White is traditionally associated with many quinceañera dresses in older customs.
White and pastel dresses were widely used for formal quinceañera celebrations, particularly when the event included a Catholic church service. The color helped create a formal, youthful appearance and could visually distinguish the celebrant from her court.
There is no universal rule requiring a white dress. Contemporary celebrants often choose pink, blue, red, purple, gold, or other colors, and some wear a second dress for the reception. Fashion, family preference, local custom, and religious practice all influence the choice.
White should also not be interpreted as proof that a quinceañera is a wedding. The two celebrations can share formal clothing and ceremonies, but a quinceañera marks a fifteenth birthday rather than a marriage.