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Cheap flights from the United Kingdom to Ontario from £350

LHR — ONT
24 Oct — 31 Oct1
1 adult
1 adult, Economy, 0 bags

Cheap flight deals from United Kingdom to Ontario

Enter your travel dates to find the best prices.

Cheapest flights from United Kingdom to Ontario

Mon 16/1109:00 -
2 stops21h 48m
Sun 29/1105:00 -
1 stop20h 40m
Deal found 21/9£379
Wed 21/1007:25 -
2 stops23h 26m
Mon 2/1105:00 -
2 stops16h 55m
Deal found 23/9£384
Fri 6/1107:30 -
2 stops21h 21m
Mon 16/1109:25 -
1 stop17h 50m
Deal found 23/9£385
Fri 6/1109:30 -
2 stops21h 18m
Fri 13/1106:00 -
1 stop17h 25m
Deal found 22/9£386
Wed 4/1109:30 -
2 stops18h 45m
Wed 11/1105:00 -
1 stop20h 40m
Deal found 19/9£386
Wed 4/1108:40 -
2 stops45h 31m
Wed 11/1112:18 -
2 stops34h 02m
Deal found 19/9£393
Fri 6/1115:45 -
2 stops38h 58m
Fri 13/1113:15 -
2 stops33h 05m
Deal found 22/9£398
Sat 7/1107:30 -
2 stops21h 21m
Sat 14/1105:00 -
2 stops16h 55m
Deal found 23/9£402
Thu 5/1109:30 -
2 stops18h 45m
Thu 12/1105:00 -
2 stops16h 55m
Deal found 21/9£404
Sat 26/909:30 -
2 stops19h 28m
Fri 9/1013:52 -
1 stop13h 18m
Deal found 19/9£404
Sat 17/1017:45 -
1 stop36h 58m
Sat 24/1013:35 -
2 stops35h 10m
Deal found 19/9£406
Tue 20/1018:35 -
2 stops37h 20m
Tue 27/1013:35 -
2 stops23h 35m
Deal found 22/9£407

Find flight deals from United Kingdom to Ontario

Round-trip from

£379

One-way from

£350

Popular in

December

Cheapest in

February

Average price

£470
United Airlines
  • United Airlines
  • 13/11-28/11
  • 3 total stops
  • 42h 28m total
  • United Kingdom to Ontario
Search Deals
Alaska Airlines
  • Alaska Airlines
  • 12/11-31/12
  • 1 total stop
  • 16h 21m total
  • United Kingdom to Ontario
Search Deals
Highest demand for flights based on searches. 1% potential increase in price (£6 potential increase over avg. return price).
Search Deals
Cheapest flight prices on average. 1% potential price decrease (£5 potential savings vs. average return price).
Search Deals
Average for round-trip flights in September 2026
Search Deals

Cheapflights Fare Finder

 
Use the filters below to find and compare flights from the United Kingdom to Ontario that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest return flight

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 10/12

14:45-22:59

1 stop16h 14m

Ontario

Wed 31/12

00:00-09:00

Nonstop0h 00m

£356

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Mon 9/11

14:45-23:06

1 stop16h 21m

Ontario

Wed 31/12

00:00-09:00

Nonstop0h 00m

£388

BirminghamOntario

BHX Birmingham - ONT Ontario

BHXONT

Birmingham

Thu 5/11

16:55-19:28

3 stops34h 33m

Ontario

Wed 31/12

00:00-09:00

Nonstop0h 00m

£401

ManchesterOntario

MAN Manchester - ONT Ontario

MANONT

Manchester

Sun 13/12

09:40-21:53

2 stops20h 13m

Ontario

Wed 31/12

00:00-09:00

Nonstop0h 00m

£407

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Sat 21/11

13:45-20:15

1 stop14h 30m

Ontario

Tue 1/12

13:40-09:40

1 stop12h 00m

£409

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 1/10

14:50-20:58

1 stop14h 08m

Ontario

Wed 14/10

13:24-12:35

1 stop15h 11m

£410

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Thu 22/10

14:50-20:58

1 stop14h 08m

Ontario

Thu 29/10

13:32-09:40

1 stop13h 08m

£410

LondonOntario

LHR London Heathrow - ONT Ontario

LHRONT

London Heathrow

Sat 7/11

10:25-18:47

1 stop16h 22m

Ontario

Wed 11/11

13:29-09:40

1 stop12h 11m

£410

ManchesterOntario

MAN Manchester - ONT Ontario

MANONT

Manchester

Fri 4/12

05:50-18:38

2 stops20h 48m

Ontario

Wed 31/12

00:00-09:00

Nonstop0h 00m

£418

ManchesterOntario

MAN Manchester - ONT Ontario

MANONT

Manchester

Wed 11/11

12:40-20:54

1 stop16h 14m

Ontario

Wed 31/12

00:00-09:00

Nonstop0h 00m

£418

Flights are sorted by cheapest return flights first.

Deals found on 19/9

Showing 1-10 of 60 resultsSorted by cheapest first
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Best time to book a flight from United Kingdom to Ontario

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

Cheapflights Insights

Everything you need to know about your flight from the United Kingdom to Ontario

What is the cheapest month to book a flight from United Kingdom to Ontario?

Currently, January is the cheapest month in which you can book a flight from United Kingdom to Ontario (average of £416). Flying from United Kingdom to Ontario in June is currently the most expensive (average of £664). 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.

Reviews of airlines servicing Ontario

Read through reviews of airlines operating flights from the United Kingdom to Ontario, such as Alaska Airlines,Delta, andUnited Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
7.9
Good
12,960 reviews
Check prices

Boarding

8.1

Food

7.0

Comfort

7.8

Overall

7.9

Crew

8.5

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
12,960 reviews
Alaska Airlines
7.9
Good
12,960 reviews
Check prices

Boarding

8.1

Food

7.0

Comfort

7.8

Overall

7.9

Crew

8.5

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.
Delta
7.8
Good
8,594 reviews
Alaska Airlines
7.9
Good
12,960 reviews
Check prices

Boarding

8.1

Food

7.0

Comfort

7.8

Overall

7.9

Crew

8.5

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
7.4
Good
10,227 reviews
Alaska Airlines
7.9
Good
12,960 reviews
Check prices

Boarding

8.1

Food

7.0

Comfort

7.8

Overall

7.9

Crew

8.5

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
7.4
Good
694 reviews
Alaska Airlines
7.9
Good
12,960 reviews
Check prices

Boarding

8.1

Food

7.0

Comfort

7.8

Overall

7.9

Crew

8.5

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
8,226 reviews
Alaska Airlines
7.9
Good
12,960 reviews
Check prices

Boarding

8.1

Food

7.0

Comfort

7.8

Overall

7.9

Crew

8.5

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 United Kingdom?

    Located just 3.1 mi from the city center, Ontario (ONT) is the airport most travelers will use when flying to Ontario from United Kingdom.

  • How long is the flight from United Kingdom to Ontario?

    For as low as £409, United Airlines can have you in Ontario from United Kingdom in 14h 30m. The distance from United Kingdom to Ontario is about 5407 mi. When browsing for deals, the options you’ll see will be for both direct flights and flights with stops.

  • What are the most popular routes from United Kingdom to Ontario?

    While some choose either London Gatwick - Ontario or Manchester - Ontario, London Heathrow - Ontario is the most popular route from United Kingdom to Ontario.

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

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

  • How can I find direct flights from United Kingdom to Ontario?

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

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

    Yes. Cheapflights offers flight deals from United Kingdom 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 United Kingdom to Ontario?

    Currently, January is the cheapest month in which you can book a flight from United Kingdom to Ontario (average of £416). Flying from United Kingdom to Ontario in June is currently the most expensive (average of £664). 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 3 airlines flying from United Kingdom to Ontario

AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest£376Average£545FlexibilityNo cancel feeOn-time69%
Search United Airlines flights
Virgin AtlanticCheapest£378Average£516FlexibilityNo cancel feeOn-time72%
Search Virgin Atlantic flights
British AirwaysCheapest£392Average£601FlexibilityNo cancel feeOn-time70%
Search British Airways flights

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How does Cheapflights help users find flights from United Kingdom to Ontario?

Deals for United Kingdom to Ontario flights are sourced from 900+ travel sites when you use Cheapflights. When all flight results come back, Cheapflights lets you sort and filter flights using different criteria to choose better, like price, airport, cabin class, and plenty of other options.

Why should you use Cheapflights to find cheap flight tickets from United Kingdom to Ontario?

Cheapflights simply makes it quick and affordable to book flights from United Kingdom to Ontario by bringing together all flight options from hundreds of airlines and agencies online — and put it in one place for you to choose from. Plus, Cheapflights is 100% free to use for all.

Can Cheapflights find flights from United Kingdom to Ontario with no change fees?

Need flexible booking options for your flight to Ontario from United Kingdom? Don’t worry, Cheapflights have you covered. Use our search filter to only show flights with no change fees.

Can Cheapflights notify me if prices for flights from United Kingdom to Ontario become cheaper?

Yes, Cheapflights has a feature called Price Alert, which notifies users when flight prices change. Track prices for your flight to Ontario from United Kingdom today and book when prices fit your budget.

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