How to add a popup to October CMS

By Mert Özeren, Customer Success Specialist at Popupsmart · Updated September 24, 2026

To add a popup to October CMS, paste Popupsmart's embed code just before the closing </body> tag in your theme layout, then build, target and publish popups from the Popupsmart dashboard. October CMS has no popup builder of its own, and Popupsmart needs no Marketplace plugin, so nothing new runs on your server.

Add a popup to October CMS

Setup at a glance

Runs on: October CMS
Where the code goes: CMS → Layouts → before </body>
Add-on: No plugin needed

Before you start

You need three things, and a developer isn't one of them:

Access to your October CMS backend with permission to edit the theme's layouts. If you haven't bookmarked it, add /backend to your site's address.
A free Popupsmart account. The free plan covers one website and one live popup, so you can finish this guide without paying.
The address your visitors use for the site, which Popupsmart verifies after the install.

An October CMS popup from Popupsmart needs one embed code in the layout your pages share, added once. After that you build, change and publish popups in Popupsmart without opening October CMS again.

Step 1: Copy your embed code

Popupsmart dashboard with the Embed Code section highlighted

Click Copy to clipboard. The code is one line, <script src="https://cdn.popupsmart.com/bundle.js" data-id="…" async defer></script>, and the data-id belongs to your account.

Popupsmart popup with the option to copy to clipboard

Step 2: Paste the code into your October CMS layout

In the October CMS backend, open CMS, then Layouts, and open the layout your pages use. Themes name it differently: default.htm is common, and the theme in the screenshot calls it master.htm. On the Markup tab, paste the embed code just before the closing </body> tag, then click Save.

October CMS dashboard with the option to paste embed code in master.html

According to October CMS's documentation on layouts, a layout holds everything that repeats on every page, and each page names the layout it uses. If your theme has more than one layout, paste the code into each of them, or into a footer partial that all of them include (the screenshot's layout includes site/footer). When I set this up with a customer, I put the code in that shared footer partial rather than in each layout, so there is one copy to maintain.

Step 3: Add and verify your website

Back in Popupsmart, hover over the profile icon at the bottom left and click Websites.

Click + New Website.

Popupsmart dashboard with the option to add a new website

Enter your site's address and click Save.

Popupsmart dashboard with the option to enter the website URL and click Save

If the site shows as Unverified, click Unverified, then Verify website, and go back to the dashboard and click Refresh. The guide to verifying your website covers the other cases.

Click + New Campaign. Name the campaign, choose your October CMS website and click Next.

Popupsmart dashboard with the option to create a new campaign

Pick a template, then change its copy, colours and form fields to match your site, and save.

Popupsmart dashboard with the option to save and publish the October CMS popup

Click Publish. Then open your site in a private window and load a page that uses the layout you edited. The popup appears when its trigger fires.

No. October CMS has no popup builder for your visitors; an October CMS popup comes from a Marketplace plugin or from code in your theme. As of September 2026, a search for "popup" on the October CMS Marketplace returns one plugin, Small Messages by Jan Vince, a free plugin that shows notices and announcements in a Bootstrap modal or as plain HTML.

	Small Messages (October CMS plugin)	Popupsmart
Where it runs	Inside your October CMS install, as a component you add to a layout, page or partial	Any website that accepts the embed code; paid plans cover several sites (3 on Basic, unlimited on Expert)
When it opens	When the page loads; no other trigger is documented	Exit intent, scroll depth or time on page
Pages	Selected URLs only, with dates from and to; a cookie keeps a hidden message away	URL and device rules on each campaign
Where the leads go	Not documented; the plugin shows messages, not forms	The help center lists 19 destinations, including Klaviyo, HubSpot and Mailchimp
A/B testing	Not documented	From the Advanced plan
Updates	Version 1.2.7 added October CMS 3 support in December 2023	Hosted by Popupsmart; nothing to update in October CMS
Price	Free	Free plan: one website, one live popup, 5,000 pageviews a month; paid plans from $39 a month

Small Messages is a good fit for a notice, such as a holiday closure or a new opening time, on a site your team already maintains: it's free and stays inside October CMS. Popupsmart earns its install when the popup has to collect emails and send them to your email tool, open on exit intent or scroll, or run the same way on sites that aren't on October CMS.

An October CMS popup is limited to some pages by a targeting rule in Popupsmart, not by moving the embed code. The code stays in the shared layout and only loads Popupsmart; each campaign's URL targeting rule, such as "the URL contains /blog", decides where it shows. You can move a popup to other pages later without editing the theme again.

Pages are half of the rule, and timing is the other half. In Popupsmart's 2026 benchmark, popups that wait before appearing convert 0.83% against 0.61% for popups shown the instant the page loads (median campaign), a lean rather than a proven gap, and exit intent shows no statistically reliable advantage. When a popup fires is worth deciding on purpose, so choose the trigger in the same step as the pages.

October CMS runs agency sites, company sites and online shops, so start from the job the page has:

Newsletter signups on blog and content pages: the email popup guide.
Lead forms on service pages: the callback popup recipe.
A last offer for visitors about to leave: the exit-intent popup recipe.
A launch or event, with a countdown and a signup: the countdown popup recipe.

October CMS popup leads go from Popupsmart to the email tool you already use, so they don't sit in October CMS. Popupsmart can send every email address and phone number a popup collects to that tool; you connect it in the campaign's Integration section. The Klaviyo popup guide and the SendGrid popup guide walk through a connection; the help center lists 19 destinations, and a webhook, Zapier or Make covers a tool that isn't one of them.

A Popupsmart popup doesn't hold up your October CMS pages: the embed code loads asynchronously (async defer), so the browser finishes building your page before it fetches Popupsmart. Nothing is added to the server side of October CMS: no plugin runs when a page is rendered.

When an October CMS popup doesn't appear, work down this list; the first cause is specific to October CMS.

The page uses a different layout. Open the page under CMS → Pages, check which layout it names, and add the embed code to that layout too.
The website isn't verified. A campaign runs only on a verified website; see Step 3.
The address doesn't match. www.example.com and example.com are different sites to a browser. Add the address your visitors actually use.
A cache is serving the old layout. If your site uses a caching plugin or a CDN, clear its cache after saving the layout.
A Content Security Policy blocks the script. If your server sends a CSP header, add Popupsmart's script domain, cdn.popupsmart.com, to it.
The trigger hasn't fired yet. An exit-intent or scroll trigger waits for the visitor to leave or scroll; test in a private window and behave like a visitor.

💬

From the support queue: When a popup shows on part of an October CMS site and not the rest, what I check first is the layout. Each page names its layout, and a page built on a layout without the code loads no popup while every other page works. My advice is to open that page under CMS → Pages, read the layout it uses, and make sure the layout, or a partial it includes, carries the code.

Yes. Popupsmart's free plan is permanent, not a trial: one website, one live popup and 5,000 pageviews a month, with Popupsmart branding. It is enough to install the code and run your first popup on an October CMS site.

The Popupsmart pricing page compares it with the paid plans.

No. You paste one line of code into your theme layout once. Everything else, from the design to the targeting, happens in Popupsmart's visual editor.

Do I need an October CMS plugin for popups?

No. Popupsmart runs from the embed code in your layout, so there is nothing to install from the October CMS Marketplace and nothing to update when October CMS updates.

A free plugin such as Small Messages still suits a simple notice; the section on October CMS's built-in options compares the two.

Yes. Every October CMS layout is an HTML template with a closing body tag, and the embed code goes just before it, whatever the theme.

The October CMS side is one paste into a layout; the rest is building the popup. Among people who published a campaign in the 90 days to 16 September 2026, the median time from signup to the first published campaign was 32.5 minutes, and 287 of 332 published within a day, according to Popupsmart's own product data. That figure covers every platform, not October CMS alone.

How to add a popup to October CMS

Before you start