CAN-SPAM

CAN-SPAM does not require consent before a first commercial email, which is why cold email is lawful in the United States. It does set rules for every such message, and the FTC's compliance guide is explicit that the law makes no exception for business-to-business email. The From, To and routing information must be accurate; the subject line must not mislead; the message must identify itself as an advertisement where that applies; and it must include your valid physical postal address.

Each message must also tell recipients how to stop further email from you, and you must honour an opt-out within 10 business days, and not sell or transfer the address afterwards. You remain responsible when another company sends on your behalf. Other countries have stricter rules, so CAN-SPAM is the floor for US recipients, not a standard for everyone.

Sources: FTC, CAN-SPAM Act: a compliance guide for business (ftc.gov, checked oct 22, 2026).