She returned to England following four years in Italy and South Africa, and her work was shown and positively received at Royal Academy of Arts exhibitions. After moving to the United States with her husband, Nicholls exhibited her works at the Society of American Artists. She exhibited her work at the Palace of Fine Arts and the Woman's Building at the 1893 World's Columbian Exposition in Chicago, Illinois. She received awards in Europe and the United States, including the Chicago World's Fair, a silver medal in Boston in 1885 for "Venetian Sunlight", and a gold medal at the American Art Association of New York for "Those Evening Bells". Aside from the Chicago World's Fair, Nicholls won medals at many expositions between 1893 and 1904. She preferred working in oils and won the highest honors for her oil paintings. After living in the city for eight years, she was described as "one of New York's best known artists".