Build a Single Opt-In Online Form


by 123FormBuilder

Opt-in forms are the quickest way to grow your email subscriber list. You can create online forms that are primarily meant to get new contacts (we’ll deal with them in a future article) or online forms and surveys that are designed for other purposes, but can bring collateral benefits. By using the opt-in feature instead of automatically adding email addresses to your mailing list, you reduce bounce rate significantly, for subscribers express their wish to be added to the list and are less likely to unsubscribe.

There are two types of opt-in lists: single opt-in and double opt-in. With single opt-in forms, subscribers are asked one time only if they would like to be added to your email list. Double opt-in’s require a double confirmation – after potential new subscribers have expressed their desire to join your mailing list, they are asked once again, via email, for confirmation. Single opt-in forms and double opt-in forms have their pros and cons.

Single opt-in lists grow faster, but they may gather people that do not really want to be on those lists. Double opt-in lists need more time to grow and may be of better quality. However, we believe that, both in the short and in the long run, single opt-in lists are more effective because: a) they do require subscribers’ opt-in decision and b) anybody can unsubscribe at any time.

123FormBuilder web forms can easily be linked to newsletter and mailing lists. To create a single opt-in online form, you need to: 1. Build a form. 2. Add an opt-in checkbox to your form. 3. Integrate it with a third party application: SalesForce, MailChimp, VerticalResponse or iContact (to which you will send new email addresses). We’ll discuss these steps below.

1. To create a single opt-in online form you have, first and foremost, to build your web form. Build a short contact form, an order form, an online survey, an event registration form or whatever it is that you need. The opt-in feature can be added to any type of online form.

2. To add the opt-in checkbox to your form, open the form editor and drag a checkbox field to your main view. Place it at the bottom of your form. Focus on its Edit panel. Delete Choice 2 and Choice 3 from the Available Choices box. Replace Choice 1 with the text that you want form users to see; for instance: Add me to your mailing list. Delete the field label and there you go – the opt-in checkbox has been created. Now let’s add some functionality to it.

3. Go to your SettingsApplications section and connect to your preferred third party application. If necessary, read our documentation on how to integrate SalesForce, MailChimp, VerticalResponse and iContact with your form. Select, in the dropdown list labeled Send, the option Only if choice is checked: (opt-in message). Press Save and that’s it!

From now on, each time a form user ticks the opt-in checkbox and send the form, a new email address will be added to your mailing list. Log in or sign up for a 123FormBuilder account and create your single opt-in online form!


  1. Pingback: Single Opt-In Form Newsletter Subscription | Smashing Forms

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