Note: Information in this article applies to both Classic and Lightning Experience.
RFC, or "Request for Comments," refers to a set of technical standards that define the rules for email formatting and transmission. RFC standards govern the structure of an email address and its headers, ensuring compatibility between different email systems across the internet.
Salesforce makes every attempt to conform to the latest RFC standards related to email. There are some areas where Salesforce diverges from these specifications, though in the majority of use cases this does not impact customers' ability to send email to specific addresses.
The following sections describe the supported email address formatting standards in Salesforce, including known areas of RFC compliance gaps.
Supported Email Format Standards
..) are allowed in the middle and at the end of the local part of an email address (e.g., a..a@test.jp and a..@test.jp) but not at the beginning (e.g., .a@test.jp). This diverges from RFC standards but was specifically requested by customers in Japan due to local email provider practices.john.doe@(comment)example.com and john.doe@example.com are equivalent.The RFC specification contains gray areas — including features marked as obsolete but kept in the specification. Salesforce is likely out of full compliance with:
Both of these are less commonly used features, and Salesforce Support receives very few issues related to them.
If a specific email address format causes unexpected behavior in your Salesforce org, document the exact address format and contact Salesforce Support with the following information:
Note: Salesforce does not provide regex or sample code that covers all email address validation rules.
Additional information:
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