Traditionally, etiquette writers of the past, such as Emily Post, said that white shoes could only be worn between Memorial Day and Labor Day. Today, most style mavens agree that white shoes and clothes are permissible year-round.
White shoes were traditionally associated with summerwear, and the summer season ran from Memorial Day to Labor Day. An exception to this rule was usually made in favor of brides who chose to be married in white outside of the summer season and women, such as nurses, who wore white shoes as part of a uniform. So-called "winter whites" were actually a soft off-white and were used as a way to get around the style rule.