41 destinations have scheduled flights from ONT, about 666 departures a week. Weekly frequencies come from airline schedules and observed departures, not live status.
| Destination | Flights per week | Airlines | Typical duration |
|---|---|---|---|
| Phoenix (PHX) | 82 | Southwest Airlines Co., American Airlines, Envoy Air Inc. | — |
| Las Vegas (LAS) | 58 | Southwest Airlines Co., Frontier Airlines, Inc. | — |
| Seattle-Tacoma International (SEA) | 52 | Alaska Airlines, Delta Air Lines | — |
| Sacramento (SMF) | 51 | Southwest Airlines Co. | — |
| Denver International (DEN) | 38 | Southwest Airlines Co., United Airlines, UPS Airlines, Frontier Airlines, Inc. | — |
| Oakland (OAK) | 35 | Southwest Airlines Co., Federal Express | — |
| Dallas/Fort Worth International (DFW) | 32 | American Airlines, Frontier Airlines, Inc., UPS Airlines | — |
| San Francisco International (SFO) | 32 | United Airlines, Frontier Airlines, Inc. | — |
| Honolulu International (HNL) | 26 | Air Transport International Inc., Alaska Airlines, ALS, UPS Airlines | — |
| San Jose (SJC) | 26 | Southwest Airlines Co. | — |
| Portland International (PDX) | 25 | Alaska Airlines, UPS Airlines | — |
| Salt Lake City International (SLC) | 24 | Delta Air Lines | — |
| Hartsfield-jackson Atlanta International (ATL) | 18 | Delta Air Lines | — |
| Louisville International (Standiford Field) (SDF) | 14 | UPS Airlines, ALS | — |
| Baltimore/Washington International Thurgood Marshall (BWI) | 12 | Southwest Airlines Co. | — |
| William P Hobby (HOU) | 12 | Southwest Airlines Co. | — |
| Kahului (OGG) | 12 | Air Transport International Inc., UPS Airlines | — |
| Santa Rosa (STS) | 12 | American Airlines, Alaska Airlines | — |
| Taipei (TPE) | 11 | China Airlines, Jett8 Airlines Cargo | — |
| Charlotte Douglas (CLT) | 9 | American Airlines | — |
| Fort Worth Alliance (AFW) | 7 | Air Transport International Inc. | — |
| Boise Air Terminal/Gowen Field (BOI) | 7 | Alaska Airlines | — |
| Don Miguel Hidalgo y Costilla International (GDL) | 7 | Volaris | — |
| Los Cabos (SJD) | 7 | Volaris | — |
| Kona International Airport (KOA) | 5 | UPS Airlines | — |
| Memphis (MEM) | 5 | Federal Express | — |
| Greater Rockford Airport (RFD) | 5 | UPS Airlines | — |
| Del Bajío International (BJX) | 4 | Volaris | — |
| Indianapolis International (IND) | 4 | Federal Express | — |
| Midway (MDW) | 4 | Southwest Airlines Co. | — |
| Miami International Airport (MIA) | 4 | UPS Airlines | — |
| El Salvador International (SAL) | 4 | AVIANCA | — |
| Boeing Field/King County International Airport (BFI) | 3 | UPS Airlines | — |
| Love Field (DAL) | 3 | Southwest Airlines Co. | — |
| Piedmont Triad International (GSO) | 3 | UPS Airlines | — |
| George Bush Intercontinental (IAH) | 3 | Frontier Airlines, Inc. | — |
| Francisco J. Múgica Internacional (MLM) | 3 | Volaris | — |
| Logan International (BOS) | 2 | UPS Airlines | — |
| Newark Liberty International (EWR) | 2 | UPS Airlines | — |
| Orlando International (MCO) | 2 | UPS Airlines | — |
| Ted Stevens Anchorage International Airport (ANC) | 1 | UPS Airlines | — |
GET /routes returns each scheduled flight from ONT: airline, flight number, departure and arrival time, duration, days of operation and aircraft type.
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