We have previously mentioned that we do not condone traveling in sweatpants.  Sure, they're soft and cushy, but there are better, more sophisticated options, that are just as comfortable AND have pockets where you can keep your ID, and boarding pass.

Jeans please!  With myriad options, there is really no excuse not to have at least one decent pair in which you could travel. 

Earnest Sewn - these are the softest, most comfortable - not to mention flattering - jeans.  The lighter wash makes them more casual, but not as casual as sweats.

Ali Flare Jean - Retail $215, on sale at Shopbop for $107.50

Joe's - these aren't quite as stretchy, but have a more sophisticated, trouser-type look, and a higher rise.

Joe's Jeans Muse Wide Leg - $159 at Shopbop

7 For All Mankind - the originator of the overpriced high-end, designer jean, 7's set the bar.  These are their original recipe - stay away from the extra-crispy:

7 For All Mankind Bootcut Stretch Jean - $155 at Nordstrom

AG - the black wash skinny jean is perfect for a slightly dressier look that can easily pair with jeans.

AG Jeans The Stilt in Coated Black - $168 at Revolve Clothing

There are more where these came from.  Explore at your leisure, and please, leave the sweats at home.