I personally use the US when speaking about the country generally, the States when talking to someone overseas (about coming over, comparatively), and rarely, or never the USA .
However, I think generally, most people use the US in conversation.
I think the only time I hear people use the USA is when they say it emphatically and patriotically.
ell.stackexchange.com/users/6650/CocoPop
In US, the word most commonly spoken out of three is "US".
"USA" is more formal and official.
While, based on my own experience, "States" is hardly used by natives.
As a general rule, spoken language uses the smallest available options.
ell.stackexchange.com/users/4126/JuliandotNut
As far as I know, "US" can be used as an adjective while the others can't (though I'm not sure why) -- "US cities" is OK but
"USA cities" or "States cities" sound weird.
That might be one reason for its frequency.
ell.stackexchange.com/users/681/Max
Some of the trouble comes from being a federation of states, not a single country.
"The States" refers to the collection of states, "The US" refers to the states that are united, or, more loosely, to the union of States.
The problem is that there's very, very, very many nations made up of multiple states.
Even Belgium is made up out of 3 parts that could very well be called states.
"
The USA" is therefore the only unambiguous way to refer to "The United States of America", in fact it might better be "The United States of North America".
Ultimately, the USA have no name for there union!
Except maybe just "America", after the continent it is the biggest nation in.
It would also retrofit the use of "Americans", which probably used to refer to people that lived on the continent, but now refers to citizens of "The United States of (North) America".
Ultimately it doesn't matter.
The US, The States, the USA, it all refers to the same thing in people's heads.
Just use the word your audience expects you to, that'll work best.
ell.stackexchange.com/users/9297/Lodewijk
well, here in Brazil it is comon to refer to USA as "the States", although we say a "brazilianized" version of it : "
os estates".
We use it to refer to America, since it it easer to say than "US" or "USA" and we also try to say "os estates" with an American accent to make it sound more "American".
Also Brazilians do not refer themselves as Americans, neither to Canadians.
Americans refers exclisively to people from the USA.
Canadians are Canadians and Brazilians are Brazilians.
ell.stackexchange.com/users/9307/Stephane Duchemin
USA - United States of America.
US - United StatesThe States -
well, self-explanatory
I'm from England
and I have never heard anyone English refer to it as the states, though I've watched American sitcoms where a character might say it.
We don't really say the US either, we prefer saying America or USA, moreso America than anything else (despite theire being two seperate contintnets which have America within their name).
I think it's just a preference thing, but like I said the English like saying America or USA Note:
we use 'America' for North America.
ell.stackexchange.com/users/9292/SomeAmbigiousUserName
When I travel oversea, I always answer that I am from States, and people understand.
When my friends come back from travel oversea, I ask either "when were you back to States?"
or "When were you back to US?"I rarely use USA in conversation, I use it in formal paper.
I was taught that way.
ell.stackexchange.com/users/8649/user138473
Are the any differences in formality or context between "the USA", "the US" and "the States"?   I've tried NGram and it seems that "the US" is by far the most common expression and "the States" is the least common (would you sound like you are from the 19th century if you used it?). Of course, the search doesn't include spoken language.   Finally, in a conversation, would you say "the US" or "the United States?
Differences between "the USA", "the US" and "the States"
ell.stackexchange.com
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ell.stackexchange.com/questions/30621
ell.stackexchange.com/users/3948/jinawee
 In the US, the word most common out of three in conversation is "US". People mau use the US  when speaking about the country generally, and the States  when talking to someone about coming over from overseas.  "USA" is more formal and official. "US" is also used as an adjective while the others are not. The US is most commonly used.
The US is most commonly used.