· 5 min read
Unsubscribes in cold email: the rules and the right thing to do
What the mailbox providers and the main laws expect when someone asks you to stop, and how to make sure they never hear from you again.
When someone asks you to stop, stop — everywhere, immediately, for good. It's what the law expects, what mailbox providers check for, and what keeps a "no thanks" from turning into a spam complaint.
This article is general information, not legal advice. The rules depend on where you and your recipients are; ask a lawyer about your situation.
What the rules expect
United States — CAN-SPAM. Commercial email must include a clear way to opt out, your physical postal address, and honest subject lines and headers. Opt-outs must be honoured within 10 business days, and you can't charge for or complicate the process.
European Union and UK — GDPR and ePrivacy rules. Emailing business contacts usually relies on legitimate interest: the message must be relevant to the person's role, you must say who you are and how you got their details, and you must stop as soon as they object. Rules for emailing individuals are stricter, and some countries require consent even for business addresses.
Canada — CASL. Generally requires consent before sending commercial email, with narrow exceptions. It's the strictest of the three.
What the mailbox providers expect
Since 2024, Google and Yahoo require bulk senders to support one-click
unsubscribe (the List-Unsubscribe header that shows an "Unsubscribe" link
next to the sender's name) and to keep spam complaints low. An easy, visible
way out is far better for you than the "Report spam" button.
Doing it properly
- Make it easy. A plain line works: "Not relevant? Reply 'stop' and I won't email again." Add an unsubscribe link as well.
- Stop everywhere. An opt-out from one campaign must stop every campaign, including ones you launch next month.
- Treat replies as opt-outs too. "Please remove me" in a reply counts.
- Keep a suppression list. Store the addresses (and, if they ask, whole domains) you must never email again, and check every new import against it.
- Never re-import them. The most common way people get emailed after opting out is a fresh CSV that includes them again.
How Outsquid handles it
Campaign emails carry a one-click unsubscribe header. An unsubscribe — or a hard bounce, or a blacklist entry you add — stops the prospect in every campaign at once and keeps them out of future ones. You can blacklist a single address or an entire domain.