Why do bras leave marks on skin?

Bras leave marks on skin primarily due to concentrated pressure and friction from poorly fitting bands and straps that create uneven load distribution across your body. Most marks occur when bands dig in, straps carry too much weight, or fabric rubs against skin, especially when heat and moisture amplify the friction during daily movement.

Well-designed bras with wider bands, thoughtful strap placement, and proper sizing distribute pressure evenly to prevent these concentrated pressure points that indent or irritate skin. Additionally, some people experience reactions to certain materials like elastics, dyes, or metal hardware, which can create persistent red patches that mimic pressure marks. The good news is that marks serve as valuable feedback about fit and design. When your bra truly works for you, it should feel like a supportive hug without leaving a trace on your skin. If it doesn't, you should try a new size or style.