CAN-SPAM
CAN-SPAM is the US law governing commercial email. It permits cold outreach without prior consent, provided the headers are accurate, the message is identifiable, a physical address is included and opt-outs are honoured within ten business days.
It is an opt-out regime rather than an opt-in one, which makes US cold email structurally easier than its European equivalent. There is no requirement to have a prior relationship.
The obligations that do exist are strict and mechanical: no forged sender information, no deceptive subject lines, a valid postal address in the message, and a working unsubscribe. Penalties are assessed per message, so a compliance failure across a large send is not a small number.
Canada's CASL is a different regime entirely and materially stricter — it requires consent, express or implied, before the first message. Sending to a Canadian list on the assumption that CAN-SPAM rules apply is a common and expensive mistake.
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