Cheap flights from Ontario (ONT)

Inland Empire alternative to LAX, 60 km east of downtown LA

Ontario International serves the Inland Empire and is a popular alternative to LAX for travellers in eastern Los Angeles County, San Bernardino and Riverside. Southwest is the largest carrier, with American, Delta, United, Alaska and Frontier providing competing service. Routes concentrate on western U.S. hubs — Phoenix, Dallas, Denver, Salt Lake City — plus Mexico City via Volaris and Aeromexico.

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Airlines flying from Ontario (ONT)

Major carriers: Southwest, American, Delta, United, Alaska Airlines. Low-cost carriers: Southwest, Frontier, Volaris, JetBlue.

Popular destinations from Ontario (ONT)

Frequently asked questions

What is the cheapest month to fly from Ontario, California?
Mid-January through February and early September are the softest fare months at ONT. Flightmussy's 12-month fare heatmap shows the cheapest week per route, and it is often noticeably cheaper than the same dates from LAX once airport-access costs are included.
Is ONT a better option than LAX?
For travellers east of downtown Los Angeles, yes — ONT avoids the LAX traffic and parking surcharge while offering competitive fares on Southwest, Frontier and the legacy carriers. Flightmussy's multi-airport origin filter lets you compare LAX, BUR, ONT, LGB and SNA in a single free search.
Which airlines fly out of ONT?
Southwest is the dominant carrier, joined by American, Delta, United, Alaska, JetBlue, Frontier, Volaris and Aeromexico. The mix tilts more toward leisure and Mexico routes than LAX. Flightmussy lists every airline side-by-side without account signup.
How far is Ontario Airport from downtown Los Angeles?
ONT sits roughly 60 km east of downtown Los Angeles in San Bernardino County. Without traffic the drive is about 50 minutes; in rush-hour I-10 conditions it can stretch to 90+. Metrolink commuter rail also serves nearby East Ontario station.

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