Find flights
Deals

£57+ Cheap flights from Ontario

This is the cheapest return flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 3/6. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
ONT — LHR
29 Apr — 6 May1
1 adult
1 adult, Economy, 0 bags

Find flights from Ontario within your budget

 
Find flights departing from Ontario that match your specified budget. Filter results by price range, allowing you to narrow down options and find flights that fit within your financial constraints. Please note that the search results are based on data from user searches, with fares last updated on 30 March 2026. In the last 7 days, Cheapflights users made a total of 858,174 searches

Fly to

Route

Depart

Return

Price

Cheapest return flight

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Tue 28/4

10:39-13:30

Nonstop2h 51m

Seattle/Tacoma Intl

Sat 2/5

07:05-09:45

Nonstop2h 40m

£149

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Thu 7/5

10:39-13:30

Nonstop2h 51m

Seattle/Tacoma Intl

Sat 9/5

19:50-22:32

Nonstop2h 42m

£156

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Fri 24/4

17:55-20:55

Nonstop3h 00m

Seattle/Tacoma Intl

Mon 27/4

08:25-11:13

Nonstop2h 48m

£164

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Thu 7/5

15:00-20:05

1 stop5h 05m

Seattle/Tacoma Intl

Tue 12/5

11:40-21:30

2 stops9h 50m

£172

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Tue 5/5

10:39-13:30

Nonstop2h 51m

Seattle/Tacoma Intl

Wed 6/5

11:36-14:30

Nonstop2h 54m

£179

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Wed 6/5

14:20-17:24

Nonstop3h 04m

Seattle/Tacoma Intl

Fri 15/5

08:25-11:12

Nonstop2h 47m

£186

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Mon 27/4

06:00-08:50

Nonstop2h 50m

Seattle/Tacoma Intl

Mon 4/5

21:24-14:19

1 stop16h 55m

£219

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sat 2/5

07:00-14:55

1 stop7h 55m

Seattle/Tacoma Intl

Sun 3/5

07:05-09:45

Nonstop2h 40m

£226

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Thu 24/9

17:05-22:05

1 stop5h 00m

Seattle/Tacoma Intl

Sun 27/9

10:00-12:49

Nonstop2h 49m

£247

OntarioSeattle

ONT - SEA

ONTSEA

Ontario

Sun 26/4

06:00-08:50

Nonstop2h 50m

Seattle/Tacoma Intl

Tue 28/4

19:50-22:32

Nonstop2h 42m

£247

Flights are sorted by cheapest return flights first.

Deals found on 26/3

Showing 1-10 of 60 resultsSorted by cheapest first
1
2
3
...
6

Best time to book a flight from Ontario

Have a flexible travel schedule? Discover the best time to fly from Ontario with our price prediction graph.
Estimated return 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.

Travel insights for flights from Ontario

Get recent, data-driven insights about flights from Ontario including ideal travel times, pricing trends, and more.

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

Currently, December is the cheapest month in which you can book a flight from Ontario (average of £354). Flying from Ontario in June will prove the most costly (average of £527). There are multiple factors that influence the price of a flight so comparing airlines, departure airports and times can help keep costs down.

What are popular destinations to fly to from Ontario?

If you’re flying from Ontario, these routes are more frequently taken by airlines Seattle (104 flights per day), Dallas (99 flights per day) and Phoenix (82 flights per day).

Portland
Portland
From £65
Dallas/Fort Worth
Dallas/Fort Worth
From £225
Honolulu
Honolulu
From £147
Charlotte Douglas
Charlotte Douglas
From £128

What is the cheapest place to fly to from Ontario?

The cheapest city to fly to from Ontario is Portland, with prices starting at £65. Explore other affordable destinations below.

Portland
Portland
From £65
Charlotte Douglas
Charlotte Douglas
From £128
Honolulu
Honolulu
From £147
Dallas/Fort Worth
Dallas/Fort Worth
From £225

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Related info for your journey

Access useful and relevant information related to your journey from Ontario. This can include details such as airport transportation, visa requirements, travel insurance, luggage regulations, and any other information that can ensure a smooth and hassle-free travel experience. Please note that the information is based on general guidance and may need to be verified with official sources. Data last updated 30 March 2026.

  • What are the most popular destinations to fly to from Ontario?

    This month, the top selected destinations from Ontario are Las Vegas, Dallas/Fort Worth Airport, Denver. Throughout the year, Las Vegas, Dallas/Fort Worth Airport, Denver are some of the top choices made by users flying from Ontario.

  • What is the cheapest flight from Ontario to anywhere?

    Users have flown out of Ontario for as low as £65 to Portland (prices may vary depending on the airline and departure time). On average, users have booked flights for £262 to fly from Ontario.

  • What is the cheapest month to fly from Ontario?

    At the present moment the cheapest month to fly from Ontario is currently December; with June being the most expensive. Prices will vary depending on multiple factors such as booking in advance, airline and departure airports and times.

  • Where are the cheapest places to fly to from Ontario?

    Check out the cheapest flights from Ontario to embark to:
    Travel from Ontario to London from £673 round trip

  • How does Cheapflights help users find flights from Ontario?

    Deals for flights from Ontario are sourced from 900+ travel sites when you use Cheapflights. When all flight results come back, Cheapflights lets you sort and filter flights using different criteria to choose to your preference, such as price, airport, cabin class, and plenty of other options.

  • Why should you use Cheapflights to find cheap flight tickets from Ontario?

    It’s simple! Cheapflights, which is free to use for everyone, saves millions of users time and money every year by helping them find the cheapest and most suitable flights from Ontario.

  • Can Cheapflights find flights from Ontario with no change fees?

    Yes! Cheapflights helps users easily find flights from Ontario with no change fees.

  • Can Cheapflights notify me if prices for flights from Ontario become cheaper?

    Yes, Cheapflights has a feature called Price Alerts, which offers users the ability to be notified when flight prices change. Track prices for your flight from Ontario today and book when you’re ready!

See more FAQs

Fly with Cheapflights

Find the best flight deals on Cheapflights, where travellers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from Ontario?

Deals for flights from Ontario are sourced from 900+ travel sites when you use Cheapflights. When all flight results come back, Cheapflights lets you sort and filter flights using different criteria to choose to your preference, such as price, airport, cabin class, and plenty of other options.

Why should you use Cheapflights to find cheap flight tickets from Ontario?

It’s simple! Cheapflights, which is free to use for everyone, saves millions of users time and money every year by helping them find the cheapest and most suitable flights from Ontario.

Can Cheapflights find flights from Ontario with no change fees?

Yes! Cheapflights helps users easily find flights from Ontario with no change fees.

Can Cheapflights notify me if prices for flights from Ontario become cheaper?

Yes, Cheapflights has a feature called Price Alerts, which offers users the ability to be notified when flight prices change. Track prices for your flight from Ontario today and book when you’re ready!

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.