US and U.S. Wikipedia:Manual of Style

mos:us
mos:notusa

us commonly used abbreviation united states, although u.s. – periods , without space – remains common in north american publications, including in news journalism. multiple american style guides, including chicago manual of style (since 2010), deprecate u.s. , recommend .

for commonality reasons, use default when abbreviating, retain u.s. in american or canadian english articles in established, unless there reason change it. because use of periods abbreviations , acronyms should consistent within given article, use in article other country abbreviations, , avoid constructions u.s. , uk. in longer abbreviations incorporate country s initials (usn, usaf), never use periods. when united states mentioned 1 or more other countries in same sentence, (or u.s.) may informal, @ first mention or noun instead of adjective (france , united states, not france , us). not use spaced u. s. or archaic u.s. of a., except when quoting. not use u.s.a. or usa except in quotation, part of proper name (team usa), or in technical/formal uses (e.g., iso 3166-1 alpha-3, fifa, , ioc country codes).

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