Rockwall County is part of the Dallas-Fort Worth-Arlington metropolitan statistical area.

Rockwall County also is home to the great rock wall, which is no longer in public view today.

By the 2020 census, its population increased to 107,819 with a racial and ethnic makeup of 65.11% non-Hispanic Whites, 7.59% African Americans, 0.44% Native Americans, 3.07% Asians, 0.07% Pacific Islanders, 0.32% some other race, 4.34% multiracial, and 19.07% Hispanic or Latino of any race.

[11] The United States Census Bureau estimated that in 2023, Rockwall County’s population was 131,307, and the county was 21.4% Hispanic or Latino, with non-Hispanics consisting of 62.1% White, 9.9% Black, 3.8% Asian, 0.5% Native American, 0.1% Pacific Islander, and 2.1% multiracial.

The 1968 election was highly transitional for the county, with Hubert Humphrey only winning with 39% of the vote due to the strong third-party candidacy of George Wallace.

George H. W. Bush in 1992 has been the only Republican to fail to win a majority in the county since then, as the strong third-party candidacy of Ross Perot that year led him to a second-place finish in the county over national winner Bill Clinton.