Originally Posted by
whitearrow
Barring any weird catastrophes, is 2 1/2 hours enough assuming we're 45 minutes late or so? I'm guessing we'll probably need to change terminals in ORD? Will we have to go back through security?
Terminal 1 and 2 are connected airside (but, as already stated, you'll arrive in Terminal 1; UA exclusively uses Terminal 2 for regional jets). So, even if you did have to change terminals, you'd be fine. The only terminal at ORD that could require re-clearing security is Terminal 5, but UA doesn't use that for departures (there's a bus that stays airside, but AFAIK it's still suspended).
2 1/2 hours is plenty of time for a leisurely connection at ORD. You'd need a minimum of a one-hour delay before I'd even start to be concerned.