Southwest Airlines Flights from Ontario to Phoenix

Southwest Airlines on this route

Phoenix is a Southwest Airlines hub, so Southwest Airlines typically offers several daily departures on ONT–PHX, with nonstop service where demand supports it and connections through its other hubs otherwise. The nonstop flight time is about 1h 21m.

Fare classes available: Basic, Choice / Choice Preferred, Choice Extra. Southwest does not charge change fees on any fare; you pay the fare difference if the new flight is more expensive.

Recorded lows on ONT–PHX start at $125 one-way ($191 round-trip). That figure comes from cached search data and moves with demand, so treat it as a benchmark for what a good price looks like rather than a guaranteed fare.

Delta Air Lines and United Airlines both operate hubs at one end of this route, so nonstop or single-connection service is usually available, along with American Airlines and Southwest Airlines. Our agents can book any of them and compare fare classes side by side.

This is a 324 miles flight, short enough that boarding takes almost as long as the cruise. Fares on hops like this are driven less by season and more by day of week; midweek departures can be half the Friday price.

When to fly

West Coast and Mountain departures spike over summer holidays and the December break; January (after New Year), late April, May, and September are usually the cheapest windows.

On this specific route our fare history shows September as the cheapest month and November as the most expensive, a spread of $66 between the two.

Midweek travel almost always beats weekends on price here. If your dates are flexible by a day or two, tell the agent; shifting a Friday departure to Thursday or a Sunday return to Monday is the single most reliable way to cut the fare.

For domestic travel, booking three to eight weeks ahead usually captures the best price. Inside two weeks, fares climb; more than four months out, airlines have not yet released their cheapest inventory.