Mailchimp Single Opt-In

I need to make Mailchimp single opt-in on my s2member registration form. How do I do this?

In the ni-mcapi.inc.php I found the function below but I want a way to change this without directly editing s2member files.

function listSubscribe($id, $email_address, $merge_vars=NULL, $email_type='html', $double_optin=true, $update_existing=false, $replace_interests=true, $send_welcome=false) {
    $params = array();
    $params["id"] = $id;
    $params["email_address"] = $email_address;
    $params["merge_vars"] = $merge_vars;
    $params["email_type"] = $email_type;
    $params["double_optin"] = $double_optin;
    $params["update_existing"] = $update_existing;
    $params["replace_interests"] = $replace_interests;
    $params["send_welcome"] = $send_welcome;
    return $this->callServer("listSubscribe", $params);
}
 

Hi Nicola,

If you’re referring to the double opt-in requirement (where MailChimp sends the customer a signup confirmation email where they need to click a link to confirm their subscription), you can disable that using a filter. Please see this thread for more info.