E-mail subject abbreviations

This is a list of commonly and uncommonly used abbreviations which are used in the subject of an English email header.

These prefixes are usually automatically inserted by the email client.

These words are inserted in the middle of or at the end of the subject, usually by the author.

The following prefixes are often used in software development:

This is a list of abbreviations which are less commonly used in the subject of an English email header:

The email client will typically check for an existing "Re:" when deciding whether or not to add one in front of the subject. However, clients may use different abbreviations if the computer is set up for a non-English language, e.g. "AW:" for German, and this can mean that a conversation between two participants can build up convoluted subject lines like "Re: AW: Re: AW: ..".

To avoid this, email clients may have an option to force the use of the standard English abbreviations even when all other features are presented in another language, or to recognize other forms.

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