Post-nominal letters, also called post-nominal initials, post-nominal titles or designatory letters, are letters placed after the name of a person to indicate that the individual holds a position, educational degree, accreditation, office, or honour. An individual may use several different sets of post-nominal letters. The order in which these are listed after a name is based on the order of precedence and category of the order. Post-nominal letters are one of the main types of name suffix.

post-nominal letters

according to wikipedia.

A post-nominal is the short form of qualification after your name. An example might be PhD or CPA. In the US they often begin with the letter "C" meaning certified.

I believe that the answer to your question is post-nominal letters.