Postnominal letters

Post-nominal letters, also called post-nominal initials, post-nominal titles or designatory letters, are letters placed after a person's name to indicate that that individual holds a position, academic degree, accreditation, office, military decoration, or honour, or is a member of a religious institute or fraternity. An individual may use several different sets of post-nominal letters, but in some contexts it may be customary to limit the number of sets to one or just a few. The order in which post-nominals are listed after a name is based on rules of precedence and what is appropriate for a given situation. Post-nominal letters are one of the main types of name suffix. In contrast, pre-nominal letters precede the name rather than following it.

For a list of types of post-nominal letters see the following link:

The order in which post-nominal letters are listed after a person's name is dictated by standard practice, which may vary by region and context.

In the United States, standard protocol is to list post-nominal letters in the following order:

Active duty services personnel do not use any post-nominals other than, if applicable, Staff Corps affiliation (Navy only) followed by a comma and then their branch of service. Names are bracketed by the appropriate pre-nominal and post-nominal, e.g. LCDR John Q. Public, MC, USN.

In the United Kingdom various sources have issued guidance on the ordering of styles and titles for British citizens, including the Ministry of Justice and Debrett's; these are generally in close agreement, with the exception of the position of MP, etc., in the listing:

In addition, British citizens who have received honours from Commonwealth countries with permission from the Queen are usually allowed to use the postnominals of that honour.

The Oxford University Style Guide and the University of Nottingham Style Guide give the alternative ordering:

This differs from the civil ordering in that it omits appointments except for QC, includes diplomas and certificates in addition to degrees, merges medical qualifications, fellowships of learned societies, royal academicians, and membership of professional bodies into a single item, and omits membership of the armed forces.

Loughborough University gives a very similar ordering, but with "Appointments (e.g MP, QC)" replacing item 3 (QC) and "Higher Education awards (in ascending order, commencing with undergraduate)" replacing items 4–6 (Degrees, Diplomas and Certificates). This restores the Appointments section from the civil list omitted by Oxford and Nottingham, although the other differences remain.

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