The 1890 U.S. National Championships was a tennis tournament that took place from June to August 1890. The women's singles and doubles competitions were held from June 10 to June 13 on the outdoor grass courts at the Philadelphia Cricket Club in Philadelphia, Pennsylvania. The men's singles and doubles competitions were held from August 18 to August 27 on the outdoor grass courts at the Newport Casino in Newport, Rhode Island. It was the 10th U.S. National Championships and the second Grand Slam tournament of the year. US Open 1890: August 18–18, 1890. Men's singles: Oliver Campbell. Women's singles: Ellen Roosevelt. Wiki link