Peltz was born in Westchester County, New York. Her mother, Claudia (née Heffner), is a former model and her father, Nelson Peltz, is a billionaire businessman. She has four older brothers, two younger brothers, and an older sister; two of her brothers are actor Will Peltz and ice hockey defenceman Brad Peltz. She also has two half-siblings from her father's previous marriages. Her father is of Austrian-Jewish and Russian-Jewish descent, while her mother has Italian, German, Welsh, and English ancestry. The New York Times has described Nicola's parents as "compassionate leaders of the New York Jewish community. "