Are single quotes legal in the name part of an email address?

robotrobot picture robotrobot · Jan 27, 2011 · Viewed 31.5k times · Source

For example:

jon.o'[email protected] ?

Answer

aioobe picture aioobe · Jan 27, 2011

Yes, jon.o'[email protected] is a valid email address according to RFC 5322.

From the Email address article at wikipedia (Syntax section):

The local-part of the email address may use any of these ASCII characters:

  • Uppercase and lowercase English letters (a–z, A–Z)
  • Digits 0 to 9
  • Characters ! # $ % & ' * + - / = ? ^ _ ` { | } ~
  • Character . (dot, period, full stop) provided that it is not the first or last character, and provided also that it does not appear two or more times consecutively (e.g. [email protected]).

(The syntax is formally defined in RFC 5322 section 3.4.1 and RFC 5321.)