How to Connect OptinMonster with a Custom HubSpot Form

In addition to our native HubSpot integration, OptinMonster makes it easy for you to use a custom HubSpot form in your campaigns. You can use a custom HubSpot form to add additional fields to your form or other custom functionality.

In this article, you’ll learn how to add a custom HubSpot form to your OptinMonster campaign.

Before You Start

Here are some things to know before you begin:

  • This article assumes you’ve already created a campaign in your account to add your custom HubSpot form to.
  • Custom HubSpot forms don’t automatically track conversions when they are submitted in OptinMonster. It’s important to update your custom HubSpot form code as instructed in this guide.
  • You may need to add custom CSS to style your form as desired. Custom HubSpot forms do not automatically inherit the campaign’s template styling.
  • When adding a custom HubSpot form, the form actions cannot be set in the Design area of the campaign builder. It is also not possible to display the Success View of your campaign. You’ll need to specify a redirect URL or success message through your Email Service Provider Account settings when you create the form.

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Edit Form Code

Before your custom HubSpot form can work in OptinMonster, you’ll need to make a few modifications to the embed code you’re provided.

The embed code you receive will look something like the following:

You’ll need to add:
  • An empty div with the class .custom-hubspot-form-{{id}} below the HubSpot form code as a target for the form to populate inside of.
  • The target: 'html div#om-{{id}} .custom-hubspot-form-{{id}}' attribute
  • The onFormSubmit function to track conversions.
  • The onFormSubmit function to show the Success view on conversion or close the campaign automatically.

The above additions will cause your form code to look similar to the following:

Add Custom HubSpot Form

You can add extra fields to your form or include other custom functionality using a custom HubSpot form in OptinMonster.

To add a custom HubSpot form to your OptinMonster campaign, follow these steps:

  1. Log into your HubSpot account and create the form you wish to add to your OptinMonster campaign.
  2. Follow the instructions provided in the previous section of this guide to edit the form embed code HubSpot provided you with.
  3. Next, follow our Custom HTML integration guide to add the form code to your campaign.
  4. When you’re finished, click Save.


Why do I add an empty div to my form code?

HubSpot’s form code will completely overwrite any existing content in the container it is targeted to. This can cause problems if you’re creating a Yes/No campaign or have entered any other code or text in the Custom HTML field. By targeting the form to an empty div both of these problems are completely avoided.

What does the onFormSubmit code do?

The onFormSubmit addition allows your campaign to track conversions and set a cookie when the form is successfully submitted. Without this addition, no conversions will be tracked or cookies set on form submission.

How do I track subscriber events?

You’ll need to refer to HubSpot’s documentation on using their Events Javascript API to track subscriber events.

Email Automations

To send emails automatically to new leads you’ll want to configure email automations within your HubSpot account.

The following guides from HubSpot may be helpful to get started: