Cheap flights from Ontario to London from $283
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Ontario to London departing on 10/13. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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Delta flights from Ontario to London Heathrow Airport
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Virgin Atlantic flights from Ontario to London Heathrow Airport
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How to get the cheapest flight ticket from Ontario to London Heathrow Airport
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the cheapest month to fly to London Heathrow Airport?
The month of March is, on average, the cheapest month to fly to London Heathrow Airport from Ontario, with most prices found around $669. If you’re not able to fly to London Heathrow Airport in March, then October is your next best option. Flight prices from Ontario to London Heathrow Airport during October average around $677.
What is the cheapest day to depart on your flight to London Heathrow Airport?
Our data shows that Wednesday is the least expensive day to fly to London Heathrow Airport. Tickets to fly out on this day can be as low as $789. The most expensive day to fly to London Heathrow Airport is Saturday, with ticket prices averaging around $917.
What is the cheapest time of day to depart on your flight to London Heathrow Airport?
According to our data, the cheapest time of day to fly to London Heathrow Airport is in the morning. momondo users have found flights departing from Ontario to London Heathrow Airport in the morning for as low as $755. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights in the evening are often more expensive with an average ticket price of $853.
How far in advance should I book a flight to London Heathrow Airport?
You are more likely to see cheaper flights to London Heathrow Airport from Ontario when booking weeks ahead of your departure date. In general, you can expect to find flights to London Heathrow Airport for around $842 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to London Heathrow Airport from Ontario for as low as $608 on momondo.
What is the cheapest airline that flies from Ontario to London Heathrow?
JetBlue, British Airways, and KLM are the most popular carriers operating from Ontario to London Heathrow
What airlines fly to London Heathrow Airport?
British Airways, Iberia and Delta are the top three most popular airlines that fly to London Heathrow Airport from Ontario according to our data. British Airways is the first choice among our users, with 47% of people opting to fly with this airline when traveling to London Heathrow Airport. Keep in mind that there are 20 different airlines that fly to London Heathrow Airport on a routine basis, so you have a few additional options to choose from.
When to book flights from Ontario to London Heathrow Airport
Cheap Ontario to London Heathrow Airport (ONT to LHR) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Ontario to London Heathrow Airport
How far is Ontario to London Heathrow by plane?
The straight-line distance from Ontario to London Heathrow is 5408.1 mi. Typically, this will take 12h 00m by plane in normal conditions.
When did momondo last update prices for flights from Ontario Airport to London Heathrow Airport?
Prices for flights from Ontario Airport to London Heathrow Airport are updated daily.
How many operators does momondo search for flights from Ontario Airport to London Heathrow Airport?
As of June 2025, there are 7 operators available to choose from for flights from Ontario Airport to London Heathrow Airport.
How old do you have to be to fly from Ontario Airport to London Heathrow Airport?
The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Ontario Airport to London Heathrow Airport.
What documentation or ID do you need to fly to London Heathrow Airport?
The necessary travel and health documents for your London Heathrow Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.
What is the most popular airline from Ontario to London Heathrow Airport?
Based on momondo bookings for flights between Ontario and London Heathrow Airport, the leading airline is United Airlines, making up 26% of the total bookings. Other popular airlines include American Airlines with 24%, British Airways with 22%, and Delta with 13%.
Best airlines flying from Ontario to London Heathrow Airport
Compare and see reviews for airlines that fly from Ontario to London Heathrow Airport with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $454 | Free Cancellation | Rating 7.4 653 reviews | |||
| PriceFrom $582 | Free Cancellation | Rating 7.0 2,778 reviews | |||
| PriceFrom $599 | Free Cancellation | Rating 8.0 7,964 reviews | |||
| PriceFrom $608 | Free Cancellation | Rating 7.8 1,364 reviews | |||
| PriceFrom $633 | Free Cancellation | Rating 7.4 8,810 reviews | |||
| PriceFrom $648 | Free Cancellation | Rating 6.6 7,031 reviews | |||
| PriceFrom $648 | Free Cancellation | Rating 7.2 10,000 reviews |
Traveling to a place near London?
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Why should I use momondo to find a flight deal from Ontario to London?
Finding the right flight to London from Ontario is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to London quick and easy, saving you time and money.
Can I find flights from Ontario to London with flexible booking policies on momondo?
Yes. momondo allows you to filter the results for Ontario to London flights to just show those with flexible booking policies.
How can momondo help me find flights from Ontario to London?
momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Ontario to London.
I’m not ready to book a flight from Ontario to London right now. Can momondo alert me if prices change?
Yes momondo offers price alerts on flights to London from Ontario. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.