Well, you use thank you either if it's a formal letter (and in any part of it) or not while you normally use best regards at the end of a formal letter
Using both 'Thank You' and 'Regards' in the conclusion and closure of a letter would be unusual. 'Thank You' and 'Regards' are both used in less formal letters, with 'Regards' being slightly more formal, and somewhat dated.
An ending (complementary close) for a formal letter might include : Yours, Yours truly, Yours sincerely, Sincerely, Sincerely yours, Thank you
An ending (complementary close) for a formal letter might include : Yours, Yours truly, Yours sincerely, Sincerely, Sincerely yours, Thank you
You thank whoever you are sending the letter to the on the right side of the paper you write Yours faithfully, your signature, your name.
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Thank you is formal than thanks
Writing a proper formal thank you letter is very easy. You can just write out a letter and let the person know how you feel and that you appreciate all they did. An outline or template can be found online at the site CareerOneStop.
A formal letter should begin with one of the following: Dear Madam, Dear Sir, To whom it may concern. When you end the letter please add one of the following: Thank you, (insert name here), Best regards, (insert name here).
A simple "thank you" note or email should be sufficient to express you appreciation for recognition. A formal letter is not necessary.
They both mean the same thing. However, "thanks" is less formal than "thank you".
Mercy (informal)Khaylee mamnoon (Thank you very much) (formal)