Is 45 minutes enough to connect at ORD?

Probably not. ORD (Chicago O'Hare) is one of the largest airports in the U.S. with four terminals, and 45 minutes is extremely tight for most connections — especially if you're changing terminals.

BTS data shows that flights arriving at ORD are delayed an average of 12 minutes, and roughly 23% of passengers with 45-minute connections at ORD miss their connecting flight. That miss rate drops to about 8% at 60 minutes and under 3% at 90 minutes.

If your flights are both on the same airline in the same terminal (e.g., both United in Terminal 1), and your inbound flight arrives on time, 45 minutes is technically possible — gates in the same terminal are usually a 5-10 minute walk. But any delay on your first flight, any gate change, or a terminal switch (especially to Terminal 5 international, which requires leaving security) makes it nearly impossible. The airline minimum connection time (MCT) at ORD is 75 minutes domestic and 120 minutes international for a reason.