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For most of us, what you wear on the airplane is an assortment of what’s clean, what’s not packed, and what is comfortable enough to wear for a six-hour flight on a flying sardine can. However, there are a few good reasons to step out of the yoga pants and sweatshirts and into a more polished, tailored look.

First of all, as anyone who has fixed their make-up and put on a clean shirt before heading to the Piggly Wiggly can attest—dressing up just makes you feel better. It’s a way of presenting a civilized face to world—even if you nearly missed your flight after staying up all night watching Designing Women re-runs.

If being a good-looking member of society isn’t enough of a reason to swap sweats for dress slacks, remember that many airlines have dress codes. While most airlines have clothing standards for their own flight crews, as well as their friends and families, when they are flying on one of the passes that airlines give to staff as a perk, which lets friends or relatives of airline employees fly free or at discounted rates. That is what happened to two teenage girls who wore leggings for their United Airlines flight this spring, and were denied boarding onto the plane.

As The New York Times points out, while it’s not frequently enforced, many airlines have dress codes for passengers, too. United’s policy lets them turn away passengers who are “not properly clothed,” and American Airline’s policy says that they may refuse to transport passengers “clothed in a manner that would cause discomfort or offense to other passengers.”

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Dressing up for the plane is also a sign of respect to the other members of your community that have to look at you as make your way through security or loiter in the aisles of the plane. It’s also a signal to the hard-working men and women helping to ensure that you arrive safely at your destination that you respect their workplace. That sign of respect can possibly lead to a smile and occasionally even greater rewards, too. Flight crew members can upgrade passengers who look particularly snazzy. George Hobica, founder of the travel fare advice site Airfare Watchdog, told the Times that “everyone believes no one gets upgraded anymore based on how they look.” But, he added, “It does happen.” However, your chances of scoring a free upgrade to business class are all dependent on looking the part.

[H/T Lifehacker]