Take note

A list-unsubscribe header for commercial mail is required for compliance with deliverability standards enforced by many mailbox providers (such as Google, Yahoo!, or Microsoft 365). Transactional emails, such as payment receipts, membership or helpdesk login emails, etc., do not include the list-unsubscribe header.

Marketing emails sent from Kartra automatically contain a list-unsubscribe header. When supported, mailbox providers use the list-unsubscribe header to display an “Unsubscribe” link at the top of the message window.

In the recipient’s inbox, the link looks something like this (example from Gmail):

One-click unsubscribe link in Gmail

Note: The exact format of the link varies depending on the mailbox provider and may not be displayed at all if the provider does not support it.

The purpose of the unsubscribe link is to give recipients the option to unsubscribe from your list with a single click, saving them from having to search your content for the link or go to your website to complete the action.

In many cases, the one-click unsubscribe link can help reduce spam complaints, by giving recipients a convenient way to unsubscribe instead of clicking the spam button in their inbox.


Understanding list-unsubscribe

The one-click unsubscription link you see at the top of some email messages is generated by a line of code in the message called a “list-unsubscribe header.”

Kartra automatically adds a list-unsubscribe line to the header code of all commercial emails sent from your account. This lets the recipient’s mailbox provider display the unsubscribe link in their message interface and specifies the action that will take place when the link is clicked.

Transactional emails do not contain a list-unsubscribe header.


List-unsubscribe actions in Kartra

When someone clicks the one-click unsubscribe link in a message from Kartra, the resulting action depends on where the message came from in the sender's account and how it was configured.

Emails (single-send)

Best practice: Always use “subscribed to list” as the primary recipient criteria for an email to give your contacts the option to opt-out. You can add additional conditions to refine the recipient group further using the AND/OR fields.

The exact action triggered by clicking the one-click unsubscribe link depends on how the recipient group is defined in the email setup. In general, the one-click unsubscribe for a single-send email removes the contact from a list.

Recipient conditions and unsubscribe action:

  • If recipient condition is subscribed to any list: Clicking “unsubscribe” removes the contact from all lists.
  • If recipient condition is subscribed to one or more specific lists: Clicking “unsubscribe” removes the contact from only the lists specified by the recipient criteria.
  • If recipients are defined by any non-list criteria (such as all contacts with a specific tag, subscribed to a sequence, or with access to a membership): Clicking “unsubscribe” removes the contact from ALL lists they are subscribed to.

Important: If the contact is not subscribed to any list, clicking unsubscribe flags the lead as “Do not contact” and they are blocked for future mailing.

Sequence emails

  • Clicking “unsubscribe” removes the contact from the sequence the message came from.

Webinar or Calendar reminders

  • Clicking “unsubscribe” stops any new reminder messages for the specific webinar or calendar that generated the email.

Pro tip

Clicking the one-click unsubscribe link does not directly impact a contact's tags or any other factors without subscribe/unsubscribe characteristics.

However, any automations configured to run based on a list unsubscription action WILL complete when a contact is unsubscribed via the one-click link.