What is a double opt-in and why should we use it?


If you’re planning a dinner party, you’ll want to know how many people are attending, right? With email strategy, double opt-ins are like the RSVPs of your newsletter: They ask potential subscribers to confirm their sign-up before being added to your list. This adds guardrails to protect your list from unengaged subscribers, misspelled email addresses, and bots or spam. This means you’re less likely to be ghosted, have miscommunications, or pay for a total distribution list that is far higher than the number of people actually receiving your emails.

How Double Opt-in Works

If you’re using a double opt-in, when a subscriber fills out a form to sign up for your email list, they’re not immediately added to that list. Your email marketing tool will automatically send them an email asking them to confirm their subscription before they are added.
In that purgatory period before your subscribers confirm, you can’t email them or access their information. If you choose to move forward with using a double opt-in (most email marketing tools have an option), we recommend adding copy to your confirmation page or success message reminding people to check their inbox to confirm their subscription. An example from Whole Whale client Lung Cancer Foundation of America:


Why We Recommend a Double Opt-in

Yes, if you add guardrails to slow down the subscription process, this can lower your acquisition rate and limit the growth of your email list. But while double opt-ins will reduce the number of people that are actually added to your list, they will also increase the quality of emails being added. By only adding emails that are functional and belong to people interested enough in your organization to double opt-in, the likelihood of them engaging with your newsletter increases. This means higher open and click-through rates, which means more people actually reading what you send, taking action, and driving impact (and donations).
Adding a double opt-in will also reduce your bounce rates and unsubscribe rates, which, when they get too high, can impact your deliverability rate. If bounce rate gets too high, this can send your emails into the spam folder, and even possibly flag your emails — meaning they wouldn’t get sent at all.
Finally, if you operate in the European Union, double opt-ins function as added confirmation that a subscriber is giving you their data and permission to message them, which satisfies the conditions of GDPR.

What about CAPTCHA?

Good question! CAPTCHA is a program that creates and grades tests that humans can pass and robots cannot. CAPTCHA is designed to protect against spam from entering your site or your subscriber database and will reduce the likelihood of robots email addresses from getting on your list.
If this has been a problem, or if your database needs to be extra secure, we recommend adding CAPTCHA to your forms. Double opt-in can help to remove some robots from your list, but it’s largely used to actively get consent and increase the quality of lists.

Does this really work?

Whole Whale client Lung Cancer Foundation of America was battling a bounce rate of over 10% back in 2017 — which is well above the nonprofit average of 0.4% as reported by Mailchimp. After adding a double opt-in to their user flow process, their bounce rate dropped dramatically to 0.66% and continues to decrease with time.
Have more email questions? We have a full resource here for nonprofit email marketing.

“What are email users doing on my site?” asked every nonprofit ever. With Lighthouse by Whole Whale, we’ve created a virtual handshake between your email marketing provider and your Google Analytics to better understand the online activities of high-value email subscribers. Get more information and sign up for a demo at getlighthouse.io.