Wildomar is in Riverside County, in the Riverside-San Bernardino metro area.

The community name combined portions of three founders' first names: William Collier, Donald Graham and Margaret Collier Graham

The latitude of Wildomar is 33.598N. The longitude is -117.279W. It is in the Pacific Standard time zone. Elevation is 1,270 feet.

The population, at the time of the 2000 census, was 14,064.