Bloomington is a census-designated place in San Bernardino County, California, United States. The population was 23,851 at the 2010 census, up from 19,318 at the 2000 census.Though now unincorporated, many of the town's political activists are pushing for Bloomington to attain cityhood, while the nearby cities of Rialto and Fontana are attempting to annex the community. The incorporation effort is led by the BIC, the Bloomington Incorporation Committee.