What is double opt-in?

Double opt-in is a confirmation process used in email and SMS marketing to make sure subscribers chose to receive your messages. After someone signs up for your list through your website, social media, or another marketing channel, they receive a confirmation email or SMS with a link. When they click on the link, their subscription to your mailing list is confirmed.

How to implement double opt-in

To implement a double opt-in process for your email or SMS marketing efforts, follow these steps:

  1. Choose a reliable marketing automation platform: Make sure your platform allows you to toggle between double opt-in and single opt-in so you have a choice—but sets double opt-in as the default so you’re also always compliant. Your marketing automation platform should make SMS double opt-in with keywords particularly easy, as carriers often require it for certain types of messages. 
  2. Craft a compelling sign-up form: Design a simple sign-up form that can collect an email address or phone number, which will trigger the double opt-in message to confirm subscription. In regions where GDPR applies, an opt-in checkbox is also required.   
  3. Write your double opt-in message: Within your marketing automation platform, create your confirmation email. These messages include brand indicators that make it clear the email is coming from your business, a call to action (CTA) button to confirm the subscription, text that explains they subscribed to your list, and contact information for your business.
  4. Specify a confirmation keyword: For SMS, specify a keyword that a recipient can reply with to confirm their subscription (usually “YES”). You’ll need to include this in your double opt-in message.

5 benefits of double opt-in

Using double opt-in benefits your business by:

  1. Engaged subscribers: Double opt-in means only engaged subscribers make it to your list, improving open rates, click rates, and conversions.
  2. Ensuring compliance with regulations: Double opt-in helps you comply with regulations like GDPR and CAN-SPAM
  3. Reduced chances of spam complaints and bounces: Double opt-in verifies email address and phone number accuracy, which helps to make sure more of your messages are making it to inboxes.
  4. Reducing fake and malicious sign-ups: With a single opt-in, anyone can enter any email address or phone number. Double opt-in verifies the legitimacy of each sign-up.
  5. Building trust and credibility: A double opt-in process shows subscribers that you value their privacy and only send them relevant information. This builds trust and credibility with your target market, leading to long-term brand loyalty.

A marketing automation platform like Klaviyo streamlines the double opt-in process for your email and SMS marketing efforts. With Klaviyo, you can create customisable sign-up forms with clear opt-in checkboxes, trigger automated confirmation messages, and follow up with personalised welcome emails or SMS.

Sign up for Klaviyo to simplify double opt-in, build stronger subscriber relationships, and get the most out of your email and SMS marketing initiatives.

Additional resources