What does an email footer legally have to contain?

What systeme.io puts down there for you

Two things, both in Settings under Emails.

• An unsubscribe link. A tick box labelled Display "Unsubscribe from campaign" link switches it on. The words on the link are yours to write, and the wording can be set separately for each language.
• Footer text. A free text box underneath. Whatever goes in it appears at the bottom of your emails.

The footer text is held per domain rather than once for the account. The dropdown above the box lists your account address and every verified sender address, so a business running two brands can give each of them different wording, different links and different contact details.

The badge you cannot take off for free

Emails carry a "Sent with systeme.io" line at the bottom by default, and that line is an affiliate link promoting systeme.io.

A second tick box in the same Emails settings controls it, the one about displaying an affiliate link at the end of every email sent. Clearing that box removes the badge, and it needs a paid subscription: Startup, Webinar or Unlimited. Accounts on the free plan cannot take it off.

Why the unsubscribe link is worth more than compliance

systeme.io treats a visible unsubscribe link as protection for the sender rather than a concession to the reader.

Somebody who does not want your email has three ways out: unsubscribe, stop opening, or press the spam button. The first costs one contact. The second quietly drags your open rate down. The third damages your sending reputation and, done often enough, can get you blacklisted by email providers.

Of those three, the cheapest one is the one worth making visible.

The legal part is not systeme.io's to answer

The help centre publishes no legal checklist. It does name two things. Unsubscribe links are mandatory on a marketing platform. And its deliverability guidance asks you to sign your emails, putting your name, brand name and information in the footer, along with the company name and a link to your website if you trade as one. It adds that being identifiable this way is necessary for some destinations, German servers among them.

Its compliance guidance goes further on consent than on footers. Consent has to be voluntary and active, the box has to be unticked by default, the wording has to say what the person will receive, and a record of it is worth keeping: the date, the context, and the exact wording they agreed to. That record is what answers a complaint or an audit later.

Whether your footer also needs a postal address, a company number or anything else is set by the law where you trade and where your readers live, and it differs between countries. That is a question for your own jurisdiction or an adviser, not for a help article about a tick box.