the 1928 u.s. national championships (now known as the us open) was a tennis tournament that took place on the outdoor grass courts at the west side tennis club, forest hills in new york, united states. the women's tournament was held from 20 august until 27 august while the men's tournament ran from 10 september until 17 september. it was the 48th staging of the u.s. national championships and the fourth grand slam tennis event of the year.