STL - LHR

$346 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 3/28. 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, 0 bags

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.
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to London.
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Everything you should know

Cheapest round-trip
$704
Overall average: $976
Virgin Atlantic
Sun 5/3Tue 5/12
STL - LHR • 1 stop
Cheapest non-stop
$805
Finnair
Sun 5/3Tue 5/12
STL - LHR • Non-stop
Nonstop flights
Tue, Wed, Fri, Sun
You can fly direct with British Airways. Average duration is 0
Direct flights
Direct flights
+1
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Direct flights
Direct flights
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Top airlines
Cheapest • from $704 (round-trip)
Best reviews • 7.4 score
Airline reviews
Airline reviews
+1
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Airline reviews
Airline reviews
+1
Top layover airports
Cheapest • Avg $728 (round-trip)
Shortest trip • 10h 52m (one-way)
Insights
Insights
Insights
Insights
When to book
in advance
Our data shows that travelers who book at least 2 weeks in advance save around 13% compared to booking last minute.
Insights
Insights
Insights
Insights
When to travel
Cheapest • 20% price drop
Most popular
Good to know
Good to know
+1
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Good to know
Good to know
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Start a new search
KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Heathrow!
Flight Deals
Booking Insights
Flight 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 round-trip 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 round-trip flight deals from St. Louis to Heathrow

Sun, May 3 - Tue, May 12
Virgin Atlantic Logo
4:41 pm - 1:15 pm
STL
-
LHR
14h 34m
1 stop
Virgin Atlantic Logo
6:15 am - 5:16 pm
LHR
-
STL
17h 01m
2 stops
$704Virgin Atlantic
Sun, May 3 - Tue, May 12
Finnair Logo
5:21 pm - 10:30 am
STL
-
LHR
11h 09m
1 stop
Finnair Logo
8:55 am - 7:30 pm
LHR
-
STL
16h 35m
1 stop
$715Finnair
Sun, May 3 - Tue, May 12
Finnair Logo
9:40 pm - 11:40 am
STL
-
LHR
8h 00mnonstop
Finnair Logo
3:15 pm - 10:19 pm
LHR
-
STL
13h 04m
1 stop
$716Finnair
Sun, May 3 - Tue, May 12
Air Canada Logo
2:20 pm - 10:00 am
STL
-
LHR
13h 40m
2 stops
Air Canada Logo
6:50 am - 8:25 pm
LHR
-
STL
19h 35m
2 stops
$731Air Canada
Wed, Apr 15 - Wed, Apr 22
Finnair Logo
12:27 pm - 7:55 am
STL
-
LHR
13h 28m
1 stop
Finnair Logo
4:25 pm - 7:30 pm
LHR
-
STL
9h 05mnonstop
$737Finnair
Tue, Apr 28 - Tue, May 5
Air Canada Logo
4:05 pm - 11:50 am
STL
-
LHR
13h 45m
1 stop
Air Canada Logo
5:15 pm - 8:25 pm
LHR
-
STL
33h 10m
2 stops
$739Air Canada
Sun, May 3 - Tue, May 12
Finnair Logo
9:40 pm - 11:40 am
STL
-
LHR
8h 00mnonstop
Finnair Logo
3:15 pm - 10:19 pm
LHR
-
STL
13h 04m
1 stop
$740Finnair
Tue, May 5 - Tue, May 19
Lufthansa Logo
7:09 pm - 6:25 pm
STL
-
LHR
17h 16m
2 stops
Lufthansa Logo
9:00 am - 9:13 pm
LHR
-
STL
18h 13m
2 stops
$741Lufthansa
Tue, Apr 14 - Tue, Apr 21
Finnair Logo
12:27 pm - 8:05 am
STL
-
LHR
13h 38m
1 stop
Finnair Logo
4:25 pm - 7:30 pm
LHR
-
STL
9h 05mnonstop
$742Finnair
Wed, Apr 15 - Wed, Apr 22
Finnair Logo
12:27 pm - 7:55 am
STL
-
LHR
13h 28m
1 stop
Finnair Logo
12:15 pm - 10:17 pm
LHR
-
STL
16h 02m
1 stop
$743Finnair
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.

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 $670 (return) on average. On the other hand, the most expensive months are June and July, where the average cost of round-trip tickets is $1,296 and $997 respectively.

Can I save money by flying with a layover from St. Louis to London Heathrow Airport?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

No, with an average price for the route of $763, prices are generally cheapest when you fly direct.

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 2 weeks before departure, which saves you about 13% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 3 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flight$346
Best time to beat the crowds but there is an average 2% increase in price.
Most popular time to fly with an average 16% increase in price.
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 round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips 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 $346 for a one-way ticket and $704 for a round-trip.

  • Do I need a passport to fly between St. Louis and London Heathrow Airport?

    A passport is required to fly from St. Louis to London Heathrow Airport.

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

    St. Louis and London Heathrow Airport are both served by 1 main airport. You will leave St. Louis from Lambert-St Louis and will be arriving at London Heathrow.

  • Which airlines offer Wi-Fi service onboard planes from St. Louis to London Heathrow Airport?

    American Airlines, Lufthansa, and United Airlines offer inflight Wi-Fi service on the St. Louis to London Heathrow Airport flight route.

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

    The Boeing 787-8 Dreamliner is the aircraft model that flies most regularly on the St. Louis to London Heathrow Airport flight route.

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

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

  • On which days can I fly direct from St. Louis to London Heathrow Airport?

    You can catch a nonstop flight from St. Louis to London Heathrow Airport on Tuesday, Wednesday, Friday, and Sunday.

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

    The two airlines most popular with KAYAK users for flights from St. Louis to London are Delta and KLM. With an average price for the route of $852 and an overall rating of 7.9, Delta is the most popular choice. KLM is also a great choice for the route, with an average price of $643 and an overall rating of 7.8.

  • 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 travelers 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 round-trip ticket. You could then fly to London Heathrow Airport with an airline and back to St. Louis with another airline. Booking your flights between St. Louis and LHR can sometimes prove cheaper using this method.

  • 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.

KAYAK’s top tips for finding a cheap flight from St. Louis to London Heathrow Airport

  • Looking for a cheap flight? 25% of our users found flights on this route for $535 or less one-way and $864 or less round-trip.

Prefer to fly direct from St. Louis to London Heathrow Airport?

 
Direct data is based off flight results for the next 60 days. Find direct flights from all airlines flying direct from Lambert-St Louis to London Heathrow.
Find which airlines fly direct from Lambert-St Louis Airport to London Heathrow Airport, which days they fly and book direct flights.

Direct departures

Lambert-St Louis to London Heathrow

Tuesday

British Airways

British Airways

Wednesday

British Airways

British Airways

Friday

British Airways

British Airways

Sunday

British Airways

British Airways

See more direct flights

Direct returns

London Heathrow to Lambert-St Louis

Tuesday

British Airways

British Airways

Wednesday

British Airways

British Airways

Friday

British Airways

British Airways

Sunday

British Airways

British Airways

See more direct flights

Reviews of the 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.
7.4
United AirlinesOverall score based on 9427 reviews
7.1Entertainment
7.3Comfort
6.6Food
7.7Boarding
8.1Crew
Airline reviews

Wifi Bluetooth features for watching in flight movie was horrible. Screen kept blacking out no connection of sound although it said connected. Other than that smooth trip .

8.0 ExcellentAlissa, Mar 2026
TPA - EWR
Read more United Airlines reviews

Wifi Bluetooth features for watching in flight movie was horrible. Screen kept blacking out no connection of sound although it said connected. Other than that smooth trip .

The 777’s economy seat’s legroom was more tolerable than expected. I appreciate the reclining mechanism which slides the seat forward to minimize cannibalizing the space behind. The food was terrible: very salty.

The travel company that you have on your site did me so wrong. I don’t know how it happened, but they put my son‘s name on my plane ticket flying to Vietnam. Along with his birthday. They would not have let me fly from Fort Myers to Ho Chi Minh City. I don’t think that I can ever use your service again. I typed my information into the browser along with my passport number and four days before I’m leaving I have to quickly search another ticket to fly out here.

Seats are uncomfortable. This has been a trend in the industry for decades. Trying to fit more seats on each plane to increase profits at the expense of the passenger.

The flight was delayed so we were dead tired, and after that the turbulence was horrible. I was very scared.

It’s always a great time flying with united airlines.

Good flight. Efficient boarding and competent flight crew. No problems until we arrived at our destination gate. We were early so there was an aircraft at the gate that had to move before we could pull in. Then, due to the type of aircraft we flew, the cabin door could not be opened until some luggage from the cargo bay was offloaded to preserve center of gravity characteristics. So, that further delayed deplaning. Despite being 20 minutes early on landing, we ended up being 5 to 10 minutes late after all the delays.

Everything went well except the turbulence what no one have a control of but pilot and crew handled very good!

There was no WiFi available, there were mechanical problems with the plane and we landed at C 124, then the gate was switched to A 26, then all the way back to C126! For a 75 yo woman traveling alone, this was a difficult journey, indeed!

This trip did not start off well. The inbound flight was delayed about 20 minutes. Then, after initial onboarding, the passengers had to deplane due to a mechanical problem. That took about 30 minutes to fix and be cleared. Then, reboarding was chaotic. It took a long time to sort passengers and two passengers on standby were ticketed but there was no seat. So, they had to deplane. One of the flight crew was trying to help passengers figure out a place to put their carry-on bags and that took more time. In the end, our scheduled 10:30 am departure did not actually take off until about 12:05 pm CST. The flight itself was long but we got to Houston. Some passengers missed their connecting flights and had to rebook. Not the best of flights I've had.

Good level of service. Comfortable airplane. However, security is always a hassle at LHR. I always try to avoid that airport at all cost if possible.

Everything smooth. The only thing is that my connecting flight in the US to my final destination was delayed. The time changed 4 times. For the rest, everything on time without issues

My flight to London from Philadelphia was cancelled due to weather.

Disliked having to wait a little longer to disembark from the plan when we landed in London

Food should be better quality. Video screens have poor resolution and the library of movies is poor. The other airlines are much better.

The trip was smooth but the crew were very abrupt, snatching things before finished and being quite snappy when asked questions.

My wife and I love to travel, so we fly a lot. We've already logged 381,075 miles and with practically every major airline. But this flight was very disappointing. It started off well, with no delays and a new plane. But when lunchtime approached, all that good impression was ruined. Instead of white tablecloths, we were offered small, dark placemats, which, as it turned out, were perfectly adequate for the food. All the food offered—and my wife and I only took fish, and the meat—was not just bad, it was downright disgusting and not heated enough. The same applies to the appetizers. This was the first time in many years of traveling that we've been offered such disgusting food.

Lost luggage stuck no clothes and no word after 2 days leaving on cruise no stuff or clothes

Don’t know they cancelled the flight day before I was to leave. They sent a email at 9:00 pm at night saying they cancelled. That is the smooth way to say we don’t want your business! I think they didn’t have enough people booking so they cancelled the flight! It’s all about the money anymore there is no honesty in business.

The flight was canceled 3 hours after original take off time

Departed Palm Springs over an hour late because there’s only one gate, and it has always delayed by the arriving and departing flight to Toronto and the arriving flight from Vancouver.

I checked a bag and there was only one agent to assist all customers with any issues.

I want to thank Carlos at the Miami AC desk - he was amazing and went over and above to help us out. Thank you Carlos and all the best to you!!! You made our faith in AC feel great! Sincerely, David Cubitt

Flight was canceled due to mechanical issues. After a considerable wait in the queue, Air Canada customer service was very helpful to get us on another flight. I am disappointed to report our rescheduled flight is for three days from now. Three days of extra expenses and inconvenience is unacceptable.

Extremely disappointing. My original Denver–Vancouver–Bangkok itinerary was cancelled due to a crewing issue. I was not proactively supported and had to drive back home after already reaching the airport. Communication was poor throughout, and attempts to contact customer service resulted in being on hold for nearly three hours without reaching anyone. Instead of being rebooked on the same direct routing the following day, I was rerouted onto a much longer itinerary via multiple cities and airlines, which resulted in arriving approximately 30 hours later than scheduled. At Denver airport, there was no visible Air Canada representative available to properly assist. Ground staff offered no real support beyond directing passengers to a phone number. There was no clear communication, no ownership, and no meaningful customer care during a major disruption. The final journey involved three flights instead of the original two, significantly increasing travel time and stress. Overall, the handling of the cancellation and lack of customer support was unacceptable. What could have been better? Clear communication during the cancellation Accessible customer service (phone support that actually answers) Proper in-person assistance at the airport Rebooking onto a comparable routing rather than a significantly longer one

Great setup on both flights except the last flight we got condensed dripping all over me in the last 20 mins of the flight

The last 3 hours it was freezing cold in row 56. Multiple people had their winter coats on and were utilizing the blankets provided by the airline. I also did not have easy access to figure out how to book my food allergy and advance for my meals. Most of everything I received was something I couldn't eat. This needs to be made more accessible. Also, I'm 5'10 which is the average height of the American male. I flew from Philadelphia to Toronto and then to Tokyo and the seats were absolutely unbearable. For that long of a flight it is impossible to get comfortable when doing anything. Flights need to have more space and stop prioritizing costs over people.

Was delayed at every point/ connection. Luggages missing for 5days. Had no medications for diabetes and high B/p. when bags where finally delivered on the 30th, the insulin and ozempic were no longer patent, as the ice pack had since dissolved and the authenticity of the med is now questionable, since they must be refrigerated. Please have them refund my bag fees. I should sue them for all the inconveniences caused to me.

The plane was delayed substantially due to a mechanical problem, that being said, the airline was very fair with providing a meal coupon for us. I would rather arrive late on a mechanically sound plane than the alternative. The food served in the plane was just awful, however and I recommend a new catering company.

I liked the quiet airport and no queue. I don't like that when booking it is not clear that there is teared economy, that you have to pay extra for choosing a seat and for your luggage both ways. We didn't find this out until checking in. It turned out not very economical.

Flight was fine - however my husband's checked in case was damaged, and mine still has not arrived

Awful. They didn't even show concern that her connecting flight( Dallas to Mardrid) was gone/missing. I don't understand how that is even possible. Rudest answer from one of the crew was that American Airlines sold the tickets to somebody else. My daughter was not in the list.

The flight was canceled on a Thursday last minute. I lost thousands of dollars in hotels and car rental

Excellent lie flat seat for premium economy! Great staff. Bad food . Not so great entertainment. My bag didn’t make it either.

Really like the idea experience on this airline I will use again

The boarding procedure got confusing because they wanted to weigh everyone’s carry-on. Apparently mine was 3 1/2 kg over their limit. I didn’t know they had a limit. And at the check-in desk, nothing was said about this. They wanted me to check the carry-on at no charge and that would have been fine except then they told me at my connection in London I would have to go outside to baggage claim retrieve my bag, and then recheck it. In other words, they could not check it to my final destination, only to London. I told him this was unacceptable so after a few minutes of discussion, they came back and said that my bag would be OK to carry on the plane. It seems that if you have a connection then the weight is not as important. Then when I actually went to board the boarding agent said I needed a tag indicating that my bag had been weighed, even though she had just five minutes ago talked to the same person who cleared me. Lots of confusion seems like a very bad process. They need to improve this.

My flight being automatically moved messed up my travel plans, and I had to quickly find an alternative mode of transportation. I couldn’t get a refund from any of the companies involved. Kayak, Ibiza, or Vueling. I am still unsure of how to settle my concern.

Plane delayed due to weather. Plane boarded, then told to unboard due to a maintenance issue.

the seats were so cramped you could barely move. it was difficult to eat when passengers would recline their seats. the seats were so flimsy and unstable that whenever someone got in and out of their seat, it bounced like a spring back in your face. the movies were nice. the food was terrible. even though the conditions were terrible, they tried to pressure passengers to relocate their seats to accommodate adults who were related and wanted to sit next to each other, even after the passengers expressed that they did not want to move for that purpose. on the connecting flight, the “service” consisted of items for purchase. even though the flight was only 45 minutes, once again passengers (including me) were pressured to relocate for people to sit next to each other. they couldn’t be apart for 45 minutes? this was much less compelling than being apart for an 8 hour flight.

Everything went smoothly, and we even arrived 40min earlier than scheduled, on an Orland-Madrid route.

Worth every penny to upgrade to BC. Treated and felt more like First Class

Good service, food and comfort in World Traveller Plus. Entertainment was poor - no wifi on the way out and barely working on the way back. Not a great choice of entertainment on the seat back tv.

They had us seating down for one hour just waiting on the plane

Flying with BA is always a good experience—even in economy class. It is better if in business and first class. Timely, breeze through security and timely connections

We waited at BOS at the gate for an hour and couldn’t get a drink or anything. Once in the air the service, food and ride was excellent.

My enetertainmnet screen was broken. Lost my bags. Almost missed my flight do to connection issues with (despite a request) ZERO help from crew. Food was edible. Potatoes pretty good even

The issue was not with BA it was with the link yoiu sent fopr booking the flight

Loved the boarding option from Business class lounge, experience on flight was excellent, plenty of good food choices

The airline was not clear about a new departure time so we got to the airport early anyway. The flight left early which was great because of weather. The check in process was very easy and staff were friendly and helpful. The crew was great and our flight was very good.

Awful it always is unfortunately is the only way to fly direct to london

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

Information on your arrival and departure airports