[From Cambridge English]

Have got and have mean the same. Have got is more informal.
I’ve got a terrible pain in my back.
I have a terrible pain in my back. (more formal)
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Question: What about in American English? In American English, 'have got' is more informal? Is 'have' formal?

4 answers

Yes, that's also true of American English.
It's about the same, although in American English the use of "got" is often considered repetitious. If "I have" and "I have got" mean the same thing, then why use the extra word?

=)
In speaking, I often use "got" when it's not necessary.
Same here!! =)