Double opt-in Emails vs Single opt-in Emails: Which Option is Best for Business

Ask ten different email marketers about which is better for building responsive email lists: single opt-in or double opt-in.  Half will say single opt-in, the other half will say double.  So, are half the email marketers wrong when it comes to this issue?  And if so, which half are right?

Well, in some ways, both sides are right.  Although, as you’ll see, when using EmailOversight’s Email Validation and Hygiene, one side is “more” right than the other.

Let’s start with the “process.”

Single opt-in subscribers saw an offer that interested them.  They then entered their email data on a form fill or other input area on your website or lead-gen page.  Once they clicked submit, they were put on your list.

On the backend, their email address, and other data such as IP address and time/day of opt-in are saved in case they’re needed in the future (for fighting spam complaints, etc.).

These subscribers agreed to be on your list in 1 quick and simple step.

Now, maybe you send them a welcome letter, or a series of follow-ups.  Or maybe you begin pitching products immediately, maybe you don’t.  Perhaps you only send content for the first few weeks…

After a single click, they’re your subscribers and how and when you market to them is up to you.

But the first thing you won’t be sending them is this:  a solicitation to verify their address and intent to opt-in, yet again… the double opt-in.

You see, single opt-in subscribers are added to your list as soon as they agree to it.  They’re ready to begin receiving your messages right away.  And you’re ready to begin sending to them right away.

But if you’re using the double-opt in email method, things are a lot different.

Double-opt in email names are only added to your list after the prospective subscriber has gone through a multitude of time-consuming steps.  Steps that can cause you to lose their attention, and their email address.

Just like the single-opt in email address, these prospects found an offer that interested them (your offer) and entered their email data on a form or lead-gen page.  But unlike the single opt in, they now need to receive a confirmation email, find the confirmation email, open the confirmation email and click to confirm.

That’s three additional steps THEY have to take before they’re finally part of your list… Additional steps forced upon them before they’re in your funnel generating revenue.

Now, it’s understandable why many email marketers prefer the double-opt in method.  Nobody wants addresses added to their email lists that can cause hard bounces, are spam traps or are simply invalid emails.  Email addresses like these will not generate a single dollar in revenue, and only cause problems down the road.

Problems like lower deliverability rates, lower open rates, higher bounce rates and ultimately, without constant hygiene, all your messages, even ones to good subscribers, could end up in the spam folder.

So, the double-opt in method is used to ensure the initial email data input was legitimate, not a made-up address, and they’re not spam traps.

Double opt-in marketers force more clicks on their prospects before a single sale is ever made.  All in the name of hygiene and protecting the assets down the road.


You can actually build a clean, responsive email list with the single click opt-in method using EmailOversight.

Our email validation and hygiene system can remove all the harmful and bad addresses from your lists.  And we can do it regardless of whether you use single or double opt-in.  But this goes beyond maintaining hygiene…

Did you know you can verify email addresses without the extra steps involved with double opt-ins?

By using our API on your forms and websites, you can validate and verify single opt-in email addresses live, just as they’re entering your list.  Ensuring they’re legitimate and ready to send.

It’s the best of both worlds.  You can operate a list that has the initial hygiene levels of double opt-in, but without the extra user steps involved.  Without the dreaded “extra clicks.”

With our API, every incoming email address is checked for validity, whether or not it’s a spam trap or if the address comes from a known “complainer”…. a real email address belonging to a person who has a habit of hitting the spam button.  A subscriber you don’t want.   And all this happens in near real-time!

So, by using EmailOversight’s API, your single opt-in email addresses can be just as clean and responsive as double opt-in addresses… without all the extra work needed from the prospect, or you!

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