$352 Find Cheap Flights from the United Kingdom to Ontario

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight to Ontario departing on 2/6. 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 Ontario

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

Cheapest round-trip
$394
Overall average: $839
Delta
Wed 4/15Mon 4/20
LHR - ONT • 1 stop
Cheapest one-way
$352
Multiple Airlines
Fri 2/6
LGW - ONT • 2 stops
When to travel
January
Cheapest • 23% price drop
November
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Ontario!
Flight Deals
Booking Insights
Flight Deals

Cheap Flights from the United Kingdom to Ontario

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

Wed, Apr 15 - Mon, Apr 20
Delta Logo
9:20 am - 6:28 pm
LHR
-
ONT
17h 08m1 stop
Delta Logo
11:53 am - 2:15 pm
ONT
-
LHR
18h 22m1 stop
$394Delta
Sat, Apr 11 - Sun, Apr 19
American Airlines Logo
8:20 am - 5:45 pm
LHR
-
ONT
17h 25m1 stop
American Airlines Logo
3:05 pm - 2:25 pm
ONT
-
LHR
15h 20m1 stop
$411American Airlines
Fri, Apr 10 - Sun, Apr 19
American Airlines Logo
8:20 am - 5:45 pm
LHR
-
ONT
17h 25m1 stop
American Airlines Logo
12:55 pm - 2:25 pm
ONT
-
LHR
17h 30m1 stop
$417American Airlines
Thu, Feb 5 - Thu, Feb 12
British Airways Logo
7:30 am - 10:48 pm
LHR
-
ONT
23h 18m2 stops
British Airways Logo
10:59 am - 10:00 am
ONT
-
LHR
15h 01m1 stop
$484British Airways
Mon, Jan 12 - Tue, Mar 31
Virgin Atlantic Logo
8:25 pm - 4:12 pm
LHR
-
ONT
27h 47m2 stops
Virgin Atlantic Logo
6:00 am - 12:10 pm
ONT
-
LHR
22h 10m1 stop
$494Virgin Atlantic
Tue, Mar 10 - Thu, Mar 19
British Airways Logo
9:50 am - 10:07 pm
GLA
-
ONT
19h 17m2 stops
British Airways Logo
5:02 pm - 4:40 pm
ONT
-
GLA
16h 38m2 stops
$599British Airways
Fri, Mar 6 - Tue, Mar 10
United Airlines Logo
1:45 pm - 10:57 pm
BHX
-
ONT
17h 12m2 stops
United Airlines Logo
6:00 am - 12:35 pm
ONT
-
BHX
23h 35m2 stops
$659United Airlines
Fri, Mar 6 - Tue, Mar 10
United Airlines Logo
8:45 am - 10:25 pm
BHX
-
ONT
45h 40m2 stops
United Airlines Logo
6:37 pm - 12:45 pm
ONT
-
BHX
35h 08m2 stops
$661United Airlines
Thu, Feb 5 - Thu, Feb 12
Iberia Logo
7:50 am - 10:48 pm
LCY
-
ONT
22h 58m2 stops
Iberia Logo
7:10 am - 8:50 am
ONT
-
LCY
17h 40m2 stops
$728Iberia
Mon, Jan 19 - Mon, Feb 9
Iberia Logo
7:40 pm - 10:08 am
LGW
-
ONT
22h 28m2 stops
Iberia Logo
10:58 am - 7:00 pm
ONT
-
LGW
24h 02m2 stops
$751Iberia
Booking Insights

KAYAK's insights & trends for flights to Ontario

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

What is the cheapest month to fly to Ontario?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for flights to Ontario, 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 to Ontario is November, where tickets cost $615 on average for one-way flights. On the other hand, the most expensive months are December and July, where the average cost of tickets from the United Kingdom is $1,315 and $1,231 respectively. For return trips, the best month to travel is January with an average price of $551.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights to Ontario, 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, you should book around 1 week before departure. For the absolute cheapest price, our data suggests you should book 75 days before departure.

Find deals

Good to know

Low seasonJanuary
Cheapest flight$352
Best time to beat the crowds with an average 10% drop in price.
Most popular time to fly and prices are also 21% lower on average.
Flight from London Gatwick Airport to Ontario

FAQs - booking Ontario flights

  • How far is Ontario Airport from central Ontario?

    You’ll need to travel 3 miles to reach the Ontario city center from Ontario Airport.

  • What is the name of Ontario’s airport?

    All flights to Ontario land at Ontario Airport. The airport code is ONT,and it can also be referred to as Ontario or Ontario Intl.

  • What is the cheapest day to fly to Ontario?

    Based on KAYAK data, the cheapest day to fly to Ontario is Tuesday where tickets can be as cheap as $602. On the other hand, the most expensive day to fly is Saturday, where prices are $1,757 on average.

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

    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 to Ontario.

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

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

    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 Ontario with an airline and back with another airline.

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

    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 Ontario up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • What is the cheapest time of day to fly to Ontario?

    The cheapest time of day to fly to Ontario is generally in the evening, when flights cost $602 on average. The most expensive time of day to fly to Ontario is generally in the afternoon, which is peak travel time and where the average cost of a ticket is $814.

  • How many direct flights to Ontario are there each week?

    Each week there are around 853 direct flights from within United Kingdom to Ontario. The most common day for departures is Monday, with 17% of flights taking off on this day.

Top tips for finding cheap flights to Ontario

  • Enter your preferred departure airport and travel dates into the search form above to unlock the latest Ontario flight deals.

Reviews of the top airline flying from the United Kingdom to Ontario

 
See real verified KAYAK customer reviews for airlines flying to Ontario. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline from the United Kingdom to Ontario. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with to Ontario? 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 9110 reviews
7.1Entertainment
6.6Food
8.1Crew
7.3Comfort
7.7Boarding
Airline reviews

Flight was late - I was downgraded from first class to coach

2.0 MediocreMukund, Dec 2025
DEN - SFO
Read more United Airlines reviews

Flight was late - I was downgraded from first class to coach

Movie selection is good. Crew did not understand mileage program and were no help. Sick later. Food?

United needs to step up their game. Delayed flight leaving Seattle, San Francisco. Older aircraft, not very comfortable.

The flight attendants were very rude, beyond comprehension. I took a business class from London to SFO for the first time on United. When I asked for a second piece of bread during dinner, the serving attendant threw a 3rd bread on my plate and said, “here. You can have this one too”! I couldn’t believe the rudeness of the attendant. Most all attendants were very rude, unhelpful, sing the food was absolutely disgusting. Never fly United internationally in business class. My flight back to SFO was a nightmare!!

Plane boarded early a quickly, was mostly full. We left close to on time. And landed early.

7 hours delayed due to operational issues on United’s end. Basically laziness.

Flight from Rome to SFO was excellent compared To our flight to Europe from SFO. The food was much tastier. You can see how UNITED is skimping, though. Instead of getting something mid flight you had to ask for it. It was not automatically served. There was a cookie at the end of the arrival meal, for example that tasted like it just came out of a box. They used to serve a little container of nuts, now … a tiny container of nuts, mixed with pretzels. This was business class that you really have to pay for! But this is minor complaints compared to the overall. My major complaint is the position of the even numbered seats by the windows. You have to turn around to see your window & the positioning as some other controls are harder to get at. This is compared to the odd number seat that are perfectly aligned.

The food quality sucks. One must starve if they do not eat flesh Or wheat based products Some variety would be expected. The trivial amount of snacks and or food is inhumane

Flight was timely, relatively comfortable, with decent entertainment and food served. Only problem encountered was with the free messaging which I highly appreciate, but it did not work from iphone to non-iphones.

The internet service I paid for didn’t work at all and the flight crew was not very friendly.

Everything you need to know for your flight to Ontario

Information on the airport you'll fly into in Ontario

Ontario (ONT)