ONT - LON

$268 Find Cheap Flights from Ontario to London

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Ontario to London departing on 1/24. 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

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Ontario 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 Ontario to London, as well as popular online travel agencies
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Everything you should know

Cheapest round-trip
$579
Typical prices: $677-$988
Iberia
Tue 1/27Thu 2/5
ONT - LHR • 1 stop
Cheapest one-way
$268
Multiple Airlines
Sat 1/24
ONT - LGW • 2 stops
Top airlines
British Airways
Cheapest • from $609 (round-trip)
Delta
Best reviews • 7.9 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
When to travel
February
Cheapest • 16% price drop
June
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Ontario to London (ONT-LON)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Ontario to London 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 Ontario to London

Tue, Jan 27 - Thu, Feb 5
Iberia Logo
10:58 am - 10:00 am
ONT
-
LHR
15h 02m1 stop
Iberia Logo
8:50 pm - 10:48 pm
LHR
-
ONT
33h 58m2 stops
$579Iberia
Wed, Feb 25 - Wed, Mar 4
Iberia Logo
7:00 am - 11:40 am
ONT
-
LHR
20h 40m1 stop
Iberia Logo
7:35 am - 10:49 pm
LHR
-
ONT
23h 14m2 stops
$581Iberia
Wed, Apr 15 - Tue, May 5
British Airways Logo
4:52 pm - 3:05 pm
ONT
-
LHR
14h 13m1 stop
British Airways Logo
6:10 am - 6:37 pm
LHR
-
ONT
20h 27m2 stops
$584British Airways
Tue, Feb 3 - Tue, Feb 17
British Airways Logo
4:45 pm - 1:15 pm
ONT
-
LHR
12h 30m1 stop
British Airways Logo
11:45 am - 7:45 pm
LHR
-
ONT
16h 00m1 stop
$589British Airways
Sun, Feb 1 - Thu, Feb 12
British Airways Logo
3:09 pm - 12:15 pm
ONT
-
LHR
13h 06m1 stop
British Airways Logo
4:30 pm - 11:59 pm
LHR
-
ONT
15h 29m1 stop
$590British Airways
Sun, Jan 25 - Wed, Feb 4
Delta Logo
12:41 pm - 11:40 am
ONT
-
LHR
14h 59m1 stop
Delta Logo
12:30 pm - 9:05 pm
LHR
-
ONT
16h 35m1 stop
$598Delta
Wed, Feb 4 - Fri, Feb 27
Delta Logo
12:41 pm - 4:35 pm
ONT
-
LCY
19h 54m2 stops
Delta Logo
8:40 am - 9:05 pm
LCY
-
ONT
20h 25m2 stops
$661Delta
Sun, Mar 22 - Sat, Apr 4
Scandinavian Airlines Logo
1:20 pm - 4:35 pm
ONT
-
LCY
20h 15m2 stops
Scandinavian Airlines Logo
8:25 am - 10:34 pm
LCY
-
ONT
22h 09m2 stops
$746Scandinavian Airlines
Thu, Mar 5 - Thu, Mar 12
Multiple Airlines Logo
8:25 am - 10:55 am
ONT
-
LGW
18h 30m2 stops
Multiple Airlines Logo
11:55 am - 11:32 pm
LGW
-
ONT
18h 37m2 stops
$1,030Multiple Airlines
Mon, Feb 23 - Fri, Apr 10
Multiple Airlines Logo
12:02 pm - 10:30 pm
ONT
-
LGW
26h 28m2 stops
Multiple Airlines Logo
7:00 am - 11:59 pm
LGW
-
ONT
24h 59m2 stops
$1,257Multiple Airlines
Booking Insights

KAYAK's insights & trends for Ontario to London flights

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

How much is a round-trip flight from Ontario to London?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from Ontario to London departing in January.

What is the cheapest month to fly from Ontario to London?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Ontario to London, 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 Ontario to London is February, where tickets cost $654 (return) on average. On the other hand, the most expensive months are June and July, where the average cost of round-trip tickets is $1,054 and $986 respectively.

How far in advance should I book a flight from Ontario to London?

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from Ontario to London, 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 Ontario to London, you should book around 1 week before departure. For the absolute cheapest price, our data suggests you should book 15 weeks before departure.

Good to know

Low seasonFebruary
Cheapest flight$268
Best time to beat the crowds with an average 16% drop in price.
Most popular time to fly with an average 36% increase in price.
Flight from Ontario to London Gatwick Airport

When to book flights from Ontario to London

Are your dates flexible? Find out the best times to travel from Ontario to London 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 flights from Ontario to London

  • How can I get to the city center by public transport after my flight from Ontario to London?

    Upon arrival at London Heathrow Airport from Ontario, you can easily reach the city center using public transportation. Take the Heathrow Express train to Paddington Station, which operates every 15 minutes. From Paddington, you can transfer to the London Underground and take the Bakerloo Line or Circle Line to reach the city center.

  • Can I pre-book my seat on WestJet flights from Ontario to London?

    Yes, you can pre-book your seat on WestJet flights from Ontario to London. WestJet offers the option to select your preferred seat in advance, allowing you to secure your desired seating arrangement for a more comfortable journey. By accessing their online booking portal or contacting their customer service, you can make seat reservations according to your preferences and availability.

  • Which kid-friendly amenities does WestJet have on flights from Ontario to London?

    WestJet offers several kid-friendly amenities on flights from Ontario to London. These amenities include children's entertainment options such as movies, TV shows, and games suitable for different age groups. They also provide complimentary activity packs with coloring books, crayons, and puzzles to keep young travelers engaged during the flight.

  • What are the baggage restrictions when flying Virgin Atlantic from Ontario to London?

    The baggage restrictions when flying Virgin Atlantic from Ontario to London include a checked baggage allowance of two pieces weighing up to 50 lbs each in Economy class. Additionally, passengers are allowed one carry-on bag weighing up to 22 lbs and one personal item such as a laptop or handbag.

  • What is the cheapest flight from Ontario to London?

    In the last 3 days, the lowest price for a flight from Ontario to London was $268 for a one-way ticket and $579 for a round-trip.

  • Do I need a passport to fly between Ontario and London?

    A passport is required to fly from Ontario to London.

  • Which aircraft models fly most regularly from Ontario to London?

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

  • Which airline alliances offer flights from Ontario to London?

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

  • Which is the best airline for flights from Ontario to London, Delta or United Airlines?

    The two airlines most popular with KAYAK users for flights from Ontario to London are Delta and United Airlines. With an average price for the route of $752 and an overall rating of 7.9, Delta is the most popular choice. United Airlines is also a great choice for the route, with an average price of $851 and an overall rating of 7.4.

  • How does KAYAK find such low prices on flights from Ontario to London?

    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 Ontario to London.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Ontario to London?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to London from Ontario 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 Ontario to London?

    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 with an airline and back to Ontario with another airline.

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

    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 from Ontario 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 Ontario to London

  • Common layover options for Air Canada flights from Ontario (ONT) to London (LON) may include stopovers in major hub cities such as Toronto, Montreal, or Ottawa. These layovers often provide convenient connections for passengers, allowing them to change planes and continue their journey to London.
  • Additionally, Air Canada offers a special food service called "Chef's Menu" on its flights from Ontario to London. Passengers can enjoy a delectable selection of culinary delights prepared by renowned chefs. The menu features a range of gourmet dishes using fresh, locally sourced ingredients, ensuring a delightful dining experience in the skies. From appetizers to main courses and desserts, Air Canada's Chef's Menu promises to satisfy the taste buds of travelers throughout their journey.
  • Air Canada offers a variety of in-flight entertainment options on its flights from Ontario to London. Passengers can enjoy a selection of movies, TV shows, and music, with a wide range of genres to choose from. Additionally, the airline provides personal screens with touch controls, offering a seamless and enjoyable viewing experience.
  • WestJet assists passengers with disabilities traveling from Ontario to London. They offer wheelchair assistance, accessible seating options, and priority boarding. Passengers can request special services such as mobility aids or medical equipment during their journey. WestJet's trained staff is available to ensure a comfortable and safe travel experience for passengers with disabilities, addressing their specific needs and providing necessary support throughout the journey.
  • You can change your seat when flying with WestJet from Ontario to London. Seat changes are subject to availability, and you can make the change either during the booking process or by accessing your reservation online. Alternatively, you can contact WestJet's customer service for assistance with seat changes.

Reviews of the top 5 airlines serving from Ontario to London

 
See real verified KAYAK customer reviews for airlines flying from Ontario 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 Ontario to London? 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.
7.9
DeltaOverall score based on 8035 reviews
7.9Comfort
7.2Food
7.8Entertainment
8.1Boarding
8.5Crew
Airline reviews

The flight was delayed for about 2 hrs. Other than it, it was good.

8.0 ExcellentWen, Dec 2025
LAX - MSY
Read more Delta reviews

The flight was delayed for about 2 hrs. Other than it, it was good.

I am extremely disappointed that delta internal pilot manuals now refer to the Gulf of Mexico as the “gulf of America”. You can bow down to the Orange turd on your own. I will never fly delta again

No lunch on a x-country flight scheduled for 10:50 am departure, arrived 5+ hrs later. That requires a black box label before you pay for the tickets. Worst, when I checked in online, it's specifically said that lunch was served on his flight for economy Plus passengers.

Our flight from SFO to MSP was right on time on 11/15/2025. No delays. As we approached MSP at about 8 pm, we circled in the air until 8:40 pm so I don't call that efficient for MSP. I think the captain should announce the delay and why. (as if we all don't know that we are just circling around the area, slowing down, speeding up, slowing down.) Thank you. Marilyn Fischer

Plenty of leg room, temperature was great and staff was excellent. Would do it more often.

Staff were friendly and happy. Delta could make sure passengers that don't have the app know of changes. Without Kayak I would not have known about the change of gate or the delay. Kayak was faster to notify me.

The flight used a B767 with a very old interior from before 2014. The entertainment system did not work at all during the flight despite attempts to reset the system. It was like they flew this route just to be competitive.

Delayed flight (1hour) plus a long layover after an overnight flight with no backup plane available.

Passengers need to check in big baggage instead of bringing on the plane. That cause inconvenience for everyone. Otherwise flight was good.

Flight delayed for two and half hours and then canceled altogether due to mechanical issues. No mechanic onsite to fix so had to send one from LAX.

Some flight attendants were great others were cranky. Seats were very tight and sitting on an aisle was very hard as the carts and people walking constantly bumped shoulder and arm.

It was great with United overall except for two things. 1) It was a 5-hour flight and we were with kids, so we were asking for extra snacks. They were extremely reticent to dole them out even though there wasn't any meal and the kids were starting to hit their limit towards the end. 2) Baggage didn't arrive until 80 minutes after we landed.

I’m so sorry, I can’t remember her name, I believe it was Dimpti. She was stellar, also a mature Asian flight attendant, lots of flowers in her hair, just as amazing! But literally the crew was AWESOME . Only downside is there weren’t any charging outlets. Maybe I needed to ask a flight attendant , but it would’ve been nice to have one easily accessible.

I boarded flight UA#1318 at Sacramento International Airport going back to Houston TX. The flight was scheduled at 5:10am. I was able to check in virtually using the United Airlines app. When I entered the airport, there was no one outside assisting with checked bags as it was for Delta Airlines. Immediately upon entering, there was a LONG, EXTREMELY LONG line to the kiosks to get boarding passes. I stand in line to get boarding passes then had to move to ANOTHER EXTREMELY LONG line to get my bags checked in. While standing in this line, we noticed an agent taking customers to 3 at a time to her station to check their bags in. Lucky for me, she called me back, checked my bags for me and I was on my way. I then encountered another long line at the TSA check and to avoid I ending up having to sign up for CLEAR to bypass it. So glad, I did.,...Both of my flights were great with no issues, butthe check in progress at Bush Airport was so much smoother. Check-in at SMF airport needs to be anaylzed and corrected. Do better United, I know you can....thanks

Pushed back only to get deplaned due to a tire damaged by ground crew. They did at least go pretty fast. The bathrooms should be banned under the Geneva convention. No room to even sit straight on the toilet. The under-seat entertainment units block what little leg room there is.

United airlines has the best customer experience from booking to arrival. I always fly United airlines. The mileage program is excellent

from SFO-> FRA flight, AVML meal was significantly less compared to regular meal, especially no Desert, no Bread, no sides.

This was an older airplane. The cabin was constantly warm to hot throughout the 10 hour flight and there were no vents to personalize air flow. Also since it was an older plane, the material and comfort of the chairs were very uncomfortable. I left my flight with major soreness on my tailbone.

Older aircraft, no meal, only food was for purchase. Not impressed United.

Not pleasant trip cross country when the entertainment and WiFi system not working. No entertainment for entirety of route. Staff was rather nonchalant in that they dismissed the problem due to age of plane. It would have been nice to know this up front so I could have come prepared to read or download movies before boarding Coincidentally or not, there was a similar issue with the entertainment system on my previous flight I took on my fist leg of the trip. There are no seat TVs, so you must rely on the app when it works. United can do better. Also, what use it it to pay for boarding group 2 when half of the passengers are in the same line as you?

The flight was on time and arrived early. The crew were friendly and helpful.

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

Pathetic check in experience at JFK. Everything is self check in. Not enough staff present to help with when the check in process or the kiosk gets stuck. Staff present not welcoming or pleasant at all. On the other hand the NY based flight crew was great. Courteous and friendly throughout the flight. Special meals leave a lot to be desired. Kids meals should be made available when kids are flying and same goes for special kids meals too.

The chair cushions may need an upgrade. I have been noticing they are so worn out, thin so you’d sit in a dip 😄. Other than that, all was an enjoyable trip. Thanks AA!

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.

The staff was very nice and helpful. Some of the best crew I have met.

Suddenly, I don't find my flight back on the app Help Ticket 0757345716866 Hoeflich Flight back Sunday ib5333 Ib2629 Ib4268

Was all good.l including a sofdrink. AA improved significantly. There was no entertainment.

I've taken British Airways before and it has been great. On this trip to Spain and Portugal we had two BA flights. On both flights we were taken by bus from the terminal out to the plane on the tarmac. There were many older folks on these flights, and to ask people in their 70s to lug their carry-on and personal items up the long mobile staircase to the plane entrance, is very disturbing. I won't be taking British Airways in the future. Many people on these flights were very unhappy.

The food on the flight was of marginal quality. Small bits of chicken, instant mashed potatoes and some carrots. The rolls were very dry, nearly inedible. The seats were quite small and didn’t allow for any shifting of position during the flight. There was limited leg room.0

The seats are so small that you can barely move at all. Don't try to eat with utensils in your seat either - you will elbow your neighbor in the face. Miserably small and I swear they are shrinking every time I fly. Food was meh (per usual), but at least there is free alcohol on an overseas flight. Doesn't make up for sitting in a torture chamber while hurtling through the air with hundreds of fussy people, but it's something. Entertainment options (movies, shows) are okay, nothing special, but at least there are screens, because most of the seats in these large planes do not have adjustable lighting - or air control - that you can get to, it's too high to reach - which makes reading impossible. Zero stars, AA.

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

I travelled in business class and was disappointed by lack of service, curt and borderline rude time of the crew and to top it off, all of my luggage was delayed. It was like pulling teeth to even report the missing luggage and recover it the next day from the airport.

Boarding was poor. All groups called immediately one after the other resulting in a long queue in the jetty/jet bridge. Seats were very hard and and did not recline on a 4.5 hour flight. No food was available. Plane was cold. There was no entertainment.

The cramped seats are cruel and unusual punishment and may violate the Geneva code.

Check in was was and the agent was very friendly and helpful The lounge was nice...boarding was straight from the lounge Everything worked at our seats, and video entertainment was good ..food was mediocre

The flight was excellent in World Travellor plus. Well worth the extra money. Boarding at Phoenix was the usual poorly organized event. Very stressful.

Although business class, the seating was really cramped. The food was so so.

Smooth trip no turbulence which is always a bonus for me lol! In cattle class so an element of being a bit squished (but not as bad as other shorter haul airlines) smaller plane than the one we flew out on and entertainment system wasn’t as modern but still definitely passed the time. Lovely crew x

Everything you need to know for your flight from Ontario to London

Information on your arrival and departure airports