Let me correct the forum.

I am a native speaker from the USA.

In the United States, you normally write: "Best Regards,"

In the UK, you normally write: "Best regards,"

That is the difference. Americans write the word Regards with capital letter to underscore the sincerity of the wish. It is like a birthday card with the writing "Happy Birthday," instead of "Happy birthday." The latter would not look very sincere, even though it is grammatically correct.

For those puritans out there, UK English is the original variant. For those practical people out there, US English is the de-facto global standard, since the USA controls most of the technology and social platforms, tools and services of the Internet.

The first word is typically the only one capitalized in a personal closing; however, hard-and-fast rules do not govern this area. I learned "Best Regards" in middle school.

Americans are the one who usually capitalize the second word. I have never seen an English person (my manager or colleagues, for instance) or co-workers who learned English as a second language (e.g. in Germany) do it.

I am a US native speaker living in Europe for the past 14 years. I note all the little differences in the language and punctuation. Thanks.

@Miguel373: hm -- us is an English native speaker currently living in the US.

At least as far as the US is concerned, #9 is absolutely incorrect.