When you’re finishing a letter or e-mail, how should you capitalise the final phrase (or ‘complimentary close’, to give it its official name)? Should you give all the words a capital letter, just the first one, or none at all? This is a point that even native speakers are often uncertain about!
The answer is: you capitalise only the first one. This applies to both business and personal correspondence, and to both UK and US English. The following are therefore all written correctly:
With best wishes
Of course, if there is only one word in the close, then that gets a capital:
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