Editing Pro (section)

=== What is a single opt-in? ===
A single opt-in means that email or SMS contacts will not be asked to confirm their subscription to your list. Once they submit your form, subscribers are added as “Active” contacts to your list right away.

==== Pros of a single opt-in: ====
* Allows email or SMS contacts to join your list so they can start receiving messages right away.
* One less step a contact needs to take before they receive messages from you.

==== Cons of a single opt-in: ====
* For email contacts:
** Contacts may end up on your list who did not want to receive messages from you, and they may mark your email as spam. This can hurt your deliverability.
** Spam contacts are added to your list as active contacts.
* For SMS contacts: 
** Contacts may end up on your list who did not want to receive messages from you, and they may STOP reply to your SMS. This will unsubscribe the contact from your SMS marketing list.

To enable single opt-in for your form, view this help document.