I'm thinking of flying from IAD-LHR on a yet-to-be-determined date, leaving on the 9:35 a.m. departure to avoid jetlag upon arrival in London.

Considering how long the check-in lines have been at Dulles most mornings lately (even for the 1K/UGS line...walking past the masses in the general line is hard enough) I'd like to check in at my home airport of CHO, Charlottesville, VA, the morning of departure rather than at IAD. I drive right by CHO on the way to IAD---it's about an hour and 45 minutes from door to door---so it'll undoubtedly be faster to check in at the smaller airport than brave the lines at IAD.

If I flew out of CHO on UAX, the fare would be $167 more r/t...just not worth it to me especially considering that I'd have to brave the dreaded terminal G at IAD for my connecting flights.

So is it permissible to check in for a United flight at an airport different from one's point of departure? The CHO agents could obviously check me in for the IAD-LHR segment if I were flying CHO-IAD to connect, but how about for an itinerary originating at IAD?