Flight Check

Best Airline: ONT to SFO

Ontario to San Francisco — airline reliability comparison

United Airlines is the most reliable airline on the ONT to SFO route with a 80% on-time rate, compared to Frontier Airlines at 57%. Based on 2,066 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 Airlines80%
SkyWest Airlines71%
Frontier Airlines57%

ONT to SFO Airline Comparison

AirlineOn-Time %Cancel %Avg DelayFlights
United AirlinesUABest80%0.8%65m2,066
SkyWest AirlinesOO71%1.5%83m2,008
Frontier AirlinesF9Worst57%2.4%70m900

Route Overview

73%
Overall On-Time
71m
Avg Delay
1.3%
Cancel Rate
5,026
Total Flights
ONT to SFO Route DetailsReturn: SFO to ONT
ONT AirportSFO Airport

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