$114 Cheap Frontier Airlines flights Milwaukee (MKE) to Ontario (ONT)

Grab cheap return Frontier Airlines flights from $228 from MKE to ONT by organizing your results from “Price (lowest to highest)” on Expedia. Or search for deals from $114 for a one-way trip.**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.

January is one of the cheapest months to jet off to Ontario with Frontier Airlines. You could also find fantastic deals on one-way and return fares in April.

Begin your search one to three months before your departure to find cheaper fares on Frontier Airlines flights from General Mitchell Intl. Airport (MKE) to Los Angeles - Ontario Intl. Airport (ONT). You can save 25% by booking your domestic flight 34 to 86 days in advance versus last-minute reservations made 6 to 12 days out. You could also cut costs by buying your fare on a Sunday, as it’s 6% cheaper on average than a Monday, the most expensive day to book.* Get your timing spot on, and you can enjoy significant savings on domestic trips.*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.

To see if there’s a direct trip from MKE to ONT with Frontier Airlines or other carriers, check the “Nonstop” box when looking for flights.

Filter your results by “Morning” and “Early Morning” to see the earliest flights from MKE to ONT. Jetting 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.

Board a Frontier Airlines flight from General Mitchell Intl. Airport (MKE) to Ontario, and you’re most likely to touch down at Los Angeles - Ontario Intl. Airport (ONT). This is the airline’s primary hub here.

Depart from MKE to ONT with Frontier Airlines and look forward to a host of benefits starting with a rewarding loyalty program. When you book through Expedia as a Frontier Miles and One Key™ member, you could also earn OneKeyCash™* to use on select future travel purchases.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.

It’s usually possible to cancel or modify your flight, although there may be a charge if your booking was made more than 24 hours ago. Need to keep your options open? Make use of our “Changes included” and “No cancel fee” filters to find flights that won’t charge extra if you have to adjust your plans. To update your itinerary, go to “Trips,” select your flight and click on “Manage Booking” for more information.