staff made sure I was comfortable, moved me to a better seat with more leg room

Easy boarding and comfortable seating were plusses. Enjoyed the experience and good service from the captain and crew. Many thanks...!

Somehow, my booking was under my preferred name instead of my legal name so they almost didn’t let me board the plane at LAX. This problem should have been notified to me when I was still in Toronto.

Great overall. Quick boarding, attentive staff - great experience in premium class.

When arriving over 2 hours early to check k in at Charlotte airport I was told I would have to check my carry on ? Apparently the flight was full and may not be room. I was not given a choice and the agent was quite unpleasant about it. I am a senior amd was not comfortable me having to worry about my bag being lost vut it didn’t seem to bother him. There were lots and lots of people of all ages in line when we boarded with carryons and most larger than mine .the rest of my journey was pleasant vut this was totally unacceptable.

The layover was 6 PLUS hours and we were only given a $15.00 voucher. We missed our first activity in Quebec due to the delay.

Miserable staff as it was a late/delayed flight and crew wasn’t in the best spirits. Completely understood as neither was most of the passengers. Still unacceptable l.

Or the greatest and it ended up picking us up from Chicago to Toronto not sure who was tesponsible for the 4 hr delay. United should have been properly prepared for a scheduled flight from Austin to Chicago and they were not.

It was a short flight, and no entertainment. That was not a problem for us, but there is no option for "not applicable". There was a bit of turbulence, so there was no food service.

The payment system was not working so was unable to connect wifi the entire flight

everything to do with KAYAK was terrible. Your customer facing departments are utterly useless, timewasting and unhelpful.

I ordered short ribs for main course. It tasted sweet, really sweet. Horrible.

The screen didn’t work and I didn’t get the seat upgrade I paid $300 for. They were no help with that,

Paid $180 for seat selection, and selection essnt honored. Have to call for a refund.

My flights were great and the crew on them was lovely especially the London to Barcelona flight as Al & AJ were so amazingly nice. I wish they would be my crew always as they have the best customer service. Sadly both flights were delayed the first one from Vegas was because they clearly loaded the cargo wrong the plane was off balance making us 2 hours late. This made me miss my connection and sadly it was challenging rebooking while I was on the flight. I will never use Kayak again as there was no customer service number or live chat and you rebooked me on a flight 2 days later. I had my mom call BA to change it which she did after spending an hour on hold. This should not be so difficult. My second flight was an hour delayed due to not being able to disconnect the bridge from the plane but I did finally make it home.

The delay was not communicated via text and the person who helped with check in also didn’t inform me about the delay. I ended up missing my connection and it was a waste of 5 hours. The crew didn’t mention there would be someone at the gate informing of if I would be rebooked and there was no signage. Overall a very poor experience. The British Airways app was also very buggy, and didn’t work. I will avoid flying with British Airways when possible.

A little better than outward journey but mild chaos at the boarding gate because some people with boarding cards from connecting flights had cards which weren't recognised

The BA business class cabin is excellent,very comfortable for sleeping but the service could be improved.

Surly rude flight attendants. I ordered the chicken and was given a vegetarian meal with no explanation and no opportunity to change it. I tried to order another beverage and was told by the young humorless flight attendant to “wait”. And she never came back. The seats were very uncomfortable and cramped. The last time I flew British Airways was many years ago but I remember it was amazing and the crew were very charming. This was a terrible disappointment given the cost of the flight.

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