The .US top-level domain (usTLD) was established in 1985 as the official country code top-level domain (ccTLD) for the United States. It is administered by NeuStar.
The expanded second-level .US domain launched on April 24, 2002, enabling companies, nonprofits, government entities and individuals to establish unique, memorable American addresses online.
U.S. NEXUS REQUIREMENT
To be in compliance with the U.S. Nexus Requirement, all registrants for the .US domain must be either:
A natural person (i) who is a citizen or permanent resident of the United States of America or any of its possessions or territories, or (ii) whose primary place of domicile is in the United States of America or any of its possessions, or
An entity or organization that is (i) incorporated within one of the fifty (50) U.S. states, the District of Columbia, or any of the United States possessions or territories or (ii) organized or otherwise constituted under the laws of a state of the United States of America, the District of Columbia or any of its possessions or territories, or
An entity or organization (including a federal, state, or local government of the United States, or a political subdivision thereof) that has a bona fide presence in the United States.
This U.S. Nexus Requirement is intended to ensure that only those individuals or organizations that have a substantive connection to the United States are permitted to register for .US domain names.
.biz（NeuLevel：A joint venture of NeuStar, Inc. and Australia-based Melbourne IT, Ltd.）
.us＝＞ US 23.9-45 for two years
.biz ＝＞US 45-63 for two years
.us＝＞ "BEST OF .US" CONTEST, “Hear why 68 million Americans prefer .US!”
.biz＝＞ “BIZ Promote” （search engines and directories）