Flight Check

Best Airline: SFO to ONT

San Francisco to Ontario — airline reliability comparison

United Airlines is the most reliable airline on the SFO to ONT route with a 83% on-time rate, compared to Frontier Airlines at 70%. Based on 2,068 flights tracked.

This route involves high-congestion airports, which can affect reliability regardless of airline.

Source: Bureau of Transportation Statistics. Updated October 2026.

On-Time Rate by Airline

United Airlines83%
SkyWest Airlines81%
Frontier Airlines70%

SFO to ONT Airline Comparison

AirlineOn-Time %Cancel %Avg DelayFlights
United AirlinesUABest83%0.8%57m2,068
SkyWest AirlinesOO81%1.7%61m2,006
Frontier AirlinesF9Worst70%1.8%86m899

Route Overview

81%
Overall On-Time
68m
Avg Delay
1.2%
Cancel Rate
5,026
Total Flights
SFO to ONT Route DetailsReturn: ONT to SFO
SFO AirportONT Airport

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Data last updated October 2026. Source: Bureau of Transportation Statistics.