There is no universal, formal dress code for commercial air travel in 2026, but airlines reserve the right to deny boarding based on safety or public decency. Generally, clothing with offensive language, explicit imagery, or anything deemed overly revealing (exposing private areas) can lead to a gate agent requesting a change of clothes. Bare feet are strictly prohibited on almost all carriers for hygiene and safety reasons. While First Class passengers are no longer required to wear suits, "Business Casual" is still the standard for airline employees traveling on "buddy passes" or standby. For a 2026 traveler, the best "code" to follow is comfort: layers are essential for fluctuating cabin temperatures, and closed-toe shoes are highly recommended by safety experts for better protection during a potential emergency evacuation.