How do I address my bishop? “Hello, Father,” while correct, doesn’t convey the full respect due his office. Is he “Your Excellency” or “Your Eminence”? Are there more and less formal forms of correct address and when is each used?
In spoken conversation, you would call your bishop “Bishop (last name)” or “Your Excellency.” In opening a letter, you would put “Dear Bishop (last name)” or “Your Excellency” (“Dear” is not used in front of “Your [title]”). In addressing an envelope you would put on the first line “The Most Rev. (full name)” and on the second line “Bishop of (diocese).”
Archbishops follow the same protocol as bishops. Cardinals are addressed as “Cardinal (last name)” or “Your Eminence.” Letters to cardinals open “Dear Cardinal (last name)” or “Your Eminence.” In addressing the envelope the first line would read “(first name) Cardinal (last name)” or “Cardinal (full name)”; the second line would read “Archbishop (or Bishop) of (archdiocese or diocese).”