Find cheap flights from Colorado to London

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Find cheap flights from Colorado to London

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London
Tue 5/11
Tue 5/18
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Low season

AugustBest time to beat the crowds with an average 20% drop in price.

High season

SeptemberMost popular time to fly with an average 50% increase in price.

Average price round-trip

$491(avg. price over the last 2 weeks)

Good deal round-trip

$70or less

Good deal one-way

$88or less

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Top 3 airlines serving Colorado to London

Scores according to KAYAK customer reviews

7.9
Delta
Overall score based on 29,242 reviews
8.1
Boarding
7.8
Comfort
8.5
Crew
7.8
Entertainment
7.5
Food
Airline reviews

Cons: "100% as always.. delta has never disappointed! Keep up the good work guys"

Cons: "Delta.... they’rrrrrr Grrrreaaate!"

Pros: "Most of the crew was great with the exception of curbside check-in in Denver."
Cons: "Curbside needs to stop chasing cash tips and do their jobs. If they focused on that tips would be easy to come by. The curbside attendant that took my bag didn’t even bother to check my id. He asked me my name and asked where my destination was. I told him Cincinnati as a layover then LaGuardia where he said that was wrong. He then proceeded to print a boarding pass that wasn’t mine and load my bag into the conveyor. Not 5 mins go by when I realize what happened I wound up having to go to special services to rectify the situation. Which ultimately consisted of me waiting another hour in LaGuardia to get my bag. Please delta have these curbside handlers actually want to do their job and stop chasing cash tips."

Pros: "Good"

Pros: "Flight left on time and landed on time"

Pros: "Quick flight...ahead of schedule"
Cons: "Cheese It’s are boring...miss the snack mix"

Pros: "Flight was delayed for more than 3 hours."
Cons: "Could have left on or close to schedule."

Pros: "Comfort + was nice."
Cons: "Had a middle seat between two other men. I was given my seat by the gate. It would have been nice if they placed my more strategically. That might be asking too much but seems reasonable."

Cons: "Choice of healthier snack"

Pros: "Nothing spectacular."
Cons: "The headrests won’t stay up. And it’s hot."

Cons: "Have rhe right to carry at least one luggage per person at no cost. Besides carry on and personal item. Tickets prices and luggage costs are extremely expensive."

Pros: "Staff from Check in to aircraft very pleasant. Snack choice in Coach impressive."

Cons: "Uncomfortable chairs for a three hour flight"

Pros: "Nothing"
Cons: "I bought a ticket thinking i bought it through kayak but I actually bought a ticket through a third party in India. Where no one spoke good English. I called the agency to find out if I needed a Visa for my visit to Australia and the told me no. So when I showed up to the airport I didn’t have the right documents and I MISSED MY FLIGHT. Also the wouldn’t just change my flight and charge me the change flight fee. They cancelled my flight entirely and made me buy a whole new ticket!!! Worst flight experience I’ve ever had and this is not my first time flying to Australia or out of country."

Pros: "Very friendly gate attendants helped us fix the problem that our frequent flyer number had not been entered on the boarding pass. This may have been because of the booking co., Just Fly."
Cons: "Would have liked more seat options, like when I book on Delta's website. Didn't have enough advance warning."

Pros: "Check in Denver super helpful Gate staff hustled to turn around flight Flight crew excellent"
Cons: "Flight delayed, almost missed international connections"

Pros: "Boarding, friendliness of staff"

Pros: "Everything was easy and smooth."

Pros: "Anything from free WiFi, entertainment, leg room, commentary drinks and snacks. Great service!"

Pros: "Short flight"
Cons: "In SLC they boarded by row numbers and not zones. Weird..."

Cons: "Was unclear which zone was boarding. Legroom was comprised when passenger in immediate row ahead reclined seat early in flight."

Cons: "Engine problems-2 hour delay"

Pros: "The fact that there was a screen for movie selections and a charging port for my phone and the flight attendants were super nice"

Pros: "Good flight crew"
Cons: "Delayed due to mechanical issues. For 3 hours. No offers for free drink or wi fi. When we finally land we were on the runway for half hour."

Pros: "Everyone was fairly friendly"
Cons: "Cramped foot room"

Cons: "Bags never arrived at the listed baggage claim. After 45 min, I saw bags on a different claim station and I notified everyone standing around. BUT, I filed a claim with Delta and was immediately given 2500 miles, as guaranteed!"

Pros: "Great people and crew early arrival nice passengers"

Pros: "Nothing!"
Cons: "Everything"

Pros: "Delta is great"

Cons: "The crew forgot to turn the heater on in -3°F creating a situation where the lavatory water lines froze. This caused a two hour delay which made me miss the second leg. Because I missed the second leg I was put on the very last flight out of ATL and got to spend Xmas eve in the airport."

Pros: "Crew was nice."
Cons: "The Entertainment sucked. Again I was sitting in comfort class which in theory should buy you more comfort and better entertainment. There was a ton of movies from the 90s and the same movie selection from about 6 months ago when I traveled with them. Also, what is going on, with having to use your own cell phone to watch movies on the plane? Whatever happened to the screens in the backseat of the front seat? I ended up with neck pain from trying to watch a movie on my phone. Delta has become very cheap. It is going into some serious decline."

Pros: "Nothing"
Cons: "Let me just say that I’m a loyal Delta costumer until now. The flight attendants (the two women) were an absolute nightmare. They were so rude and condescending. I was carrying with me my service dog and a bag containing an expensive medication (it couldn’t go on the top bin). Despite being in the comfort class and having the seat next to me empty, we were tight for space. The flight attendants were unreasonable and forced me to put my medication on the top bin despite the fact I had told them it was extremely delicate, that it that to go upright, and that I needed to keep it with me. They did not listen and pressured me into giving them the medication. The medication could have easily gotten broken. Thankfully it didn’t but this is no way to treat a human being."

Pros: "What a city.. Unique for hell sure..."
Cons: "Nothing"

Pros: "Crew was the best!"
Cons: "I really dislike the snack boxes. Snacks need to be more like a small sandwich or grapes, cheese and nuts. Not all that packaged stuff."

Pros: "Boarding super excellent! Also: Best landing I've ever experienced! Props to the pilot!!"

Pros: "Staff pretty friendly. Plane clean. Ran on time. Good communication. Even though shorter flight, had movie entertainment option. Before flight we had a flat tire so missed our flight. Agent extremely helpful getting us on another flight."

Pros: "Newer plane with movies."
Cons: "Airlines pack you on so tight."

Pros: "We purchased economy tickets in Delta. With these tickets you don't know where you are sitting until you get to the airport. Well, we lucked out and got the Plus seats! We got free alcoholic drinks, and big plush seats! We left right on time and got there early! Overall a great experience!"
Cons: "Nothing."

Cons: "I fly Delta quite often, and am usually pleased with their service, but the morning of June 23 was terrible. I got to the airport in Denver at 5:30 am for a 7:30 am flight to Atlanta, and the line to check a bag was about 40 people long. I waited 55minutes to check my bag, as they kept moving the ski priority people, and people in danger of missing their flight, to the head of the line. There were obviously not enough Delta workers on staff to process all the flights at that time."

Pros: "The moviea"
Cons: "The time of night"

Pros: "Everything else fine."
Cons: "Made me check my bag - even though ther was plenty of overhead bin space."

Pros: "I didn't like anything because the fly leat 3 hours"

Pros: "Smooth ride. Delta got everything right from takeoff to landing."

Pros: "The flight attendants were so nice and accomadating. Even came by to refill our waters! I've never been on a flight with such friendly flight attendants!"

Cons: "I drove 5 hours to get to the airport and unfortunately ended up delayed because of traffic and slow shuttles from parking. I arrived 1 hour before the flight, but security was so slow I didn't get to the gat until 10 minutes before arrival. There were no gate agents present and despite banging on the gateway door and other Delta agents at the adjacent gate, no one helped me. I can only surmise that they had already given away our seats, which were award tickets, GAINED BY BEING A LOYAL DELTA CUSTOMER. The gate agents were unapologetic and useless at rebooking, and I bought a ticket from Southwest instead. As i was trying to get to my sister's wedding, and repeatedly told the agents this, their behavior was particularly abominable. DELTA, YOU'VE LOST A LOYAL CUSTOMER."

Cons: "Seats too close - I'm not that tall and my knees were jammed against the seat in front of me."

Pros: "Plane was clean and staff were friendly"
Cons: "The snack options were quite average"

Pros: "Excellent customer service. That doesn't seem to happen too often with airlines. Delta has been outstanding."
Cons: "No complaints."

Pros: "on time travel care in treating my visitors from Kenya Africa"

Pros: "They cancelled the flight"
Cons: "How about a refund?"

Pros: "Quick and very organized"
Cons: "Snacks and beverages"

Pros: "The crew was super friendly and took great care of us. The food was surprisingly good and our seats were comfortable. It was worth upgrading to Premium for the extra legroom and other little perks."
Cons: "I really can’t think of a bad part...the customer service at check in was so easy; our checked bags were automatically transferred in Calgary, the crew was very friendly, food was good as was the wine and beer."

Pros: "On-time flight, satisfactory crew."
Cons: "Seat felt cramped (not helped by overweight guy next to me), plane was warm with very mediocre airflow, window seat was missing window."

Pros: "Nothing to be completely honest"
Cons: "Airplane was old and dirty. Flight attendants were extremely rude and condescending. The plane arrived nearly 3 hours late. Boarded 30 minutes late waited on the tarmac for an additional 2 hours while they performed maintenance. They ran out of food for what was now an 8 hour flight. Starving!"

Cons: "The flight was full and my carry-on had to be checked due to other passengers bringing oversized carry-on. The beverage service did not occur until 10 minutes before landing. Options were limited to water only. The flight was extremely rough and the pilot slammed the plane on landing."

Pros: "Crew was great."
Cons: "In flight entertainment was poor. Seat was poor."

Pros: "Crew not attentive unless you were in club class"
Cons: "Didn’t really expect much it was okay"

Pros: "Direct from Orlando to London!"
Cons: "Coming home to the cold"

Pros: "The pilots made the trip in great time. The landing was good."
Cons: "We were told we could board the flight, then when we got to the steps in the cold and dark we were sent back.The staff were not very friendly with the customers somewhat superficial, but with each other it was like they were at a party. Not impressed by the 2 young women."

Pros: "NA"
Cons: "NA"

Pros: "I fly frequently and this is the first time I've travelled with West Jet. The big difference was the staff. Unlikely many airlines the West Jet crew - in flight and the ground crew - were all very friendly, helpful and actually seemed like they enjoyed their jobs. I called West Jet prior to checking in on-line and my call was answered within a minute by a real human who was so helpful. That's the polar opposite of so many airlines like Air Canada."
Cons: "The seats are too close together but that's not unique to West Jet. And the in flight crew was so helpful that it makes up for the lack of space."

Pros: "The WestJet staff took great care of my dad right from when we entered the airport in Calgary to when he landed in Phoenix. They made sure he was comfortable and that his experience was stress free."
Cons: "No control over this but they waited on the tarmac for 30 minutes before taking off. They made up the time in the air. I'm sure that de-icing the plane was the reason for part of the delay. Safety first."

Pros: "Boarding, flight, and deplaning great.our seats were pre booked by West Jet and were the window and aisle seat. My husband is 6’5” and needs an aisle seat. We prefer to book our own seats at no cost. Fortunately our seat mate wanted to change too."

Pros: "The staff on board made us completely forget we just experienced a terrible 6 hour experience in the hands of westjet from punta cana. The airport staff and security were efficient and all friendly. Helped us every step of the way. But again, a big thank you to the 4 flight attendants on the ws 254 to Halifax. Made our crappy day much better simply by being a friendly and happy face."
Cons: "Didnt like having to connect but understand that was to my own booking."

Cons: "Limited snack, no entertainment without a tablet of some type. Cargo restraint broke and delayed the flight for an hour."

Pros: "The crew."
Cons: "No entertainment on board"

Cons: "No entertainment service."

Pros: "The staff was really friendly and accommodating"
Cons: "The plane had no onboard entertainment system and most of the plane had malfunctioning power supplies for your personal device. the plan was not clean and the pilot Had a horrible landing."

Pros: "Short flight"
Cons: "People were cramped in the plane, hardly any room for bags. People from other seats were packing their bags on top of other peoples stuff"

Cons: "On time"

Pros: "Good service. And snacks served"

Pros: "Amazing Service at the registering counter at the airport. One for the two flight attendants was very nice. Unfortunately, he was not the one assigned to my section."
Cons: "One of the flight attendants was incredibly dismissive. “Forgot” to ask for my order to get lunch, so needed to call him so he could take my order (he was already in the middle of eating his own food) and of course by then what I asked for was not available, and the options for food were bad. On top of that, the trash from the top of my table was not cleared for a long, long, long time (even though everyone else’s in my section were clean). First time this happens to me in all my years of flying, specially in upper economy class."

Cons: "I had safety concerns on the flight from YVR to Toronto because seated in the exit row were two individuals who were brought to the gate assisted on a cart and had to wait for assistance to get on and off the flight. They had very poor ambulation which made me nervous as these people have agreed, by sitting in the exit row, that they are able and willing to help in the case of an emergency evacuation. This was not a safe situation and was noted by several passengers."

Pros: "The over all star rating should have five stars. I mistakenly pressed something and it went to one And I could not figure out how to get it back to five. Everything was on time which I so appreciated."

Pros: "I’ve always liked WestJet and it’s services. They are my always my first airline I go to check flights."

Pros: "Professional, efficient, courteous."

Cons: "Plane seemed older and less leg room for a 6’4” guy. No TVs or monitors to track flight info."

Pros: "Crew good, service good"
Cons: "Both flights delayed over 2 hours, missed connection so it took so I was in airports 13 hours instead of 6"

Cons: "I will say our flight took of a bit late which was a bother so late at night."

Pros: "It was a clean plane and a pleasant enough flight."
Cons: "I was in the window seat. The guy in the middle seat spread out so much he was pushing me against the side fo the plane. Really uncomfortable."

Pros: "Very smooth flight."

Pros: "Plane was clean"
Cons: "Waitjet did not perform preventative maintenance and had to change a tire at Gatwick delaying flight by 2 hours with terrible/late/inaccurate information about when flight would resume = FAIL Result was overnite in Toronto. Lets see how the 6:45 (3446) goes ?"

Pros: "It is inconvenient to disrupt your plans with such delays"
Cons: "It is inconvenient to disrupt your plans with such delays"

Pros: "Speed of Service"
Cons: "Wish flight attendants were demonstrated more interpersonal skills."

Cons: "ONE WAY TICKET Vancouver TO Tel Aviv was about $560 c.d -all- included. Went well 3 flights well. Ticket back from Tell Aviv took 4 flights , around $900cd . had to pick-up the suitcase each airport.., and pay for the suit case separately.."

Pros: "Staff are friendly"
Cons: "The on board menu only caters to rabbits and squirrels. I get some people like to eat that way but what about the other 80 percent of the population????"

Pros: "The WestJet staff, from gate check in to the flight crew, were excellent."
Cons: "The fact that people with pets board first is ridiculous enough to keep me from choosing WJ as my first option. They boarded before seniors and children. What has happened to our crazy world that pets are more important than people."

Pros: "I had my mom who needed wheel chair assistance, and an agent helped push her and made sure she was comfortable. I couldnt have asked for anything more. Very appreciative of the considerate service and help."

Pros: "Staff were so friendly and helpful"

Cons: "plane just stood and everyone just sat on the plane for a solid hour an a half. I almost missed my connecting flight with another airline."

Pros: "Landed 10 minutes early. Good landing in tough conditions"

Pros: "Got to my destination..."
Cons: "Westjet will nickel and dime you for everything. Did a +9h flight from Vancouver to London and no meal is included during the whole flight. They keep trying to upsale you for everything. Not only is the food expensive it is also real garbage. Flight was delayed by 75 minutes and nearly missed my connection. Of course no checked baggage is included in your already expensive ticket. You have to fork in another 30$ for the privilege of checking luggage. WestJet pretends to offer 200-300$ cheaper plane tickets compared to the competition, but this is false. I found plenty of other flights for same or even cheaper prices with quality airline companies like Lufthansa or Air Canada that include a meal and checked baggage and other perks, but in my case I had already booked. I really recommending you looking for other airline companies for any flight that is not short haul. WestJet's slogan is an airline company with owner that care... Whatever the hell that means. Maybe someone can explain? WestJet brags about it's outstanding customer service while at the same time cutting every corner possible on service. Kind of a contradiction."

Pros: "Staff tried to do what they could but unable to really do anything. They only repeatedly messed up boarding passes causing me to miss flights."
Cons: "The planes were not in working order. The first plane had a hole in it from hitting something the flight was completely cancelled only one out of the two people at the counter was helping a line of people, but due to a system error people were not checked in . I had to get 4 different print outs of my boarding pass. the second aircrafts air conditioner didn't work, the third plane the back door would not close. I spent over 12 hours in the airport and couldn't get home till the following day . The airline did not have a hotel reservation ready as promised and had to wait an additional 15 minutes while they were telling me I was responsible for my own room. Eventually they got me a room and gave me a voucher. I would never fly or recommend West Jet i just don't feel safe."

Pros: "Great atmosphere... entertaining staff, very pleasant."

Pros: "On the way back boarding started early and we left earlier than planned."
Cons: "Boarding has become quite the painstaking endeavor since all checked luggage is payed because now travellers try to fit everything in carry ons to save money which leads to everyone trying to put their stuff in the overhead bins. This isn't exclusive to one carrier though."

Pros: "Leg room"
Cons: "Unprofessional staff. Made a mistake during boarding that caused 2 hour delay"

Pros: "The staff with West Jet are extremely helpful and friendly. I wish the American carriers would take lessons from them."

Pros: "In-flight crew was great!"
Cons: "Manager and crew at the check-in counter are incompetent!!!"

Pros: "WestJet staff and crew fantastic"

Pros: "Good job"

Pros: "Good job"

Cons: "Smiles on statements. Plane was freezing cold. Lite didn’t work."

Pros: "Wheel chair service"
Cons: "A/C outlets and bathroom sink did not work"

Cons: "not delayed would surely have been better"

Pros: "Great"
Cons: "E-175 is very comfortable"

Pros: "Nothing. United has a long way to go."
Cons: "Food is terrible. Honey nut cheerios is the only cereal choice, great for diabetics."

Cons: "Glad we were able to watch a movie"

Cons: "I was sitting two rows from the bathroom and the entire time the bathroom reeked of urine. It was unbearable."

Pros: "The stewardess was very attentive"
Cons: "We waited about 20 min to take off and ended up coming in 30 min. late"

Cons: "The upgrade standby list was never cleared. My production assistant was number 1 in line for an upgrade and didn’t get it because someone at DEN forgot to do their job."

Pros: "Read above"

Pros: "Kept getting bumped into"
Cons: "Hospitality"

Pros: "They were effective at boarding"
Cons: "My display monitor didn’t work"

Cons: "Delayed landing and takeoff because of unprepared crews"

Pros: "It was on time"
Cons: "Snacks from Lax to Denver"

Pros: "Excellent landing"

Pros: "On time and great professional staff throughout"

Pros: "Free WiFi with movies"

Pros: "Smooth landing!"
Cons: "Late 30”"

Pros: "Never made it to Denver"

Pros: "Look at box above."
Cons: "Look at boxes above!"

Pros: "Selection of films and TV"
Cons: "Late boarding, but no apology. Drinks service, but no snacks"

Pros: "Fast easy"
Cons: "Pricey"

Cons: "I never got there."

Pros: "Food was great"

Cons: "I was very cold!"

Pros: "Nothing unusual"
Cons: "Nothing unusual"

Pros: "Everything ran as expected"
Cons: "Nothing"

Pros: "N/a"
Cons: "N/a"

Cons: "Very bumpy ride....but I realize that can't be helped"

Pros: "Amazing plane with great features! Incredible staff!"
Cons: "Bathrooms should be bigger"

Cons: "Delayed and got downgraded"

Pros: "There was a lot of space and a quick departure."
Cons: "When we got to LA event though we were early we had to wait. I know its not the airlines fault but it sucked."

Cons: "Nothing"

Pros: "The kindness of the staff."
Cons: "Having to go back to Denver because of a storm-in Omaha."

Cons: "Great employees!"

Pros: "A everything was fine other than..."

Pros: "Love the free tv/movies with the United App. That was great!"

Cons: "Delayed 3 times. United is known for delays, everyone jokes about United delays!"

Cons: "Their plane broke down, no assigned gates ,"

Pros: "Everything went as planned"

Cons: "No compliementary snack. Customers that pay to check their bags should get a snack included with the cost of checking a bag."

Pros: "Plane was fine, but very cramped."
Cons: "Seat was very cramped. Overhead bins are too small and had to gate check my carryon."

Pros: "nothing"
Cons: "t was delayed without informing me i stay in airport 6hours"

Pros: "Met a cute girl!"

Pros: "United is predictably competent and professional."
Cons: "The seat pitch is very close in coach. Being already 3 by 3 on the A320, sitting at such a close pitch is uncomfortable."

Pros: "Small plane completely booked."

Pros: "Smooth with courteous staff"

Pros: "I recomend it..."
Cons: "No complementary food!!!"

Read more about Delta
COVID-19 information

Safety measures for airlines flying from Colorado to London

Airlines flying from Colorado to London have enacted additional safety measures and adjusted policies to better accommodate travelers. Policies vary by airline.

Heightened sanitation

Daily cleaning, installation of cabin HEPA filters on flights from Colorado to London

Mandatory masks

Masks required on board, masks provided on flights from Colorado to London

Social distancing seating

Middle seats unavailable to book on flights from Colorado to London

Pre-flight testing

Testing for antibodies, testing for symptoms for flights from Colorado to London

Book cheap flights from Colorado to London

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