$103 Cheap Frontier Airlines flights Ontario (ONT) to Miami (MIA)

Scoring cheap one-way Frontier Airlines flights from ONT to MIA from $103 on Expedia is easy — just filter by "Price (lowest to highest)." Or check out our affordable return fares from $206 for your next exciting adventure.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.

For cheap Frontier Airlines fares from Los Angeles - Ontario Intl. Airport (ONT) to Miami Intl. Airport (MIA), start searching one to three months before your intended departure. Reserving domestic flights 34 to 86 days in advance could save you 25% compared to booking just 6 to 12 days ahead. The day you book can also impact the cost. Sunday tends to be the most affordable, while Monday is often the most expensive for domestic flights. You can save 6% on average by booking your trip on a Sunday.**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.

Filter your results by "Morning" and "Early Morning" to see the earliest flights from ONT to MIA. Heading off early means you're less likely to experience cancellations.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.

A rewarding loyalty program and the ability to collect points through Frontier Miles are the start of the reasons to leave from ONT to MIA with Frontier Airlines. Plus, when you join our One Key™ program, you can receive OneKeyCash™* alongside any airline loyalty program earnings. It's yours to spend on your next adventure.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.