To look up an inmate in jail, the inmate’s name and the facility where they might be incarcerated are needed. Many jails have search functions on the facility's website where this information can be used to find an inmate.
Many county jails, such as the Los Angeles County Jail, have online inmate locators that can be used to search for an inmate by first and last name. As of 2015, the website also lists a telephone number that can be called to locate an inmate in the Los Angeles County Sheriff’s Department custody. The Harris County, Texas Sheriff’s Department also has a website for online inmate lookup.
Although most inmates in federal prisons have been sentenced, any inmates in federal custody still awaiting trial on other charges may be located by the federal Bureau of Prisons inmate locator on its website. Federal inmates may be searched for by name or prison number. Privately operated websites, such as Jailexchange.com, claim to be able to search all city and county jails in the United States.
Jails or detention facilities are run by the federal, state and local governments. Jails usually house either inmates awaiting trial, inmates who have been sentenced and are waiting to be transferred to a prison or inmates whose sentences are less than one year in length.