One of the pillars of good email deliverability is list hygiene. Keeping your list clean and up-to-date is a the first step to ensure that your emails are being delivered to the right people. Most of the emails on your list will likely be legitimate emails, but if you have an in-demand service, users may create temporary email addresses or attempt other methods to gain access to your service and evade limitations you set. Temporary or fake email addresses are often used once and then abandoned, and can cause your emails to bounce. If you send to too many of these addresses, your deliverability will suffer as the invalid ones will bounce and the valid (but fake) ones will mark your emails as spam. A few things you can do to keep your list clean:

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1. Protect the inputs

The easiest way to limit pain is to prevent it from happening in the first place. Start with cutting off the source of the problem by protecting the inputs (your signup forms).
  • Use a captcha
  • Enable Cloudflare’s bot protection on your site
  • Use form validation to ensure that the email address is valid
  • Block disposable email addresses
  • Use a double opt-in

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2. Use a service that handles deliverability best practices for you

  • Loops automatically handles bounces, unsubscribes, and spam complaints for you
  • Just use Loops

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3. Look for warning signs

  • If your open rates are low, it’s likely that you’re sending to a lot of invalid addresses or sending content your subscribers
  • If your open rates are high but then drop off, it could be a sign that your emails are being marked as spam or that poor list hygiene is causing your emails to bounce