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$218+ 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 4/14. Fares are subject to change and may not be available on all flights or dates of travel.
ONT — LHR
ene. 3 — ene. 101
sáb. 1/3
sáb. 1/10
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 diciembre 4, 2025.

This British Airways deal was found by Cheapflights users on 12/3. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mié. 12/3112:45 pmONT - MAN
2 stops19h 35mBritish Airways
jue. 1/157:45 amMAN - ONT
2 stops22h 28mBritish Airways
Deal found 12/3$571
This Delta deal was found by Cheapflights users on 12/3. 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. 12/101:29 pmONT - LHR
1 stop12h 31mDelta
mar. 12/2310:45 amLHR - ONT
1 stop21h 09mDelta
Deal found 12/3$598
This Delta deal was found by Cheapflights users on 12/2. 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. 12/316:00 amONT - MAN
2 stops26h 35mDelta
jue. 1/151:30 pmMAN - ONT
1 stop30h 01mDelta
Deal found 12/2$627
This United Airlines deal was found by Cheapflights users on 12/3. 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.
mié. 12/101:34 pmONT - LHR
1 stop12h 06mUnited Airlines
vie. 1/910:00 amLHR - ONT
1 stop19h 58mUnited Airlines
Deal found 12/3$647
This United Airlines deal was found by Cheapflights users on 12/2. 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. 12/91:34 pmONT - LHR
1 stop12h 06mUnited Airlines
mar. 12/1610:05 amLHR - ONT
1 stop15h 32mUnited Airlines
Deal found 12/2$648
This CheapOair deal was found by Cheapflights users on 12/3. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 12/1110:47 amONT - LHR
1 stop15h 13mBritish Airways
lun. 12/157:05 pmLHR - ONT
2 stops26h 50mBritish Airways
Deal found 12/3$657
This Iberia deal was found by Cheapflights users on 12/2. 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.
mié. 12/107:00 amONT - LHR
1 stop19h 00mIberia
dom. 4/121:00 pmLHR - ONT
1 stop18h 40mIberia
Deal found 12/2$662
This United Airlines deal was found by Cheapflights users on 12/3. 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.
jue. 12/111:34 pmONT - LHR
1 stop12h 06mUnited Airlines
jue. 12/1810:05 amLHR - ONT
1 stop15h 38mUnited Airlines
Deal found 12/3$674
This Delta deal was found by Cheapflights users on 12/4. 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.
jue. 12/116:40 amONT - LHR
1 stop22h 10mDelta
lun. 12/152:45 pmLHR - ONT
1 stop16h 02mDelta
Deal found 12/4$698
This United Airlines deal was found by Cheapflights users on 12/2. 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.
jue. 12/111:50 pmONT - LHR
1 stop14h 10mUnited Airlines
lun. 12/221:45 pmLHR - ONT
1 stop16h 56mUnited Airlines
Deal found 12/2$699
This United Airlines deal was found by Cheapflights users on 12/2. 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.
mié. 12/101:34 pmONT - LHR
1 stop12h 06mUnited Airlines
vie. 12/2610:05 amLHR - ONT
1 stop15h 38mUnited Airlines
Deal found 12/2$703
This United Airlines deal was found by Cheapflights users on 12/3. 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. 12/166:00 amONT - LHR
1 stop17h 30mUnited Airlines
vie. 1/93:10 pmLHR - ONT
2 stops29h 07mUnited Airlines
Deal found 12/3$706

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 diciembre 4, 2025.

Most accurate provider

Gotogate
3 stars

Most trusted provider

Gotogate
3 stars

Round-trip from

$557
(oojo)

One-way from

$218
(oojo)

Popular in

December

Cheapest in

September

Average price

$1,034
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. 13% potential increase in price ($113 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 diciembre 4, 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

OntarioGlasgow

ONT - GLA

ONTGLA

Ontario

dom. 2/22

2:47 pm-4:40 pm

2 stops17h 53m

Glasgow Intl

vie. 3/6

11:40 am-10:04 pm

2 stops18h 24m

$556

OntarioGlasgow

ONT - GLA

ONTGLA

Ontario

mié. 2/18

5:06 pm-7:25 pm

2 stops18h 19m

Glasgow Intl

vie. 2/27

6:20 am-10:04 pm

2 stops23h 44m

$580

OntarioEdinburgh

ONT - EDI

ONTEDI

Ontario

vie. 1/16

10:58 am-1:15 pm

2 stops18h 17m

Edinburgh Turnhouse

vie. 1/23

9:55 am-10:13 pm

2 stops20h 18m

$598

OntarioManchester

ONT - MAN

ONTMAN

Ontario

mar. 3/24

5:02 pm-5:35 pm

2 stops17h 33m

Manchester

lun. 3/30

7:45 pm-4:22 pm

2 stops28h 37m

$599

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mar. 1/13

3:30 pm-8:10 pm

2 stops20h 40m

London Heathrow

mar. 1/20

6:20 am-10:51 pm

2 stops24h 31m

$603

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mié. 3/18

12:45 pm-9:00 am

1 stop13h 15m

London Heathrow

mié. 3/25

12:10 pm-9:04 pm

1 stop15h 54m

$605

OntarioGlasgow

ONT - GLA

ONTGLA

Ontario

sáb. 2/7

4:45 pm-5:10 pm

2 stops16h 25m

Glasgow Intl

dom. 2/15

6:35 am-10:04 pm

2 stops23h 29m

$606

OntarioGlasgow

ONT - GLA

ONTGLA

Ontario

sáb. 1/17

3:09 pm-5:10 pm

2 stops18h 01m

Glasgow Intl

sáb. 1/24

6:50 pm-10:13 pm

2 stops35h 23m

$606

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mié. 1/21

6:00 am-9:00 am

2 stops19h 00m

London Heathrow

dom. 1/25

8:40 am-9:05 pm

2 stops20h 25m

$607

OntarioLondon

ONT - LHR

ONTLHR

Ontario

mié. 4/15

11:55 am-2:15 pm

1 stop18h 20m

London Heathrow

mar. 5/5

6:15 am-5:16 pm

2 stops19h 01m

$614

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/3

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 $563). 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 diciembre 4, 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 diciembre 4, 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
8,011 reviews

Crew

8.5

Overall

7.9

Comfort

7.9

Food

7.3

Entertainment

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
8,011 reviews
Delta
7.9
Good
8,011 reviews

Crew

8.5

Overall

7.9

Comfort

7.9

Food

7.3

Entertainment

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
9,063 reviews
Delta
7.9
Good
8,011 reviews

Crew

8.5

Overall

7.9

Comfort

7.9

Food

7.3

Entertainment

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
11,043 reviews
Delta
7.9
Good
8,011 reviews

Crew

8.5

Overall

7.9

Comfort

7.9

Food

7.3

Entertainment

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
3,039 reviews
Delta
7.9
Good
8,011 reviews

Crew

8.5

Overall

7.9

Comfort

7.9

Food

7.3

Entertainment

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
7,559 reviews
Delta
7.9
Good
8,011 reviews

Crew

8.5

Overall

7.9

Comfort

7.9

Food

7.3

Entertainment

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, Delta, and KLM fly from Ontario to United Kingdom in about 13h 15m. The time it takes to get you to your destination can typically vary by up to 7h 25m. Airlines will cover a distance of 5407 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 - 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, 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 $563). 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 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 diciembre 4, 2025.
AirlineCheapestAverageFlexibilityOn-time
DeltaCheapest$543Average$932FlexibilityNo 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$834FlexibilityNo cancel feeOn-time69%

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