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Our friends at MarketingSherpa recently released their annual Email Marketing Benchmark Report, which always contains interesting tidbits on how folks like us go about building their subscriber lists and more. One tidbit was that only 39% of email senders use confirmed opt-in lists, which lead us to ponder on why single vs. confirmed is so polarizing.

But first, a little background on single opt-in and confirmed (or double) opt-in. Let’s say you have a form on your site that’s pointing to a subscribe list. If it’s single opt-in, it will accept new subscribers immediately after the form is submitted. However, confirmed opt-in lists include an interim step, which usually involves an email being sent to the subscriber’s email address first. Once a link in the email is clicked (thus confirming that the email address is valid), the subscriber is added.

Weighing up the pros and cons

There are fairly straightforward advantages and disadvantages to each approach. While single opt-in is less complicated than confirmed for both email senders and subscribers, it does open up subscriber lists to collecting invalid email addresses – either as a result of honest mistakes, or spambots. On one end of the scale, these invalid email addresses can be a mild annoyance, but on the other, they can be an expensive problem, impacting your campaign metrics, delivery rates and bottom line.

That said, the commitment that goes into confirming twice-over can deter would-be subscribers, even if it is a good measure of future engagement. But then, if a would-be subscriber never receives the confirmation email – say, because it gets stuck in spam – then they won’t get a chance to receive future campaigns.

Is there a ‘correct’ approach?

Given these two sides, it’s easy to see why folks may be either unsure, or passionate about whether their approach is the correct one. From our perspective, they’re both valid – although we see the value in going confirmed, especially in regards to boosting engagement rates and keeping subscriber lists clean. So at this point, we’d like to turn the discussion over to you – do you use single, or confirmed opt-in for your lists? Why? Let us know in the comments below.

  • Jason Rodriguez

    I use single opt-in for all of my personal project lists. I can get away with it since the audience is highly targeted and there is little risk of bad emails really being a problem. If you know about one of my projects and sign up for a list, chances are it’s not a mistake.

    At work, our clients use confirmed list since they are MUCH larger and the higher numbers mean that more bad email addresses are likely to get through.

    Good job outlining the tradeoffs that need to be weighed, Ros.

  • Robby Joe

    I too use single opt-in for all my all project as it prevent from spamming

  • Jeffrey Barke

    @Robby Joe

    I’m confused by your comment. It seems to me that double opt-in is the way to go if you’re concerned about spamming.

  • Carl Michael

    This is a case of quantity vs quality with a bit of UX thrown in.

    A double opt-in approach produces a more robust list at the expense of list size. I’m not aware of any research into the matter, but I’d estimate that well under half of those filing out a double opt-in email subscription actually confirm their subscription. People are just too busy, can’t be bothered etc…

    Now what that does mean though is that you get an email list of people who are willing to go that extra step to get your content. These people are going to engage with you more, and should be more loyal.

    The approach that I take in my job as a Digital Marketer is to use a single opt-in with a ‘confirm email’ box. I try to point out what the subscriber can expect to receive and how often. I also ensure that the privacy policy, and terms are close at hand.

  • Monika

    At German and Austria you have to use double opt in because of the privace police.

  • Oli

    My view on this is simple. I use you guys for all emails and until I can resend double optins confirmation when they get missed, I’ll stick to single optins :)

  • Centro Professionale Europeo “

    In Italy you can use single opt-in. But we prefer double opt-in not only to prevent from spamming, not only to have a real measure of engagement,
    but also for ethical reasons. Is it weird?

  • Michael Graham

    We are in a constant battle with this question. Its clear that you get more loyal and qualified engagement from double opt in. And yes, you do loose a good deal of potential confirmations because users either don’t see it (junk mail) or delete it before confirming. We see typically about a 20% confirmation rate.

    What I think hurts the double opt in process somewhat is the lack of ability to customize the confirmation email itself. Its really difficult to encourage user engagement from a text only based email.

    With those two things said, what would be ideal would be:
    1. Be able to resend the confirmation at least once
    2. Be able to custom build what the confirmation email looks like just like auto-responders or campaigns

  • B X

    The reason I chose Campaign Monitor, and not one of your competitors, is because they require double opt-in and you don’t. So please don’t change! I prefer single opt-in because it is easier on the user and will therefore give us a bigger email list.

  • Sean Wood

    We use a double opt-in. We have found over time that emailing thousands of people who don’t respond is not as effective as emailing a smaller number that want to engage with you. And half the battle in creating an effective engagement is to have Campaign Monitor connected to your CRM so you close the loop and have the bounces, opt-outs and campaign results feed right back into your CRM system.
    Using this approach we have built a significantly more engaged mail list.

  • Steven P

    Isn’t the question not “what do other businesses do” but “what do customers/readers want”? Has anyone asked them?

  • Søren Sprogø

    Single opt-in, always. And it stems from the belief that everytime a user has to go through a step more in a process, there’s a great chance he’ll abandon it.

    But one thing that puzzles me: Shouldn’t it be pretty easy for you guys (at CampaignMonitor) to get some hard figures on the effectiveness of double opt-in? Isn’t it pretty easy to track that whenever you send out a opt-in mail, how many of those users actually end up on a list?

    This could be a hugely important figure in persuading me to do double opt-ins in the future. Or not.

  • Fred Schlomka

    We discovered that we were losing too many valuable subscribers via double opt-in. So we went to single opt-in. Love it.

  • Peter

    As was already mentioned: German courts will require doube opt-in and recipients may be awarded damages if you send emails after a single opt-in. The argument is that anyone can subscribe others via a form and thus the actual recipient is not really opting in.

  • Paul Mycroft

    With the RSS-to-Email feature activated, you need to go to double opt-in so you don’t pay to send to spambots and to “Donna Gabriel” and her friend “Ivan Ballard”.

    If you could add a way to resend the confirmation email or change the FROM address so it doesn’t get caught in junk boxes, that would be a nice addition.

  • Mark Kennerley

    I work as at an eCommerce company and we use both single and double opt in.

    We have integrated the CM API into our checkout/confirmation process and have this as a single opt it, as these customers are committed and we see this email as their genuine email.

    We also have a sign up form as part of the general site and we have this one as a double opt in, as people can use other peoples email addresses.

  • Irene

    ” But then, if a would-be subscriber never receives the confirmation email – say, because it gets stuck in spam – then they won’t get a chance to receive future campaigns.”

    If single or double opt-in letter stuck in spam, all the rest emails will go to spam folder as well.

    We use double opt-in email but the confirmation rate is too low, less than 15%. I’m not quite sure that it’s Ok.

  • Nguyen

    The double opt-in is better because it helps you identify real leads instead of fake emails and people who are not so interested in your product. However, I get about 50% of subscribers who don’t confirm their email, even when I write a note next to the form to tell them check their spam folder and confirm. Anyone knows how to improve this rate?

  • Ratko Ivanović

    Søren Sprogø – love the suggestion, I think the effectiveness would be great.

    I think it should be on a situation basis. As Mark stated, if you have a form deep in your page and you can say with certainty that a user will use theirs, it’s single opt-in. Aside from the spam bots, although you can prevent them easily, you know you have a clean list.

    I’ve been wrapping my head around this for some time, and don’t think I have a good grasp.

    But what I can say is if you go double opt-in, you need to sort out the UX side of it. And make sure you make it as easy as possible for the users to confirm them as leads.

This blog provides general information and discussion about email marketing and related subjects. The content provided in this blog ("Content”), should not be construed as and is not intended to constitute financial, legal or tax advice. You should seek the advice of professionals prior to acting upon any information contained in the Content. All Content is provided strictly “as is” and we make no warranty or representation of any kind regarding the Content.
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