Last updated 01/26/2026
Before adding Bread & Butter’s Subscription Booster, make sure you have added the initialization script tag.
The Subscription Booster popup dialog will pop up after a specified number of seconds, prompting the user to sign in to subscribe to your newsletter, contest, or special offer. You can then use our integrations to put the user right into your mailing list, via Mailchimp, Zapier, HubSpot, etc.
Bread & Butter remembers who has signed up, and won’t prompt them again. The Subscription Booster will be hidden for 24 hours for users who dismiss it without signing in.

This guide explains how to add the Subscription Booster to any page on your site, and how to configure the content you want it to display, including header image.
On the page you want the Subscription Booster to appear, add the following JavaScript:
BreadButter.ui.addNewsletterWidget({
header_text: 'HEADER_TEXT',
main_text: 'BODY_TEXT',
success_header: 'SUCCESS_HEADER',
success_text: 'SUCCESS_TEXT',
custom_event_code: 'CUSTOM_EVENT_CODE',
delay_seconds: 5,
optin_dismiss_time: 1440,
image_default: 32, //from 1 ... 36
background_color: "#FFFFFF",
font_color: "#000000",
button_color: "#50aff5",
button_font_color: "#FFFFFF",
});
All of the available parameters are explained below. Feel free to configure them to meet your specific requirements, or remove them altogether to use the default text and configuration.
Use the text fields to let your visitors know what you want them to sign up for, and the benefits they get for signing up.
Replace CUSTOM_EVENT_CODE with the user event code that you want to trigger when a user signs up. Head to Automations, then the User Events tab to create a new custom event.
Note: A custom event code is required to complete the Subscription Booster setup.
For the left side image, you can choose from a set of 36 default images, your own custom image, or no image.
image_source: "URL_HERE", and enter your own image URL. Recommended size: 450 x 600 pixels.image_type: "none",.For colors, you can set the backgound color, text color, button color, and button text color for the sign in options section. You only need to adjust these if the default colors don't mesh with your existing site color palette. Enter the hex code for the colors you want.
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