How do laws treat mixed-content emails (e.g., receipt + promo)?

Most regulatory frameworks apply a "primary purpose" test to determine how mixed-content emails should be classified. Under CAN-SPAM, if the primary purpose of a message is commercial, it must comply with commercial email requirements regardless of any transactional content included. The FTC evaluates primary purpose by examining what a recipient would reasonably conclude the email is about-considering the subject line, the placement and proportion of commercial versus transactional content, and overall visual emphasis.

CAN-SPAM's specific guidance states that if the subject line would lead a recipient to think the message is commercial, or if the commercial content appears first or is given greater prominence than transactional content, the message will be treated as commercial. For truly mixed messages where commercial content is present but secondary, the message may retain transactional classification if the transactional purpose remains clearly primary. The ureceipt is obviously the main event, with promotional content being a minor addition.

Under GDPR and ePrivacy, the analysis is similar but focuses on legal basis rather than message classification. The transactional portion can be sent under contractual necessity, but any promotional content requires a separate legal basis (consent or legitimate interest). This means you need valid grounds for both components. Simply including promotional content in a transactional email doesn't automatically grant permission for the promotion. You ustill need consent for marketing content even if it's riding alongside legitimate transactional information. Mixing promotional content into transactional emails is permitted within limits, but crossing the line transforms the entire message into a marketing email requiring full compliance.