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$210+ 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 3/25. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LHR
Jan 11 — Jan 181
Sun 1/11
Sun 1/18
1 adult, Economy
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Cheap 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 December 12, 2025.

This American Airlines deal was found by Cheapflights users on 12/11. 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.
Wed 12/3112:45 pmONT - MAN
2 stops19h 35mAmerican Airlines
Thu 1/155:40 amMAN - ONT
2 stops21h 05mAmerican Airlines
Deal found 12/11$621
This Delta deal was found by Cheapflights users on 12/11. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/316:00 amONT - MAN
2 stops26h 35mDelta
Thu 1/151:30 pmMAN - ONT
1 stop30h 01mDelta
Deal found 12/11$628
This Cheapflightsfares deal was found by Cheapflights users on 12/11. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/304:47 pmONT - LHR
1 stop12h 28mBritish Airways
Tue 1/133:00 pmLHR - ONT
1 stop15h 48mBritish Airways
Deal found 12/11$696
This oojo deal was found by Cheapflights users on 12/11. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/154:47 pmONT - MAN
2 stops15h 43mBritish Airways
Fri 1/1611:50 amMAN - ONT
2 stops18h 23mBritish Airways
Deal found 12/11$759
This United Airlines deal was found by Cheapflights users on 12/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/266:00 amONT - LHR
1 stop22h 00mUnited Airlines
Fri 1/93:10 pmLHR - ONT
2 stops29h 07mUnited Airlines
Deal found 12/10$796
This United Airlines deal was found by Cheapflights users on 12/11. 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.
Mon 12/156:41 pmONT - EDI
3 stops29h 14mUnited Airlines
Mon 12/2212:30 pmEDI - ONT
2 stops41h 22mUnited Airlines
Deal found 12/11$833
This oojo deal was found by Cheapflights users on 12/11. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/144:47 pmONT - MAN
2 stops17h 18mBritish Airways
Thu 1/1511:40 amMAN - ONT
2 stops19h 08mBritish Airways
Deal found 12/11$838
This United Airlines deal was found by Cheapflights users on 12/11. 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.
Thu 12/255:05 amONT - LHR
1 stop20h 35mUnited Airlines
Sun 1/1110:00 amLHR - ONT
1 stop19h 58mUnited Airlines
Deal found 12/11$842
This United Airlines deal was found by Cheapflights users on 12/11. 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.
Fri 12/266:00 amONT - LHR
1 stop22h 00mUnited Airlines
Sat 1/103:10 pmLHR - ONT
3 stops28h 08mUnited Airlines
Deal found 12/11$846
This KLM deal was found by Cheapflights users on 12/11. 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.
Wed 12/3111:15 amONT - LHR
1 stop13h 45mKLM
Tue 1/1310:45 amLHR - ONT
1 stop13h 27mKLM
Deal found 12/11$887
This oojo deal was found by Cheapflights users on 12/11. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/154:47 pmONT - MAN
2 stops15h 43mBritish Airways
Sat 1/176:15 amMAN - ONT
2 stops20h 30mBritish Airways
Deal found 12/11$897
This oojo deal was found by Cheapflights users on 12/11. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/112:56 pmONT - MAN
2 stops17h 34mBritish Airways
Sun 1/186:45 amMAN - ONT
2 stops20h 00mBritish Airways
Deal found 12/11$928

Find 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 December 12, 2025.

Most accurate provider

Gotogate
3 stars

Most trusted provider

Gotogate
3 stars

Round-trip from

$605
(Flighttix)

One-way from

$210
(oojo)

Popular in

December

Cheapest in

September

Average price

$1,027
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 ($100 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($30 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 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 December 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

OntarioEdinburgh

ONT - EDI

ONTEDI

Ontario

Thu 2/5

4:45 pm-5:40 pm

2 stops16h 55m

Edinburgh Turnhouse

Fri 2/13

10:55 am-10:04 pm

2 stops19h 09m

$609

OntarioEdinburgh

ONT - EDI

ONTEDI

Ontario

Mon 2/9

4:45 pm-6:10 pm

2 stops17h 25m

Edinburgh Turnhouse

Thu 2/19

6:50 am-10:04 pm

2 stops23h 14m

$609

OntarioNewcastle upon Tyne

ONT - NCL

ONTNCL

Ontario

Sun 1/25

4:45 pm-7:25 pm

2 stops18h 40m

Newcastle upon Tyne

Sun 2/1

6:40 am-10:13 pm

2 stops23h 33m

$610

OntarioManchester

ONT - MAN

ONTMAN

Ontario

Sun 2/22

5:06 pm-6:05 pm

2 stops16h 59m

Manchester

Fri 3/6

11:50 am-11:58 pm

2 stops20h 08m

$615

OntarioManchester

ONT - MAN

ONTMAN

Ontario

Wed 12/31

12:45 pm-4:20 pm

2 stops19h 35m

Manchester

Thu 1/15

5:40 am-6:45 pm

2 stops21h 05m

$621

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 2/13

7:10 am-11:40 am

1 stop20h 30m

London Heathrow

Sat 2/21

6:05 am-10:49 pm

2 stops24h 44m

$626

OntarioManchester

ONT - MAN

ONTMAN

Ontario

Wed 12/31

6:00 am-4:35 pm

2 stops26h 35m

Manchester

Thu 1/15

1:30 pm-11:31 am

1 stop30h 01m

$628

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Fri 1/23

1:10 pm-10:00 am

1 stop12h 50m

London Heathrow

Sat 1/31

6:30 am-10:51 pm

2 stops24h 21m

$629

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Sat 1/24

1:10 pm-10:00 am

1 stop12h 50m

London Heathrow

Sat 1/31

6:30 am-10:51 pm

2 stops24h 21m

$629

OntarioLondon

ONT - LHR

ONTLHR

Ontario

Thu 3/5

7:30 am-11:55 am

1 stop20h 25m

London Heathrow

Thu 3/12

6:30 am-9:04 pm

2 stops21h 34m

$629

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/10

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 $226). Flying from Ontario to United Kingdom in June is currently the most expensive (average of $556). 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 December 12, 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 December 12, 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
8,008 reviews

Food

7.3

Comfort

7.9

Crew

8.5

Entertainment

7.9

Overall

7.9

Boarding

8.1

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
8,008 reviews
Delta
7.9
Good
8,008 reviews

Food

7.3

Comfort

7.9

Crew

8.5

Entertainment

7.9

Overall

7.9

Boarding

8.1

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
9,095 reviews
Delta
7.9
Good
8,008 reviews

Food

7.3

Comfort

7.9

Crew

8.5

Entertainment

7.9

Overall

7.9

Boarding

8.1

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
11,048 reviews
Delta
7.9
Good
8,008 reviews

Food

7.3

Comfort

7.9

Crew

8.5

Entertainment

7.9

Overall

7.9

Boarding

8.1

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
3,045 reviews
Delta
7.9
Good
8,008 reviews

Food

7.3

Comfort

7.9

Crew

8.5

Entertainment

7.9

Overall

7.9

Boarding

8.1

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
7,571 reviews
Delta
7.9
Good
8,008 reviews

Food

7.3

Comfort

7.9

Crew

8.5

Entertainment

7.9

Overall

7.9

Boarding

8.1

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 British Airways, American Airlines, and Iberia fly from Ontario to United Kingdom in about 16h 55m. The time it takes to get you to your destination can typically vary by up to 3h 35m. 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 most popular routes from Ontario to United Kingdom?

    Most travelers choose Ontario - London Heathrow, Ontario - Manchester 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, October is the cheapest month in which you can book a flight from Ontario to United Kingdom (average of $226). Flying from Ontario to United Kingdom in June is currently the most expensive (average of $556). 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 December 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
Virgin AtlanticCheapest$469Average$765FlexibilityNo cancel feeOn-time72%
DeltaCheapest$543Average$930FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$567Average$729FlexibilityNo cancel feeOn-time71%
KLMCheapest$580Average$672FlexibilityNo cancel feeOn-time75%
IberiaCheapest$615Average$728FlexibilityNo cancel feeOn-time77%
British AirwaysCheapest$653Average$881FlexibilityNo cancel feeOn-time70%
United AirlinesCheapest$665Average$837FlexibilityNo cancel feeOn-time69%

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