Every now and then, I see a headline about what to wear to score a free business-class or first-class upgrade on a flight. And every single time, I can’t help but roll my eyes. The truth is this: Airlines have a pretty straightforward system for doling out upgrades, and it has very little to do with what a passenger is wearing.
Each airline has its own hierarchy when it comes to upgrades, but most follow the same general outline. Naturally, paying customers come first—if you want to snag a discounted premium cabin seat, you can ask the agent at the check-in desk if there are any upgrades available. Sometimes you’ll get lucky, and if the cabin has open seats, you might be offered an upgrade for a few hundred bucks. But no, even if you’re dressed to the nines, you won’t get a free upgrade at the desk.
If you want to angle for a free upgrade, there’s only one cardinal rule: acquire elite loyalty status with airlines by flying often. Airlines will typically only offer free upgrades to passengers who are on the official upgrade list, and—you guessed it—you need to have status to be added to that list. So when it comes time to board your plane, the gate agent starts at the top and runs down the list until there are no more seats available. (By the way, it's usually only short-haul and domestic routes that are eligible for complimentary upgrades, so if you're hoping to be bumped up a class on your flight to Paris, don't hold your breath—even the most frequent of flyers don't get those upgrades for free.)
As for who gets the top spot on the upgrade list, each airline has its own set of rules for ranking passengers. But the primary qualification is usually your status tier, followed by the fare class of your original booking. Then there’s the nitty-gritty, such as whether or not you have an airline credit card, if you've booked through a corporate travel partnership, or the specific time you booked your ticket. Some top-tier elites are also given special certificates to bump them to the top of the upgrade list, regardless of all the other ranking factors. And on some airlines, bottom-tier elites actually don’t get free upgrades at all—they have to use miles to add themselves to the upgrade list. But in each and every case of a complimentary upgrade for elites, how fancy you dress has nothing to do with it (though, like all passengers on a flight, you do need to be dressed within appropriate reason—e.g., you can't wear a shirt with profanity on it.)
Now, there is one exception where dressing to impress does matter. Airline employees flying for free as a work perk (they’re called non-revenue passengers or non-revs) might have a company-enforced dress code to follow. While non-revs are eligible for free upgrades from economy to business or first, they’ll have to ensure that they meet their airline’s wardrobe standards, if an official policy exists. That said, these dress codes have relaxed over the years, and many airlines have gotten rid of them entirely, but airline employees are still generally expected to make a good impression while flying.