Make a Double Opt-in Form with Ninja Forms!

You can craft a clean, professional double opt-in form quickly and easily with Ninja Forms. With email marketing and newsletter mailing lists, the quality of your leads is critical to your success. How do you filter out great leads from matches that never should have been made in the first place? It starts with making sure every last name on your list is an intentional addition that’s eager to hear from you. Learn to build an attentive audience with a double opt-in form right now!

Why a Double Opt-in Form?

Your brand reputation is on the line any time you’re accessing a reader’s inbox. Similar to a credit score, a Sender Score is kept for IPs and domains that grades the trustworthiness of a an email sender’s IP.[1]

Every email you send that is marked as spam counts against your Sender Score. It’s mission critical that you minimize the number of times your emails get marked as spam. There are a variety of different steps you can take to accomplish that, and a double-opt in to ensure all recipients really do want to hear from you is one of the most crucial. The number of subscribers you have on your list is not as important as the quality of those subscribers!

What Exactly Is a Double Opt-in Form?

A double opt-in, sometimes called a confirmed opt-in, is simply a two step process in which your reader will opt in to your newsletter once and then be required to confirm that they do indeed want to be on your mailing list before they are officially added.

Won’t this deter some readers from subscribing? Yes, but for good reason. Maintaining a reputable Sender Score is critical to your marketing efforts, and ensuring that each and every one of your subscribers are quality leads that want to hear from you is integral to that goal.

What Do I Need?

  1. Ninja Forms
  2. One of our Ninja Forms newsletter extensions + a free account with that service:

That’s it!

How Do I Do This?

Install and activate Ninja Forms and the newsletter service extension of your choice. The activation and setup documentation for each of our extensions can be found on the extension’s product page on That process will involve creating a free account with your chosen service.

With several of our extensions such as MailChimp and AWeber, that’s all you’ll have to do! Double Opt-in is enabled by default with those services. For ones that don’t, it doesn’t take more than a few clicks to set it up. Let’s look at Constant Contact as an example.

1) Enable the Constant Contact extension in Forms>Settings>Constant Contact in your WordPress Dashboard.

double opt-in form step 1: constant contact activation

2) Sync your sign-up form by opening the form via Forms, clicking the Settings tab of the form, expanding the Display option, enabling Constant Contact, and choosing the list you want it to add to.

double opt-in form step 2: linking constant contact to your subscription form

3) Sign in to your Constant Contact account and in the upper right hand corner, under My Account, click My Settings. Now under the Manage My Settings screen, toggle Confirmed Opt-in to ON.

double opt-in form step 3: enabling double (confirmed) opt-in in constant contact

That’s all there is to it. With a double opt-in you not only safeguard the reputation of your brand online, but you ensure that your mailing list is built on quality leads. For more on how you can protect your email marketing reputation be sure to check out our post on how to avoid spam filters, and if you’re looking for a primer on spam filters and common causes for email to be flagged as spam, we have you covered there too. We wish you the best of luck in all your email marketing efforts, and if you have questions don’t hesitate to post them below!