IntroducedFebruary 15, 1985; 34 years ago (1985-02-15)
TLD typeCountry code top-level domain
SponsorNational Telecommunications and Information Administration
Intended useEntities connected with the United States United States of America
Actual useLow to medium popularity in the United States due to gTLDs
Registered domains1,715,757 (March 2016)[1]
Registration restrictionsU.S. nexus requirement can be enforced by challenge but seldom is
Structure2nd-level registrations allowed; originally only 3rd- or 4th-level registrations in a complex hierarchy
DocumentsRFC 1480; USDoC agreements with Neustar
Dispute policiesusTLD Dispute Resolution Policy (usDRP)

.us is the Internet country code top-level domain (ccTLD) for the United States of America. It was established in 1985. Registrants of .us domains must be American citizens, residents, or organizations, or a foreign entity with a presence in the United States of America. Most registrants in the United States of America have registered for .com, .net, .org and other gTLDs, instead of .us, which has primarily been used by state and local governments, even though private entities may also register .us domains.[citation needed]


On February 15, 1985, .us was created as the Internet's first ccTLD.[2] Its original administrator was Jon Postel of the Information Sciences Institute (ISI) at the University of Southern California (USC). He administered .us under a subcontract that the ISI and USC had from SRI International (which held the .us and the gTLD contract with the United States Department of Defense) and later Network Solutions (which held the .us and the gTLD contract with the National Science Foundation).

Postel and his colleague Ann Westine Cooper[3] codified the .us ccTLD's policies in December 1992 as RFC 1386[4] and revised them the following June in RFC 1480. Registrants could only register third-level domains or higher in a geographic and organizational hierarchy. From June 1993 to June 1997, Postel delegated the vast majority of the geographic subdomains under .us to various public and private entities. .us registrants could register with the delegated manager for the specific zone they wished to register in, but not directly with the .us administrator. In July 1997, Postel instituted a "50/500 rule" that limited each delegated manager to 500 localities maximum, 50 in a given state.[5]

In June 1998, Postel raised the possibility of covering IANA operating costs by charging locality name registrars, who would pass the costs along to individual registrants. In September 1998, the United States Postal Service proposed funding the operations in order to assume control of .us, as part of a plan to diversify away from postage revenue.[6] On October 1, 1998, the NSF transferred oversight of the .us domain to the National Telecommunications and Information Administration (NTIA) of the United States Department of Commerce.[7] Postel died that month, leaving his domain administration responsibilities with ISI. In December 2000, these responsibilities were transferred to Network Solutions, which had recently been acquired by Verisign.[5][8][9]

On October 26, 2001, Neustar was awarded the contract to administer .us. On April 24, 2002, second-level domains under .us became available for registration. One of the first .us domain hacks, icio.us, was registered on May 3, 2002, for the creation of the subdomain del.icio.us.[10][11] A moratorium was placed on additional delegations of locality-based namespaces, and Neustar became the default delegate for undelegated localities.[12] Neustar's contract was renewed by the National Telecommunications and Information Administration (NTIA) in 2007 and most recently in 2014.[5][13]

On March 31st, 2019, The .US registry [14] made it clear that under its Acceptable Use Policy it would not allow the sale of opioids through the .US top level domain.