If I'm writing a formal letter (for example, applying for a job), I will use one of the following endings: ----------Most formal----------- I remain, sir/madam, yours faithfully, Lewis. Please do not hesitate to contact me. Yours faithfully, Lewis. I eagerly await your reply. Yours faithfully, Lewis. Yours faithfully, Lewis. Many thanks, Lewis. -----------Least formal----------- In personal letters, it goes like this: ----------Most affectionate------- With all my love, Lewis. (only for use with family/significant others) With love, Lewis. (only for use with family/significant others) Love, Lewis. Best wishes, Lewis. Yours sincerely, Lewis. Yours, Lewis. Regards, Lewis. Thanks, Lewis. ----------Least affectionate--------

Best wishes All the best Sincerely

Best wishes is the most natural, informal ending to a letter from your list.