I know, of course, that Thanksgiving is not a holiday in the U.K. It's one of the busiest flight weekends in the US, though. In checking when to use our FF miles, we can get good flights from LGW to DFW and then to Portland, OR on Thursday Nov 22.
Is DFW likely to be a zoo on Thanksgiving? I'm thinking (hoping) that most people will be flying the days before and after the holiday, and that this might be an OK time.

I have flown within the US on Turkey day. But it was on small airline SWest.
I have to say the airport LAX ?phoenix was a zoo..

It sort of depends - the Wed. is the busiest travel day of the year. Thurs a.m. can still be pretty busy w/ folks who couldn't get out Wed afternoon. But if you are connecting through DFW on Thurs afternoon you will probably be fine. By then most everyone is sitting down to eat. The Sunday is also a "zoo" day.

(BTW, southwest is not a "small" airline)

I believe Sunday after Thanksgiving is the busiest day of travel, including air travel, in the US. People may leave home on Mon, Tue, Wed and even Thurs; but they all go home on Sunday.

We've flown on Thanksgiving day quite a few times. My impression has generally been that it is a bit quieter than the average holiday travel day, and we fly out of O'Hare. That said, we flew out of ORD on the Wednesday evening before Thanksgiving last year, and we kept asking where all the people were--it was really quiet. Maybe they were traveling on Thursday??

We just did the LGW/DFW connection a few weeks ago...and I have to say I felt like I walked 3 miles to get to the immigration agent. They had switchback lines and about 400 people waiting. I thought O'Hare was bad but DFW beats them! Never again if I can help it.

Thanksgiving Day (Thursday) isn't bad at all but every other day that week will be really busy.

<<Thanksgiving Day (Thursday) isn't bad at all but every other day that week will be really busy.>>

It's my favorite day to fly, much quieter than the rest of the week and usually plenty of empty seats to spread out.