The Cannes Film Festival’s red carpet has always been fashion’s most renowned battlefield. Over time, the place has become a fashion runway rather than a cinematic interest, where celebrities and now influencers compete to deliver viral couture moments with a dramatic edge. But in 2026, the rules are tighter than ever, with organisers reportedly releasing codes of conduct with more practical choices, allowing the focus to be on the cinema itself. Here are five major fashion rules celebrities and influencers absolutely cannot ignore at Cannes Film Festival 2026.