You can include any Unicode character in the subject line or body of an email or SMS
Take care when pasting content into the subject or body of the email that special characters look correct. If it looks correct, it should arrive intact, although some recipients may not be able to decode special characters correctly. Examples of special characters are accented characters e.g. ä é, emdash (—), arrows: (→) etc.
You can also include emoticons by copying and pasting them. Here’s a good site to find them: https://getemoji.com/