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Cheap flights from St. Augustine to Ontario (UST - ONT)

UST — ONT
Aug 19 — Aug 261
Tue 8/19
Tue 8/26
1 adult, Economy
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Best time to book a flight from St. Augustine to Ontario

Have a flexible travel schedule? Discover the best time to fly to Ontario from St. Augustine 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 St. Augustine to Ontario

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

Currently, August is the cheapest month in which you can book a flight from St. Augustine to Ontario (average of $246). Flying from St. Augustine to Ontario in March is currently the most expensive (average of $328). 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 UST to ONT?

Find hourly flight availability from St. Augustine to Ontario. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated August 14, 2025.

It’s typically best to fly out from St. Augustine to Ontario in the morning. Doing so could potentially save you 63% on the flight price compared to flying at noon, which is usually more expensive.

Related info for your journey

Find useful and relevant information for your journey from St. Augustine to Ontario. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • Can I find deals for flights from St. Augustine to Ontario that include hotel bookings?

    Yes. In addition to deals on St. Augustine to Ontario flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from St. Augustine to Ontario?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Augustine to Ontario.

  • Can I find deals for business class flights from St. Augustine to Ontario?

    Yes. Cheapflights offers flight deals from St. Augustine to Ontario 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 St. Augustine to Ontario?

    Currently, August is the cheapest month in which you can book a flight from St. Augustine to Ontario (average of $246). Flying from St. Augustine to Ontario in March is currently the most expensive (average of $328). 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.

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