San Francisco to Chicago

What the Data Says About SFO to ORD

The San Francisco to Chicago corridor (SFO → ORD) covers roughly 1,846 miles and is served by 8 carriers, based on Bureau of Transportation Statistics reporting. Across 26,450 flights in the dataset, this route posts a 83.8% on-time rate with an average delay of 74.8 minutes when flights run late. Over the most recent 24 months of BTS data, 10,321 flights were recorded on this pairing — 131 cancelled (1.3%) and 32 diverted (0.3%). Those baseline metrics tell you what to expect before you book.

Having 8 carriers on the route matters: more carriers generally means more daily schedule options, competitive pricing, and redundancy when flights are cancelled. With 26,450 total flights analyzed, the 83.8% on-time figure is statistically meaningful rather than a small-sample fluke. The 74.8-minute average delay applies only to flights that actually ran late, so it is not the average wait across all departures — the majority of flights on this route depart on time under the BTS definition of a delay (15+ minutes past schedule).

Looking at recent months, Apr 2025 posted the best performance on this corridor at 87% on-time, while Jul 2024 came in at 69% on-time — a 18-point gap between best and worst recent month. For travelers evaluating the SFO to ORD route, the combination of a 83.8% on-time rate, 74.8-minute average delay, 1.3% recent cancellation rate, and 8 available carriers is the concrete summary of what BTS data shows about reliability on this pairing.