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Single Opt-in vs. Double Opt-in: The Court of Public Opinion


The case has been made for single opt-in and the case has been made for double opt-in. This contest is clearly one of great public interest, judging by the number of people who have testified by commenting and by the reactions of people on Twitter and elsewhere.

These comments deserve consideration and the public’s opinion will be heard, but first let’s again be clear on who the two parties are in this dispute:

  • Single opt-in (SOI) is a subscription process where a new email address is added to your mailing list without requiring the owner of that email address to confirm definitively that they knowingly and willingly opted in
  • Double opt-in (DOI), also known as confirmed opt-in (COI), is a subscription process where a new email address is only added to your mailing address after the email address owner clicks a confirmation link in a subscription activation or opt-in confirmation request email that’s sent to them after they opt in via a form or checkbox

With those formalities out of the way, let the voice of the people be heard!

In a Worldwide Poll

Marketers are closely divided on which is the better opt-in method. Before making our cases for SOI and DOI, slightly more marketers were in favor of single opt-in.


It’s worth noting that 60% of our respondents were from the US, and the remaining from elsewhere around the world. Among US respondents, 55% said SOI was better, versus 45% saying DOI was better. In the rest of the world, the gap was narrower, but the result was the same, with 51% saying SOI was better and 49% saying DOI was.

Curious to see if our arguments were persuasive and to better gauge the reactions of those most interested in permission practices, we ran the exact same poll between May 26 and June 8 but only solicited responses from people who read either our SOI post or DOI post. Among the 264 visitors who responded, 45.1% were for single opt-in and 54.9% were for double opt-in—essentially a reversal of the larger, more scientific poll.

Both of these results demonstrate just how divided the email marketing community is on this issue.

Witness Testimonies

Polls are great, but what are individuals actually saying about the issue? Here are a few select testimonies from those who commented on the SOI and DOI posts or on Twitter:

Roanne Parker's comment

John Oelze's comment

Thomas Bacon's comment

Scott Christley's comment

There is passion on both sides of the debate, plus some great advice. However, a few comments also reveal some confusion.

For instance, some people think that single opt-in is illegal in Germany, Canada, or in other countries. It’s not illegal anywhere in the world that we’re aware of. Even in Germany, where privacy and security laws are incredibly strong and the courts have stated that single opt-in isn’t sufficient proof of permission, most companies don’t use double opt-in, according to research by Teradata.

It’s Not Too Late to Have Your Voice Heard

Want to be a witness for either single opt-in or double opt-in? Want to share your experiences with or opinions on SOI or DOI?

Just comment below or on The Case for SOI or The Case for DOI blog posts, where plenty of people have already shared their views.

Before You Make You Decision…

Hear both sides of this debate and the final verdict:

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