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$290+ Cheap flights from Ontario (ONT) to the United Kingdom

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 9/24. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LHR
jun. 17 — jun. 241
mar. 6/17
mar. 6/24
1 adult, Economy
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Cheap flight deals from Ontario to United Kingdom

Keep the following information in mind while searching for Ontario to United Kingdom flight deals. Data was last updated junio 12, 2025.

Round-trip from

$609
(Delta)

One-way from

$322
(Trip.com)

Popular in

December

Cheapest in

October

Average price

$836
From Ontario to United Kingdom
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One-way flight from Ontario to United Kingdom
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Highest demand for flights based on searches. 9% potential increase in price ($75 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($22 potential savings vs. average RT price).
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Average for round-trip flights in June 2025
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Find flight deals from Ontario to United Kingdom

Cheapest flights from Ontario to United Kingdom
Explore the most affordable flight options available from Ontario to United Kingdom. Find the lowest fares from popular airlines and budget airlines, with prices last updated on junio 12, 2025.

This Delta deal was found by Cheapflights users on 6/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 7/151:15 pmONT - LHR
1 stop12h 35mDelta
mié. 7/305:25 pmLHR - ONT
1 stop25h 00mDelta
Deal found 6/12$609
This Iberia deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 10/52:30 pmONT - LHR
1 stop15h 55mIberia
mar. 10/146:10 amLHR - ONT
2 stops25h 52mIberia
Deal found 6/11$657
This Air Canada deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 9/16:38 pmONT - EDI
2 stops28h 42mAir Canada
vie. 9/129:00 amEDI - ONT
2 stops43h 43mAir Canada
Deal found 6/11$658
This Priceline deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 8/122:57 pmONT - LHR
1 stop15h 28mBritish Airways
mar. 9/211:30 amLHR - ONT
2 stops19h 18mBritish Airways
Deal found 6/10$659
This Expedia deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 8/125:05 amONT - LHR
2 stops17h 25mAir Canada
mar. 9/25:40 pmLHR - ONT
2 stops26h 52mAir Canada
Deal found 6/10$664
This United Airlines deal was found by Cheapflights users on 6/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
vie. 8/86:39 pmONT - LHR
2 stops51h 51mUnited Airlines
vie. 8/2212:05 pmLHR - ONT
2 stops32h 08mUnited Airlines
Deal found 6/12$669
This United Airlines deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 9/26:50 pmONT - MAN
2 stops31h 30mUnited Airlines
mar. 9/309:10 amMAN - ONT
2 stops20h 14mUnited Airlines
Deal found 6/11$671
This American Airlines deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 8/34:45 pmONT - LHR
1 stop12h 05mAmerican Airlines
mar. 8/1911:15 amLHR - ONT
1 stop14h 37mAmerican Airlines
Deal found 6/11$672
This KLM deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 7/2711:40 amONT - EDI
1 stop16h 25mKLM
mar. 8/59:00 amEDI - ONT
1 stop21h 27mKLM
Deal found 6/10$673
This United Airlines deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 7/276:00 amONT - EDI
2 stops18h 05mUnited Airlines
mar. 8/511:30 amEDI - ONT
2 stops19h 22mUnited Airlines
Deal found 6/11$678
This Virgin Atlantic deal was found by Cheapflights users on 6/12. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Virgin Atlantic is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 8/42:14 pmONT - LHR
2 stops18h 01mVirgin Atlantic
mar. 8/1211:20 amLHR - ONT
2 stops20h 20mVirgin Atlantic
Deal found 6/12$694
This KLM deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 11/1612:00 pmONT - LHR
1 stop14h 35mKLM
vie. 11/282:20 pmLHR - ONT
1 stop16h 21mKLM
Deal found 6/11$696

Cheapflights Fare Finder

Customize your flight search to find flights from Ontario to United Kingdom that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated junio 12, 2025.
Use the filters below to find and compare flights from Ontario to the United Kingdom that are best for you.

Fly from

Ontario

Fly to

United Kingdom

Route

Depart

Return

Price

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mar. 7/15

1:15 pm-9:50 am

1 stop12h 35m

London Heathrow

mié. 7/30

5:25 pm-10:25 am

1 stop25h 00m

$609

OntarioLondon

ONT - LHR

ONTLHR

Ontario

dom. 10/5

2:30 pm-2:25 pm

1 stop15h 55m

London Heathrow

mar. 10/14

6:10 am-12:02 am

2 stops25h 52m

$657

OntarioEdinburgh

ONT - EDI

ONTEDI

Ontario

lun. 9/1

6:38 pm-7:20 am

2 stops28h 42m

Edinburgh Turnhouse

vie. 9/12

9:00 am-8:43 pm

2 stops43h 43m

$658

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mar. 8/12

2:57 pm-2:25 pm

1 stop15h 28m

London Heathrow

mar. 9/2

11:30 am-10:48 pm

2 stops19h 18m

$659

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mar. 8/12

5:05 am-6:30 am

2 stops17h 25m

London Heathrow

mar. 9/2

5:40 pm-12:32 pm

2 stops26h 52m

$664

OntarioLondon

ONT - LHR

ONTLHR

Ontario

vie. 8/8

6:39 pm-6:30 am

2 stops51h 51m

London Heathrow

vie. 8/22

12:05 pm-12:13 pm

2 stops32h 08m

$669

OntarioManchester

ONT - MAN

ONTMAN

Ontario

mar. 9/2

6:50 pm-10:20 am

2 stops31h 30m

Manchester

mar. 9/30

9:10 am-9:24 pm

2 stops20h 14m

$671

OntarioLondon

ONT - LHR

ONTLHR

Ontario

dom. 8/3

4:45 pm-12:50 pm

1 stop12h 05m

London Heathrow

mar. 8/19

11:15 am-5:52 pm

1 stop14h 37m

$672

OntarioEdinburgh

ONT - EDI

ONTEDI

Ontario

dom. 7/27

11:40 am-12:05 pm

1 stop16h 25m

Edinburgh Turnhouse

mar. 8/5

9:00 am-10:27 pm

1 stop21h 27m

$673

OntarioEdinburgh

ONT - EDI

ONTEDI

Ontario

dom. 7/27

6:00 am-8:05 am

2 stops18h 05m

Edinburgh Turnhouse

mar. 8/5

11:30 am-10:11 pm

1 stop18h 41m

$678

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/11

Showing 1-10 of 60 results
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Best time to book a flight from Ontario to United Kingdom

Have a flexible travel schedule? Discover the best time to fly to United Kingdom from Ontario with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

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

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

Currently, November is the cheapest month in which you can book a flight from Ontario to United Kingdom (average of $661). Flying from Ontario to United Kingdom in June is currently the most expensive (average of $1,108). 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.

What is the cheapest time of day to fly from ONT to GB?

Find hourly flight availability from Ontario to United Kingdom. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated junio 12, 2025.

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Ontario to United Kingdom as you normally would.

Rainfall in United Kingdom by month

Plan your trip to United Kingdom by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in United Kingdom ranges from 1.6 - 2.8 inches per month. January is typically the wettest month, when rainfall can reach 2.8 in. July is typically the driest time to visit United Kingdom when rainfall is around 1.6 in.

Temperature in United Kingdom by month

Plan your trip to United Kingdom by taking into account the average temperature totals by month.

If weather is an important factor for your trip to United Kingdom, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 62.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 39.2 F).

Reviews of airlines servicing United Kingdom

Get insights into the airlines that provide service to United Kingdom. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to United Kingdom. Reviews last updated junio 12, 2025.
Get a feel of what it's like to fly with Delta, KLM and United Airlines from Ontario to United Kingdom by reading reviews from past customers. In addition to providing an overall rating, users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,950 reviews

Entertainment

7.9

Crew

8.5

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Delta
8.0
Very good
7,950 reviews
Delta
8.0
Very good
7,950 reviews

Entertainment

7.9

Crew

8.5

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
KLM
7.8
Good
1,358 reviews
Delta
8.0
Very good
7,950 reviews

Entertainment

7.9

Crew

8.5

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
United Airlines
7.4
Good
8,790 reviews
Delta
8.0
Very good
7,950 reviews

Entertainment

7.9

Crew

8.5

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
Virgin Atlantic
7.4
Good
652 reviews
Delta
8.0
Very good
7,950 reviews

Entertainment

7.9

Crew

8.5

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.
JetBlue
7.3
Good
2,925 reviews
Delta
8.0
Very good
7,950 reviews

Entertainment

7.9

Crew

8.5

Overall

8.0

Comfort

7.9

Boarding

8.2

Food

7.3

Reviews

1 / 20
10.0
Excellent

Aaron,Oct 2024

LAX - LHR

This was a flight operated by Virgin Atlantic in their Upper Class cabin. Overall, an outstanding experience.

Related info for your journey

Find useful and relevant information for your journey from Ontario to United Kingdom. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from Ontario to United Kingdom?

    If you book a flight to United Kingdom from Ontario, you will be flying from Ontario, which is the city’s only airport. Ontario (ONT) is located 3.1 mi from the center of Ontario.

  • What are the cheapest airlines to fly from Ontario to United Kingdom one-way?

    The cheapest airline one-way is JetBlue, with whom users have recently found tickets for as low as $394. However, be on the lookout for offers from Delta and KLM, as they are both options that can get you from Ontario to United Kingdom for a low price.

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

    Most travelers choose Ontario - London Heathrow, Ontario - Edinburgh Turnhouse or Ontario - Manchester when deciding on the best route from Ontario to United Kingdom.

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

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

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

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

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

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

    Currently, November is the cheapest month in which you can book a flight from Ontario to United Kingdom (average of $661). Flying from Ontario to United Kingdom in June is currently the most expensive (average of $1,108). 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

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Alternative routes for Ontario to United Kingdom

See prices for flight routes from nearby airports that may be better suited for you.
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Top 7 airlines flying from Ontario to United Kingdom

Discover the top 7 airlines that operate flights from Ontario to United Kingdom. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated junio 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
Virgin AtlanticCheapest$454Average$765FlexibilityNo cancel feeOn-time72%
IberiaCheapest$582Average$670FlexibilityNo cancel feeOn-time77%
DeltaCheapest$594Average$1,081FlexibilityNo cancel feeOn-timeN/A
KLMCheapest$608Average$763FlexibilityNo cancel feeOn-time75%
British AirwaysCheapest$611Average$917FlexibilityNo cancel feeOn-time70%
United AirlinesCheapest$633Average$796FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$636Average$879FlexibilityNo cancel feeOn-time71%

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