While one or two bobby pins won't make a difference, if you have a head-full — or even hand-full — of bobby pins in your hair, that'll be enough to set off the metal detectors at airport security.

In 2026, a single bobby pin is highly unlikely to set off an airport metal detector, but a cluster or "head-full" of them certainly can. Modern walk-through metal detectors (WTMD) are designed to detect a specific mass of metal; while the small amount of steel in one or two pins is below the threshold, having 10 or 20 pins in a complex hairstyle can trigger an alarm. This often leads to a "secondary screening" where a TSA or security officer will use a handheld wand to pinpoint the metal and may perform a "hair pat-down" to ensure no prohibited items are hidden. If you are wearing a "top-knot" or "updo" with many pins, the "gold standard" for a fast transit is to inform the officer beforehand or use plastic/resin hair clips instead of metal pins. Notably, high-quality gold or silver jewelry usually passes through without issue, but the "conductive" nature of the cheap steel used in bobby pins is exactly what the sensors are tuned to find. To avoid delays, keep your hair accessories minimal and be prepared for a quick manual inspection if your style is metal-heavy.