$45 Find cheap flights from California to Ontario

KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from California to Ontario.

KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Ontario from California is likely to change within 7 days, so travelers know whether to wait or book now.

Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Ontario with an airline and back to California with another airline.

Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Ontario from California up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.