Nine incorporated cities within the county (Del Mar, Encinitas, Imperial Beach, Lemon Grove, Poway, San Marcos, Santee, Solana Beach, and Vista) contract with the office for municipal law enforcement and public safety services.

The Wireless Services Division is responsible for the day-to-day operations of the San Diego County–Imperial County Regional Communications System.

The San Diego County Sheriff's Department was a co-appellant in the Supreme Court of the United States and Ninth Circuit cases Kolender v. Lawson, 461 U.S. 352 (1983),[4][5] which held unconstitutional laws that allow law enforcement to demand that "loiterers" and "wanderers" provide identification; this continues to affect other offices nationwide.

[6][7][8] On September 10, 2024, the agency's official name was changed to the San Diego County Sheriff’s Office.

Today, the San Diego County Sheriff's Office utilizes the Ford Explorer as their base model for their fleet.