Double Opt-In: the double opt-in process is the recommended approach used in email marketing. Typically, the double opt-in method requires the subscriber to submit their email address for the first opt-in, then click a link in an email automatically sent by the list owner. This second opt-in confirms the user's interest in receiving an email newsletter or being part of an email list, greatly reducing spam complaints, pranks, and more, while increasing engagement levels.

Doubt Opt-In email marketing is often the best approach for both companies and their users. While social media and content marketing have become two of the most encouraged forms of online marketing, email lists and campaigns can still be extremely effective: research shows that 44% of email recipients made at least one related purchase over the course of a year due to the newsletters and promotions they received. Moreover, email marketing can be used as a method to spread content to users who are more likely to be interested in and promote this content. As a result, double opt-in methods can be an important part of a company's content marketing strategy, ensuring that content is being delivered to engaged customers, promoting brand loyalty and encouraging a healthy reputation.