Out of all the customers that receive your invitation email for your survey, how many actually fill it in? The first bottle neck where you can lose out on most of your potential responses, is getting customers to open your email. And that all evolves around subject lines.

With these 20 example subject lines you'll learn about the psychological principles that increase the likelihood of people opening your email.

This ebook you will learn:

    The 6 fundamental principles to create subject lines that beg to be clicked on.
    How one underlying aspect should rule all your attempts at optimizing subject lines.
    And more...


Which of these subject lines will you test first?