Cheap flights from San Francisco to Ontario from $145

The month of January is, on average, the cheapest month to fly to Region of Ontario from San Francisco, with most prices found around $392. If you aren’t able to travel during the month of January, then book flights to Region of Ontario from San Francisco during June instead. Flights to Region of Ontario in June, while not as cheap as those in January, still average around $401.

According to our data, Tuesday is the cheapest day to fly to Region of Ontario from San Francisco. The lowest ticket price found for a Tuesday departure recently was $558. Keep in mind that prices can always vary depending on your route and whether or not you are flying domestic or international. Flights from San Francisco to Region of Ontario on a Sunday will generally be more expensive and average around $677. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.

According to our data, the cheapest time of day to fly to Region of Ontario is at noon. momondo users have found flights departing from San Francisco to Region of Ontario at noon for as low as $455. Keep in mind that these prices may fluctuate based on what airline you choose and the time of year you plan to travel. Flights in the morning are often more expensive with an average ticket price of $691.

Fly from San Francisco to Toronto Pearson Intl for the best San Francisco - Ontario flight prices

You are more likely to see cheaper flights to Region of Ontario from San Francisco when booking weeks ahead of your departure date. In general, you can expect to find flights to Region of Ontario for around $450 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Region of Ontario from San Francisco for as low as $382 on momondo.

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

WestJet, United Airlines, and Delta are the most popular carriers operating from San Francisco to Ontario

Air Canada, Porter Airlines and United Airlines are the top three most popular airlines that fly to Region of Ontario from San Francisco according to our data. Air Canada is the first choice among our users, with 43% of people opting to fly with this airline when traveling to Region of Ontario. Keep in mind that there are 8 different airlines that fly to Region of Ontario on a routine basis, so you have a few additional options to choose from.

The number of flights available between San Francisco and Region of Ontario is 24 per day as of March 2026. The most frequent departure time is 8:00AM, with 50% of daily flights leaving at noon.

The number of flights available between San Francisco and Region of Ontario is 173 per week as of March 2026. The most frequent departure day is Mon, with 16% of weekly flights leaving on this day.