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$335+ 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 11/28. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LHR
Nov 29 — Dec 61
Sat 11/29
Sat 12/6
1 adult, Economy
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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 October 30, 2025.

This Netflights deal was found by Cheapflights users on 10/28. 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 Netflights is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/26:40 amONT - LHR
1 stop19h 50mVirgin Atlantic
Tue 12/1610:45 amLHR - ONT
1 stop21h 13mVirgin Atlantic
Deal found 10/28$591
This Trip.com deal was found by Cheapflights users on 10/30. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/912:16 pmONT - LHR
1 stop15h 24mVirgin Atlantic
Tue 11/252:45 pmLHR - ONT
1 stop16h 10mVirgin Atlantic
Deal found 10/30$610
This Delta deal was found by Cheapflights users on 10/29. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/26:40 amONT - LHR
1 stop19h 50mDelta
Tue 12/96:30 amLHR - ONT
2 stops21h 09mDelta
Deal found 10/29$611
This oojo deal was found by Cheapflights users on 10/28. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/257:00 amONT - LHR
1 stop15h 50mBritish Airways
Wed 1/143:00 pmLHR - ONT
1 stop15h 49mBritish Airways
Deal found 10/28$616
This Delta deal was found by Cheapflights users on 10/29. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/276:00 amONT - MAN
2 stops20h 30mDelta
Wed 12/31:30 pmMAN - ONT
2 stops29h 43mDelta
Deal found 10/29$618
This oojo deal was found by Cheapflights users on 10/29. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/1812:46 pmONT - LHR
1 stop13h 14mBritish Airways
Fri 12/58:20 amLHR - ONT
1 stop17h 57mBritish Airways
Deal found 10/29$618
This Delta deal was found by Cheapflights users on 10/29. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/2610:25 pmONT - MAN
1 stop28h 05mDelta
Wed 12/31:30 pmMAN - ONT
1 stop17h 34mDelta
Deal found 10/29$619
This Finnair deal was found by Cheapflights users on 10/29. 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 Finnair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/210:47 amONT - LHR
1 stop13h 48mMultiple Airlines
Tue 12/1611:45 amLHR - ONT
1 stop15h 54mMultiple Airlines
Deal found 10/29$619
This Finnair deal was found by Cheapflights users on 10/28. 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 Finnair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/92:53 pmONT - LHR
1 stop12h 47mMultiple Airlines
Tue 11/2510:05 amLHR - ONT
1 stop16h 17mMultiple Airlines
Deal found 10/28$620
This Justfly.com deal was found by Cheapflights users on 10/28. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/257:05 amONT - LHR
1 stop15h 20mVirgin Atlantic
Wed 1/145:05 pmLHR - ONT
2 stops37h 33mVirgin Atlantic
Deal found 10/28$621
This KLM deal was found by Cheapflights users on 10/28. 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.
Tue 11/187:05 amONT - LHR
1 stop16h 45mKLM
Thu 11/276:30 amLHR - ONT
2 stops21h 12mKLM
Deal found 10/28$622
This Justfly.com deal was found by Cheapflights users on 10/30. 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 Justfly.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/511:48 amONT - LHR
1 stop14h 42mVirgin Atlantic
Wed 11/126:30 amLHR - ONT
2 stops24h 25mVirgin Atlantic
Deal found 10/30$625

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 October 30, 2025.

Most accurate provider

Gotogate
3 stars

Most trusted provider

Gotogate
3 stars

Round-trip from

$591
(Netflights)

One-way from

$335
(Kiwi.com)

Popular in

December

Cheapest in

September

Average price

$618
Provider with most accurate pricing for Los Angeles-London (LON) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Los Angeles-London (LON) flights.
Search Deals
From Ontario to United Kingdom
Search Deals
One-way flight from Ontario to United Kingdom
Search Deals
Highest demand for flights based on searches. 12% potential increase in price ($102 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($26 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 2025
Search Deals

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 October 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

OntarioManchester

ONT - MAN

ONTMAN

Ontario

Wed 11/26

6:00 am-10:10 am

2 stops20h 10m

Manchester

Wed 12/3

1:30 pm-11:04 pm

1 stop17h 34m

$618

OntarioManchester

ONT - MAN

ONTMAN

Ontario

Thu 11/27

6:00 am-10:30 am

2 stops20h 30m

Manchester

Wed 12/3

1:30 pm-11:13 am

2 stops29h 43m

$618

OntarioEdinburgh

ONT - EDI

ONTEDI

Ontario

Sun 2/1

6:00 am-7:55 am

2 stops17h 55m

Edinburgh Turnhouse

Thu 2/12

9:25 am-9:59 pm

2 stops20h 34m

$619

OntarioEdinburgh

ONT - EDI

ONTEDI

Ontario

Mon 1/5

7:10 am-12:10 pm

2 stops21h 00m

Edinburgh Turnhouse

Mon 1/12

6:35 pm-10:48 pm

2 stops36h 13m

$624

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 1/9

6:00 am-9:00 am

2 stops19h 00m

London Heathrow

Sun 1/18

6:30 am-10:29 pm

2 stops23h 59m

$633

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Tue 12/2

6:00 am-7:05 am

2 stops17h 05m

London Heathrow

Tue 12/16

1:00 pm-11:58 pm

2 stops18h 58m

$633

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Thu 11/27

7:05 am-7:50 am

1 stop16h 45m

London Heathrow

Thu 12/4

12:30 pm-11:04 pm

1 stop18h 34m

$649

OntarioManchester

ONT - MAN

ONTMAN

Ontario

Tue 11/18

7:00 am-10:20 am

2 stops19h 20m

Manchester

Tue 12/16

6:00 am-10:49 pm

2 stops24h 49m

$649

OntarioManchester

ONT - MAN

ONTMAN

Ontario

Wed 11/26

7:00 am-10:20 am

2 stops19h 20m

Manchester

Wed 12/3

6:00 am-10:49 pm

2 stops24h 49m

$649

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Wed 2/18

1:45 pm-12:00 pm

1 stop14h 15m

London Heathrow

Tue 2/24

10:05 am-5:41 pm

1 stop15h 36m

$657

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/29

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, October is the cheapest month in which you can book a flight from Ontario to United Kingdom (average of $251). Flying from Ontario to United Kingdom in June is currently the most expensive (average of $564). 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 October 30, 2025.

When flying from Ontario to United Kingdom, the time of day you fly usually plays a role in the price. Save by searching for a flight in the morning, which can drop the price by up to 27% versus a flight at noon.

What is the cheapest day to fly from Ontario to United Kingdom?

Use this chart to determine the cheapest time to fly round-trip from Ontario to United Kingdom. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Ontario to United Kingdom flight should consider departing on Monday mornings when fares are most often at their lowest. Sunday evenings flights should be avoided if possible as fares are typically the most expensive at this time.

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 October 30, 2025.
Read through reviews of airlines operating flights from Ontario to the United Kingdom, such as Delta, United Airlines, and American Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
7.9
Good
7,998 reviews

Comfort

7.9

Entertainment

7.9

Food

7.3

Overall

7.9

Boarding

8.2

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
7.9
Good
7,998 reviews
Delta
7.9
Good
7,998 reviews

Comfort

7.9

Entertainment

7.9

Food

7.3

Overall

7.9

Boarding

8.2

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
8,996 reviews
Delta
7.9
Good
7,998 reviews

Comfort

7.9

Entertainment

7.9

Food

7.3

Overall

7.9

Boarding

8.2

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
11,034 reviews
Delta
7.9
Good
7,998 reviews

Comfort

7.9

Entertainment

7.9

Food

7.3

Overall

7.9

Boarding

8.2

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.
Iberia
7.0
Good
3,004 reviews
Delta
7.9
Good
7,998 reviews

Comfort

7.9

Entertainment

7.9

Food

7.3

Overall

7.9

Boarding

8.2

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.
British Airways
6.7
Okay
7,488 reviews
Delta
7.9
Good
7,998 reviews

Comfort

7.9

Entertainment

7.9

Food

7.3

Overall

7.9

Boarding

8.2

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.

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

    Airlines like Delta, United Airlines, and British Airways fly from Ontario to United Kingdom in about 17h 55m. The time it takes to get you to your destination can typically vary by up to 3h 05m. Airlines will cover a distance of 5118 mi. Both multi-stop and nonstop flights can be found to your destination and back.

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

    The cheapest airline one-way is United Airlines, with whom users have recently found tickets for as low as $399. However, be on the lookout for offers from British Airways and Delta, 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 - London Gatwick 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, October is the cheapest month in which you can book a flight from Ontario to United Kingdom (average of $251). Flying from Ontario to United Kingdom in June is currently the most expensive (average of $564). 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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Top 6 airlines flying from Ontario to United Kingdom

Discover the top 6 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 October 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$543Average$932FlexibilityNo cancel feeOn-timeN/A
KLMCheapest$580Average$672FlexibilityNo cancel feeOn-time75%
IberiaCheapest$615Average$670FlexibilityNo cancel feeOn-time77%
American AirlinesCheapest$626Average$1,041FlexibilityNo cancel feeOn-time71%
British AirwaysCheapest$660Average$885FlexibilityNo cancel feeOn-time70%
United AirlinesCheapest$675Average$844FlexibilityNo cancel feeOn-time69%

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