Cheap flights from North America to Los Angeles from $44

In general, September is the cheapest month to fly from North America to Ontario. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $287. If you aren’t able to travel during the month of September, then book flights to Ontario from North America during October instead. Flights to Ontario in October, while not as cheap as those in September, still average around $287.

The cheapest day to depart on your flight to Ontario is on a Friday when prices can be found for as low as $309. This is often the case because there is less demand to fly during this day of the week. When flying out on a Monday, the most expensive travel day of the week, you can expect to see flight prices from North America to Ontario for around $447.

In the afternoon is the cheapest time of day to fly from North America to Ontario when you can find flight prices for as low as $336. Flying to Ontario in the afternoon is an ideal time because this is during off-peak travel hours. If you have a flexible travel schedule, then try to avoid flying in the evening when prices are $337 on average. Flights to Ontario from North America in the evening are generally more expensive because this time of day is more convenient for travelers’ schedules.

Fly from Las Vegas Harry Reid Intl to Ontario for the best North America - Ontario flight prices

You are more likely to see cheaper flights to Ontario from North America when booking weeks ahead of your departure date. In general, you can expect to find flights to Ontario for around $381 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Ontario from North America for as low as $168 on momondo.

There are 4 cabin classes available to choose from on North America to Ontario flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Southwest, United Airlines, and Frontier are the most popular carriers operating from North America to Ontario

Frontier, United Airlines and American Airlines are the top three most popular airlines that fly to Ontario from North America according to our data. Frontier is the first choice among our users, with 30% of people opting to fly with this airline when traveling to Ontario. Keep in mind that there are 14 different airlines that fly to Ontario on a routine basis, so you have a few additional options to choose from.

As of April 2026, there are 43 flights per day flying from North America to Ontario. The most common time of day flights depart is 9:00PM, with 38% of flights taking off in the evening.

307 flights are operational weekly from North America to Ontario as of April 2026. The most popular departure day for this route is Fri, with 19% of flights per week taking off on this day.