In the United States, the federal civil service was established in 1871.

The Federal Civil Service is defined as "all appointive positions in the executive, judicial, and legislative branches of the Government of the United States, except positions in the uniformed services." (5 U.S.C. § 2101). In the early 19th century, positions in the federal government were held at the pleasure of the president—a person could be fired at any time. The spoils system meant that jobs were used to support the American political parties, though this was gradually changed by the Pendleton Civil Service Reform Act of 1883 and subsequent laws. By 1909, almost two-thirds of the U.S. federal workforce was appointed based on merit, that is, qualifications measured by tests. Certain senior civil service positions, including some heads of diplomatic missions and executive agencies are filled by political appointees. Under the Hatch Act of 1939, civil servants are not allowed to engage in political activities while performing their duties.

According to the Office of Personnel Management (OPM), as of December 2011, there were approximately 2.79 million civil servants (civilian, i.e. non-uniformed) employed by the US Government.(This includes executive, legislative and judicial branches of government. This also includes more than 600,000 United States Postal workers.)

The U.S. civil service includes the Competitive service and the Excepted service. The majority of civil service appointments in the U.S. are made under the Competitive Service, but certain categories in the Diplomatic Service, the FBI, and other National Security positions are made under the Excepted Service. (U.S. Code Title V)

U.S. state and local government entities often have competitive civil service systems that are modeled on the national system, in varying degrees.