Last week we worked on split testing to increase sales conversions. This week we will talk about a new email header that is slowly being adopted by software vendors and ISP to make it easier for people to unsubscribe from a mailing list. This weekend project is good for those that have developed their own script to send out a newsletter.

A general email header looks something like this…

From: josh@domain.ca
Subject: Test Email
Date: August 23, 2008 3:13:02 PM PDT
To: jasmine@domain.ca

The new header field looks like this…

List-Unsubscribe: <mailto:unsubscribe@domain.ca>, http://domain.ca/unsubscribe/?email=jasmin@domain.ca

This new header field allows for both an email and link to unsubscribe.

If you were using this in a test php email your script would look like this…

<?php
$to      = ‘nobody@example.com’;
$subject = ‘the subject’;
$message = ‘hello’;
$headers = ‘From: webmaster@example.com’ . “\r\n” .
    ‘Reply-To: webmaster@example.com’ . “\r\n” .
    ‘List-Unsubscribe: <mailto:unsubscribe@example.com>’;

mail($to, $subject, $message, $headers);
?>

If you have written your own mailer script using I suggest you begin investigating this project now.

If you get stuck let me know in the comments.