Since the Sainte Chapelle is no longer a consecrated religious building, you don’t need to follow a strict dress code. However, it is still a church, and it is best to avoid ripped jeans, hot pants, shorts, bared midriffs, beachwear, etc. Visitors usually dress up differently – from dinner jackets to casual shirts and jeans. Sainte-Chapelle can get cold in winters because it is not heated, so it is best to dress up in layers.