>Found a relevant discussion >http://stackoverflow.com/questions/1592291/what-is-the-email-subject-length-limit > >and also > >http://www.networkworld.com/newsletters/2010/060710web1.html > >A subtle but crucial issue in the use of email and one that marketers often neglect is how long a subject line can and should be. The answer to "can be" is defined in RFC 2822 which states that "There are two limits that this standard places on the number of characters in a [email message] line. Each line of characters MUST be no more than 998 characters, and SHOULD be no more than 78 characters, excluding the CRLF." > > >Now the "should be" part: The 78 character limitation has been ignored by many online services who only allow much shorter subject lines. The result of this is that subject text will be truncated to whatever arbitrary maximum length they permit. >
