Chicago to San Diego — airline reliability comparison
United Airlines is the most reliable airline on the ORD to SAN route with a 80% on-time rate, compared to Frontier Airlines at 42%. Based on 6,002 flights tracked.
This route involves weather-prone airports and high-congestion airports, which can affect reliability regardless of airline.
Source: Bureau of Transportation Statistics. Updated October 2026.| Airline | On-Time % | Cancel % | Avg Delay | Flights |
|---|---|---|---|---|
| United AirlinesUABest | 80% | 0.7% | 64m | 6,002 |
| American AirlinesAA | 71% | 1.2% | 88m | 4,289 |
| Alaska AirlinesAS | 70% | 2.2% | 71m | 777 |
| Frontier AirlinesF9Worst | 42% | 1.8% | 99m | 75 |
Delays, TSA, weather, gates — we'll let you know if something matters.
Data last updated October 2026. Source: Bureau of Transportation Statistics.