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$324+ 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 9/13. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LHR
ago. 4 — ago. 111
lun. 8/4
lun. 8/11
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 julio 30, 2025.

Round-trip from

$494
(Delta)

One-way from

$325
(Kiwi.com)

Popular in

December

Cheapest in

October

Average price

$779
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. 10% potential increase in price ($86 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($24 potential savings vs. average RT price).
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Average for round-trip flights in July 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 julio 30, 2025.

This Delta deal was found by Cheapflights users on 7/28. 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.
mié. 10/111:50 amONT - LHR
1 stop15h 30mDelta
jue. 10/306:20 amLHR - ONT
2 stops22h 00mDelta
Deal found 7/28$524
This Delta deal was found by Cheapflights users on 7/30. 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.
lun. 8/1111:45 amONT - EDI
1 stop16h 20mDelta
mar. 8/269:00 amEDI - ONT
1 stop18h 11mDelta
Deal found 7/30$532
This Virgin Atlantic deal was found by Cheapflights users on 7/27. 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. 9/156:00 amONT - LHR
1 stop24h 15mVirgin Atlantic
mar. 9/3011:15 amLHR - ONT
2 stops20h 27mVirgin Atlantic
Deal found 7/27$575
This KLM deal was found by Cheapflights users on 7/28. 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.
mié. 8/1311:45 amONT - LHR
1 stop17h 45mKLM
sáb. 8/309:20 amLHR - ONT
1 stop17h 51mKLM
Deal found 7/28$582
This lol.travel deal was found by Cheapflights users on 7/29. 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 lol.travel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dom. 8/171:34 pmONT - LHR
1 stop14h 46mUnited Airlines
mar. 9/22:50 pmLHR - ONT
1 stop13h 53mUnited Airlines
Deal found 7/29$622
This lol.travel deal was found by Cheapflights users on 7/30. 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 lol.travel is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 9/87:00 amONT - BHX
2 stops17h 40mUnited Airlines
mar. 9/239:20 amBHX - ONT
2 stops34h 53mUnited Airlines
Deal found 7/30$627
This oojo deal was found by Cheapflights users on 7/30. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 12/38:48 amONT - MAN
2 stops18h 07mBritish Airways
mié. 12/107:30 pmMAN - ONT
2 stops34h 07mBritish Airways
Deal found 7/30$632
This Cheapflightsfares deal was found by Cheapflights users on 7/29. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 10/2812:47 pmONT - LHR
1 stop12h 48mBritish Airways
mar. 11/42:55 pmLHR - ONT
1 stop15h 34mBritish Airways
Deal found 7/29$632
This Finnair deal was found by Cheapflights users on 7/30. 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 Finnair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mar. 8/1911:59 pmONT - LGW
2 stops24h 11mMultiple Airlines
vie. 10/33:05 pmLGW - ONT
2 stops28h 51mMultiple Airlines
Deal found 7/30$632
This Air Canada deal was found by Cheapflights users on 7/29. 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.
dom. 8/176:31 pmONT - EDI
2 stops30h 34mAir Canada
mar. 8/2611:15 amEDI - ONT
2 stops38h 14mAir Canada
Deal found 7/29$643
This United Airlines deal was found by Cheapflights users on 7/29. 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. 8/197:00 amONT - EDI
2 stops17h 05mUnited Airlines
mié. 8/279:00 amEDI - ONT
2 stops40h 29mUnited Airlines
Deal found 7/29$650
This Iberia deal was found by Cheapflights users on 7/28. 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.
mar. 8/192:57 pmONT - LHR
1 stop15h 28mIberia
jue. 9/412:00 pmLHR - ONT
1 stop14h 54mIberia
Deal found 7/28$655

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 julio 30, 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

mié. 10/1

11:50 am-11:20 am

1 stop15h 30m

London Heathrow

jue. 10/30

6:20 am-9:20 pm

2 stops22h 00m

$524

OntarioEdinburgh

ONT - EDI

ONTEDI

Ontario

lun. 8/11

11:45 am-12:05 pm

1 stop16h 20m

Edinburgh Turnhouse

mar. 8/26

9:00 am-7:11 pm

1 stop18h 11m

$532

OntarioLondon

ONT - LHR

ONTLHR

Ontario

lun. 9/15

9:50 am-9:50 am

1 stop16h 00m

London Heathrow

vie. 9/26

9:20 am-7:15 pm

1 stop17h 55m

$569

OntarioLondon

ONT - LHR

ONTLHR

Ontario

lun. 9/15

6:00 am-2:15 pm

1 stop24h 15m

London Heathrow

mar. 9/30

11:15 am-11:42 pm

2 stops20h 27m

$575

OntarioLondon

ONT - LHR

ONTLHR

Ontario

dom. 8/17

1:34 pm-12:20 pm

1 stop14h 46m

London Heathrow

mar. 9/2

2:50 pm-8:43 pm

1 stop13h 53m

$622

OntarioBirmingham

ONT - BHX

ONTBHX

Ontario

lun. 9/8

7:00 am-8:40 am

2 stops17h 40m

Birmingham

mar. 9/23

9:20 am-12:13 pm

2 stops34h 53m

$627

OntarioManchester

ONT - MAN

ONTMAN

Ontario

mié. 12/3

8:48 am-10:55 am

2 stops18h 07m

Manchester

mié. 12/10

7:30 pm-9:37 pm

2 stops34h 07m

$632

OntarioLondon

ONT - LGW

ONTLGW

Ontario

mar. 8/19

11:59 pm-8:10 am

2 stops24h 11m

London Gatwick

vie. 10/3

3:05 pm-11:56 am

2 stops28h 51m

$632

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mar. 10/28

12:47 pm-8:35 am

1 stop12h 48m

London Heathrow

mar. 11/4

2:55 pm-10:29 pm

1 stop15h 34m

$632

OntarioEdinburgh

ONT - EDI

ONTEDI

Ontario

dom. 8/17

6:31 pm-9:05 am

2 stops30h 34m

Edinburgh Turnhouse

mar. 8/26

11:15 am-5:29 pm

2 stops38h 14m

$643

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/30

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 $1,097). 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 julio 30, 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.

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 julio 30, 2025.
Read through reviews of airlines operating flights from Ontario to the United Kingdom, such as Delta, KLM, and United Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
7,980 reviews

Food

7.3

Comfort

7.9

Boarding

8.2

Overall

8.0

Entertainment

7.9

Crew

8.5

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
7,980 reviews
Delta
8.0
Very good
7,980 reviews

Food

7.3

Comfort

7.9

Boarding

8.2

Overall

8.0

Entertainment

7.9

Crew

8.5

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
1,383 reviews
Delta
8.0
Very good
7,980 reviews

Food

7.3

Comfort

7.9

Boarding

8.2

Overall

8.0

Entertainment

7.9

Crew

8.5

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
8,896 reviews
Delta
8.0
Very good
7,980 reviews

Food

7.3

Comfort

7.9

Boarding

8.2

Overall

8.0

Entertainment

7.9

Crew

8.5

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
655 reviews
Delta
8.0
Very good
7,980 reviews

Food

7.3

Comfort

7.9

Boarding

8.2

Overall

8.0

Entertainment

7.9

Crew

8.5

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.
American Airlines
7.2
Good
10,000 reviews
Delta
8.0
Very good
7,980 reviews

Food

7.3

Comfort

7.9

Boarding

8.2

Overall

8.0

Entertainment

7.9

Crew

8.5

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 British Airways, with whom users have recently found tickets for as low as $382. However, be on the lookout for offers from Iberia and United Airlines, 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 - London Gatwick 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 $1,097). 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 julio 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$572Average$770FlexibilityNo cancel feeOn-timeN/A
KLMCheapest$580Average$704FlexibilityNo cancel feeOn-time75%
IberiaCheapest$582Average$670FlexibilityNo cancel feeOn-time77%
Virgin AtlanticCheapest$629Average$889FlexibilityNo cancel feeOn-time72%
United AirlinesCheapest$633Average$777FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$648Average$957FlexibilityNo cancel feeOn-time71%
British AirwaysCheapest$648Average$881FlexibilityNo cancel feeOn-time70%

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