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Cheap flights from London Heathrow Airport to Ontario from £335

LHR — ONT
5 Dec — 12 Dec1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from Heathrow to Ontario

Enter your travel dates to find the best prices.

Cheapest flights from Heathrow to Ontario

Thu 12/1114:45 -
1 stop16h 21m
Fri 4/1206:00 -
1 stop22h 20m
Deal found 4/11£419
Mon 9/1114:45 -
1 stop28h 33m
Tue 24/1120:59 -
1 stop31h 21m
Deal found 1/11£421
Sat 21/1114:45 -
1 stop16h 46m
Mon 7/1206:00 -
1 stop22h 20m
Deal found 3/11£422
Mon 7/1214:45 -
1 stop16h 14m
Wed 23/1220:59 -
1 stop31h 21m
Deal found 3/11£422
Sat 21/1114:45 -
1 stop16h 46m
Thu 26/1111:55 -
1 stop16h 25m
Deal found 5/11£423
Tue 10/1114:45 -
1 stop28h 33m
Tue 17/1106:00 -
1 stop22h 20m
Deal found 2/11£424
Mon 7/1214:45 -
1 stop33h 20m
Tue 12/111:34 -
1 stop16h 46m
Deal found 3/11£425
Tue 17/1114:45 -
1 stop35h 32m
Thu 3/1211:57 -
1 stop16h 23m
Deal found 31/10£425
Sun 8/1114:45 -
1 stop32h 28m
Sun 22/1106:00 -
1 stop22h 20m
Deal found 1/11£426
Wed 11/1114:45 -
1 stop35h 32m
Sun 6/1206:00 -
1 stop22h 20m
Deal found 4/11£428
Sun 22/1114:45 -
1 stop16h 46m
Thu 24/1206:00 -
1 stop22h 20m
Deal found 4/11£428

Find flight deals from Heathrow to Ontario

Round-trip from

£421

One-way from

£335

Popular in

July

Cheapest in

January

Average price

£514
Alaska Airlines
  • Alaska Airlines
  • 17/11-27/11
  • 2 total stops
  • 54h 48m total
  • London to Ontario
Search Deals
11/12-31/12
  • 11/12-31/12
  • 3 total stops
  • 45h 28m total
  • London to Ontario
Search Deals
Highest demand for flights based on searches. 12% potential increase in price (£54 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease (£8 potential savings vs. average return price).
Search Deals
Average for round-trip flights in November 2026
Search Deals

Cheapflights Fare Finder

 
Use the filters below to find and compare flights from London Heathrow Airport to Ontario that are best for you.

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Route

Depart

Return

Price

Cheapest return flight

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Sun 14/3

14:45-22:39

1 stop14h 54m

Ontario

Wed 31/12

00:00-09:00

Nonstop0h 00m

£359

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Tue 16/2

14:45-22:39

1 stop15h 54m

Ontario

Wed 24/2

12:00-12:20

1 stop16h 20m

£438

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Wed 18/11

14:45-15:13

1 stop32h 28m

Ontario

Wed 2/12

06:00-12:20

1 stop22h 20m

£439

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Sun 17/1

07:30-22:30

2 stops23h 00m

Ontario

Wed 31/12

00:00-09:00

Nonstop0h 00m

£448

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Tue 8/12

14:45-11:13

1 stop28h 28m

Ontario

Mon 4/1

20:59-12:20

1 stop31h 21m

£456

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Tue 30/3

21:25-22:39

2 stops33h 14m

Ontario

Wed 31/12

00:00-09:00

Nonstop0h 00m

£542

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Sun 28/3

10:50-17:17

1 stop14h 27m

Ontario

Thu 8/4

17:47-15:35

1 stop13h 48m

£611

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Fri 26/2

07:30-21:17

2 stops21h 47m

Ontario

Tue 2/3

06:00-07:40

1 stop17h 40m

£614

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 19/11

14:45-23:06

1 stop16h 21m

Ontario

Fri 11/12

17:01-12:20

1 stop35h 19m

£783

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 7/1

14:35-22:15

1 stop15h 40m

Ontario

Tue 19/1

16:19-13:35

1 stop13h 16m

£793

Flights are sorted by cheapest return flights first.

Deals found on 5/11

Showing 1-10 of 23 resultsSorted by cheapest first
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2
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Best time to book a flight from Heathrow to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from Heathrow with our price prediction graph.
Estimated return price

Cheapflights Insights

Everything you need to know about your flight from London Heathrow Airport to Ontario

What is the cheapest month to book a flight from London Heathrow Airport to Ontario?

Currently, January is the cheapest month in which you can book a flight from London Heathrow Airport to Ontario (average of £410). Flying from London Heathrow Airport to Ontario in July is currently the most expensive (average of £612). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

How much does it cost for a return flight from London Heathrow Airport to Ontario?

Airfare is below average for this route at the moment.

London Heathrow Airport to Ontario flights typically cost between £466 and £531 in November.
The cheapest return price found within the last 5 days was £421 on Alaska Airlines (17 Nov–27 Nov).

Reviews of airlines servicing Ontario

Read reviews from past customers who have flown with Alaska Airlines,Virgin Atlantic, andUnited Airlines from London Heathrow Airport to Ontario. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
7.9
Good
13,142 reviews
Check prices

Comfort

7.8

Overall

7.9

Boarding

8.1

Crew

8.5

Food

7.0

Entertainment

7.0

Reviews

1 / 20
2.0
Mediocre

Chris,Aug 2026

GEG - SFO

Our flight was delayed multiple times over the course of the day for a total of almost ten hours. It was supposed to be a two-hour flight from San Francisco to Spokane. It turned into a nightmare of waiting all day in the airport, not knowing whether we would fly or not, whether we would miss my son's wedding and lose the expenses already incurred for car rental and accommodations. The Alaska staff seemed clueless and never gave us any convincing or definitive information. The airline offered food vouchers and discounts on future flights to make up for the trouble. However, the information about these concessions was not timely, nor were the vouchers themselves very useful. We were a family group of four people. The airline decided to give us one food voucher for $96, which is barely enough for four to get a sandwich and a drink each. Only by persistently addressing the airport food retailers were we able to get anything at all. Then, taking the exact opposite approach, the airline sent me, the original purchaser of all four tickets and the only email account they had, four vouchers for $150 each in the names of each of the four passengers. So, any one of us could get a discount on a future flight with Alaska in that amount. But I originally paid for all the tickets. It makes no sense, except to suggest that Alaska chooses the way to distribute vouchers that seems most likely to minimize the probability that they will be utilized. In my opinion, I should be offered a total refund for the ordeal we were forced to endure or at least a discount voucher for the entire $600.
Alaska Airlines
7.9
Good
13,142 reviews
Alaska Airlines
7.9
Good
13,142 reviews
Check prices

Comfort

7.8

Overall

7.9

Boarding

8.1

Crew

8.5

Food

7.0

Entertainment

7.0

Reviews

1 / 20
2.0
Mediocre

Chris,Aug 2026

GEG - SFO

Our flight was delayed multiple times over the course of the day for a total of almost ten hours. It was supposed to be a two-hour flight from San Francisco to Spokane. It turned into a nightmare of waiting all day in the airport, not knowing whether we would fly or not, whether we would miss my son's wedding and lose the expenses already incurred for car rental and accommodations. The Alaska staff seemed clueless and never gave us any convincing or definitive information. The airline offered food vouchers and discounts on future flights to make up for the trouble. However, the information about these concessions was not timely, nor were the vouchers themselves very useful. We were a family group of four people. The airline decided to give us one food voucher for $96, which is barely enough for four to get a sandwich and a drink each. Only by persistently addressing the airport food retailers were we able to get anything at all. Then, taking the exact opposite approach, the airline sent me, the original purchaser of all four tickets and the only email account they had, four vouchers for $150 each in the names of each of the four passengers. So, any one of us could get a discount on a future flight with Alaska in that amount. But I originally paid for all the tickets. It makes no sense, except to suggest that Alaska chooses the way to distribute vouchers that seems most likely to minimize the probability that they will be utilized. In my opinion, I should be offered a total refund for the ordeal we were forced to endure or at least a discount voucher for the entire $600.
Virgin Atlantic
7.5
Good
697 reviews
Alaska Airlines
7.9
Good
13,142 reviews
Check prices

Comfort

7.8

Overall

7.9

Boarding

8.1

Crew

8.5

Food

7.0

Entertainment

7.0

Reviews

1 / 20
2.0
Mediocre

Chris,Aug 2026

GEG - SFO

Our flight was delayed multiple times over the course of the day for a total of almost ten hours. It was supposed to be a two-hour flight from San Francisco to Spokane. It turned into a nightmare of waiting all day in the airport, not knowing whether we would fly or not, whether we would miss my son's wedding and lose the expenses already incurred for car rental and accommodations. The Alaska staff seemed clueless and never gave us any convincing or definitive information. The airline offered food vouchers and discounts on future flights to make up for the trouble. However, the information about these concessions was not timely, nor were the vouchers themselves very useful. We were a family group of four people. The airline decided to give us one food voucher for $96, which is barely enough for four to get a sandwich and a drink each. Only by persistently addressing the airport food retailers were we able to get anything at all. Then, taking the exact opposite approach, the airline sent me, the original purchaser of all four tickets and the only email account they had, four vouchers for $150 each in the names of each of the four passengers. So, any one of us could get a discount on a future flight with Alaska in that amount. But I originally paid for all the tickets. It makes no sense, except to suggest that Alaska chooses the way to distribute vouchers that seems most likely to minimize the probability that they will be utilized. In my opinion, I should be offered a total refund for the ordeal we were forced to endure or at least a discount voucher for the entire $600.
United Airlines
7.3
Good
10,458 reviews
Alaska Airlines
7.9
Good
13,142 reviews
Check prices

Comfort

7.8

Overall

7.9

Boarding

8.1

Crew

8.5

Food

7.0

Entertainment

7.0

Reviews

1 / 20
2.0
Mediocre

Chris,Aug 2026

GEG - SFO

Our flight was delayed multiple times over the course of the day for a total of almost ten hours. It was supposed to be a two-hour flight from San Francisco to Spokane. It turned into a nightmare of waiting all day in the airport, not knowing whether we would fly or not, whether we would miss my son's wedding and lose the expenses already incurred for car rental and accommodations. The Alaska staff seemed clueless and never gave us any convincing or definitive information. The airline offered food vouchers and discounts on future flights to make up for the trouble. However, the information about these concessions was not timely, nor were the vouchers themselves very useful. We were a family group of four people. The airline decided to give us one food voucher for $96, which is barely enough for four to get a sandwich and a drink each. Only by persistently addressing the airport food retailers were we able to get anything at all. Then, taking the exact opposite approach, the airline sent me, the original purchaser of all four tickets and the only email account they had, four vouchers for $150 each in the names of each of the four passengers. So, any one of us could get a discount on a future flight with Alaska in that amount. But I originally paid for all the tickets. It makes no sense, except to suggest that Alaska chooses the way to distribute vouchers that seems most likely to minimize the probability that they will be utilized. In my opinion, I should be offered a total refund for the ordeal we were forced to endure or at least a discount voucher for the entire $600.
British Airways
6.7
Okay
8,282 reviews
Alaska Airlines
7.9
Good
13,142 reviews
Check prices

Comfort

7.8

Overall

7.9

Boarding

8.1

Crew

8.5

Food

7.0

Entertainment

7.0

Reviews

1 / 20
2.0
Mediocre

Chris,Aug 2026

GEG - SFO

Our flight was delayed multiple times over the course of the day for a total of almost ten hours. It was supposed to be a two-hour flight from San Francisco to Spokane. It turned into a nightmare of waiting all day in the airport, not knowing whether we would fly or not, whether we would miss my son's wedding and lose the expenses already incurred for car rental and accommodations. The Alaska staff seemed clueless and never gave us any convincing or definitive information. The airline offered food vouchers and discounts on future flights to make up for the trouble. However, the information about these concessions was not timely, nor were the vouchers themselves very useful. We were a family group of four people. The airline decided to give us one food voucher for $96, which is barely enough for four to get a sandwich and a drink each. Only by persistently addressing the airport food retailers were we able to get anything at all. Then, taking the exact opposite approach, the airline sent me, the original purchaser of all four tickets and the only email account they had, four vouchers for $150 each in the names of each of the four passengers. So, any one of us could get a discount on a future flight with Alaska in that amount. But I originally paid for all the tickets. It makes no sense, except to suggest that Alaska chooses the way to distribute vouchers that seems most likely to minimize the probability that they will be utilized. In my opinion, I should be offered a total refund for the ordeal we were forced to endure or at least a discount voucher for the entire $600.

Related info for your journey

  • What airport do you fly into for flights to Ontario from London Heathrow?

    If you book a flight to Ontario from London Heathrow, you will be flying to Ontario, which is the city’s only airport. Ontario (ONT) is located 3.1 mi from the center of Ontario. There are 0 flights from London Heathrow to Ontario per day from 4 different airlines.

  • How long is the flight from London Heathrow Airport to Ontario?

    Alaska Airlines, Delta, and United Airlines can get you from London Heathrow Airport to Ontario in just under 14h 27m. Your travel time can differ by up to 7h 20m. The distance between London Heathrow Airport and Ontario is about 5407 mi. This flight may include one or multiple stops.

  • What are the cheapest airlines flying from London Heathrow Airport to Ontario round-trip?

    Currently priced at £371, United Airlines will fly you from London Heathrow Airport to Ontario and back. In addition to United Airlines, many other airlines offer competitively priced options for your trip. Search Cheapflights for deals from Virgin Atlantic and British Airways - these airlines can fly you to your destination from £373 and £404, respectively. Users have found that United Airlines is 27% cheaper than the other options available to this destination.

  • Can I find deals for flights from Heathrow to Ontario that include hotel bookings?

    Yes. In addition to deals on Heathrow to Ontario flights, Cheapflights offers holiday packages that include both flights and hotel.

  • How can I find direct flights from Heathrow to Ontario?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Heathrow to Ontario.

  • Can I find deals for business class flights from Heathrow to Ontario?

    Yes. Cheapflights offers flight deals from Heathrow to Ontario by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from London Heathrow Airport to Ontario?

    Currently, January is the cheapest month in which you can book a flight from London Heathrow Airport to Ontario (average of £410). Flying from London Heathrow Airport to Ontario in July is currently the most expensive (average of £612). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

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Top 4 airlines flying from Heathrow to Ontario

AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest£371Average£514FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
Virgin AtlanticCheapest£373Average£509FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
British AirwaysCheapest£404Average£514FlexibilityNo cancel feeOn-time70%
Search British Airways flights
Alaska AirlinesCheapest£424Average£441FlexibilityNo cancel feeOn-time75%
Search Alaska Airlines flights

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Yes, Cheapflights offers price alerts on Heathrow to Ontario flights so you can book your travel at the perfect time. Price Alerts can be enabled by clicking the bell icon next to the flight deals above and providing your email address where you want to receive the alerts.

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