Q: I’m trying to figure out the proper way to abbreviate United States, given that I’ve seen it in different ways. Which is correct/proper: US, U.S., USA, or U.S.A.?
A: Some dictionaries and style guides prefer the dotted versions while others recommend the dotless ones, but both are acceptable. In general, dotted abbreviations are falling out of favor, so I’d go for the dotless ones.
Oops! I’ve just noticed that I’ve been using dots with “US” on The Grammarphobia Blog. From now on, no more dots.
As for “US” vs. “USA,” they’re equally acceptable as nouns, though US is preferred as an adjective (“US products,” “US policy,” “the US economy”).
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