Dotdigital blog

The power of double opt-in (DOI) for email deliverability

Discover the power of double opt-in (DOI) in email marketing and how it can boost your email deliverability. Uncover its benefits, including improved list quality, sender reputation protection, and defense against malicious attacks.
A marketer learning about double opt-in (DOI) for their email marketing campaigns.

Are your emails ending up in the spam folder? Despite crafting compelling content, your messages might be missing their mark. The culprit? A lack of double opt-in (DOI) in your email marketing strategy.

This blog dives into how DOI can be your secret weapon for boosting email deliverability. We’ll explore how it improves list quality, protects your sender reputation, and safeguards against malicious attacks. By the end, you’ll understand why DOI is a critical step for ensuring your emails reach the inboxes that matter.

Understanding double opt-in (DOI)

Double opt-in, also called confirmed opt-in, is a verification process that involves two steps. Subscribers must confirm their email address and consent to receive communications by responding to a confirmation email. This extra step ensures that the provided email address belongs to the intended individual and is valid, thereby safeguarding both the sender and the recipient.

The benefits of DOI for deliverability

  1. Enhanced list quality: DOI is the only way to be 100% certain that a) the email address exists, b) the owner of the email address is the one subscribing, and c) the email address owner definitely wants marketing emails from your brand.
  2. Protection against reputation damage: DOI filters out invalid or potentially harmful addresses, protecting against hard bounces and spam traps that could damage sender reputation and impact inbox placement.
  3. Defense against malicious attacks: DOI acts as a robust defense against abusive practices, such as bot scripts adding email addresses without consent. Additionally, implementing supplementary security measures like CAPTCHA further fortifies the defense against unauthorized additions to mailing lists, safeguarding both sender reputation and recipient experience.

Risks of neglecting DOI

  1. Lower quality addresses: Neglecting DOI may result in more addresses being added to lists but at the cost of lower quality. Without DOI, there’s a higher chance of including disinterested or even fake addresses, diminishing the engagement metrics of your campaigns.
  2. Damage to sender reputation: Sending to large lists with low engagement, especially without DOI, can damage sender reputation. This not only reduces inbox placement but also jeopardizes the overall deliverability of your emails.
  3. Vulnerability to attacks: Neglecting DOI opens the door to various attacks, including list bombing, whereby malicious actors target email addresses with excessive emails making them unusable. Without DOI, businesses are more susceptible to malicious activities aimed at exploiting loopholes in subscription forms.

The DOI takeaway

Email marketing success depends on many factors, but one of the most crucial is deliverability. To ensure that your emails reach their intended recipients, it’s essential to follow best practices, such as using a double opt-in process. DOI helps to improve the quality of your email list, safeguard your sender reputation, and protect against malicious attacks. Before launching your next email campaign, make sure to implement DOI to increase your chances of success and protect your sender reputation.

Back to top

Recommended reading