gov is one of the original top-level domains created in 1984[4] (the other five being com, org, edu, mil, and arpa).

In February 2011, the GSA selected Verisign to manage the registry services, replacing Native Technologies, Inc.[6] Responsibility for the TLD was transferred to the Cybersecurity and Infrastructure Security Agency (CISA) under the DOTGOV Online Trust in Government Act of 2020,[7] part of the Consolidated Appropriations Act, 2021.

In January 2023, CISA selected Cloudflare to replace Verisign in providing registry services.

[12] Federal Executive branch policy requires the use of .gov for civilian agencies,[13] but some U.S. government-related websites use non-.gov domain names, including the United States Postal Service (e.g., usps.com) and various recruiting websites for armed services (e.g., goarmy.com).

The United States Department of Defense and its subsidiary organizations typically use the .mil sTLD instead of .gov.

U.S.-based government organizations and publicly controlled entities are eligible to obtain a .gov domain.

The signer of the letter differs by entity type, but it is typically an agency's head, chief information officer (CIO), or highest-ranking or elected official.