You can try the following things : You could try using forms/surveys and also you could try out sending periodic newsletters about the latest happenings related

You can try the following things : You could try using forms/surveys and also you could try out sending periodic newsletters about the latest happenings related to your business line. Keep a catchy subject line. Use bulleted points instead of paragraphs in the email. Keep a personal touch in the content like use their first or last name in the greeting, sign off with your name instead of the website team May be you could provide a really good reason why people should reply to you than just saying plainly the feedback - make them feel they are reason for your growth.