SourceTag

Installation

Install SourceTag on Squarespace

Add SourceTag’s tracking script to your Squarespace site through the built-in Code Injection settings. No third-party apps or extensions needed.

Step 1: Copy your script tag

In your SourceTag dashboard, go to your site’s detail page and copy the script tag. It looks like:

<script src="https://cdn.sourcetag.io/scripts/YOUR_SITE_ID/st.js" async></script>

[IMAGE: Screenshot of the SourceTag dashboard showing the script tag on the site detail page]

Step 2: Open Code Injection

  1. In your Squarespace dashboard, go to Settings
  2. Click Advanced
  3. Click Code Injection

[IMAGE: Screenshot of the Squarespace Settings menu with Advanced > Code Injection highlighted]

Step 3: Paste the script tag

  1. In the Header section, paste the script tag you copied from SourceTag
  2. Click Save

[IMAGE: Screenshot of the Squarespace Code Injection page with the SourceTag script tag pasted in the Header field]

The script will now load on every page of your Squarespace site.

Step 4: Publish

If your site is already live, the change takes effect straight away. If you’re working on an unpublished version, publish your site to make the script active.

Step 5: Test

Visit your live site with UTM parameters in the URL:

https://yoursite.com/?utm_source=test&utm_medium=cpc&utm_campaign=squarespace-test

Open your browser’s developer tools (F12 or Cmd+Option+I on Mac) and check:

  1. View page source or the Elements panel to confirm the script tag is in the <head>
  2. Application > Cookies to confirm a _sourcetag cookie has been created
  3. Submit a form on your site. Check the form notification in Squarespace. The submission should include hidden fields with attribution data like st_fc_channel and st_lc_channel.

[IMAGE: Screenshot of browser developer tools showing the _sourcetag cookie]

Notes

  • The script works with Squarespace’s native form blocks. Hidden fields are added automatically when a form is detected on the page.
  • If you’re embedding a third-party form (Typeform, HubSpot, etc.) on a Squarespace page, the script will detect those too via MutationObserver.
  • Browser cookies are limited to 7 days on Squarespace. There’s no server-side cookie workaround available for Squarespace sites. See Safari Cookies for more detail.
  • Code Injection is available on Squarespace Business and Commerce plans. If you’re on a Personal plan, you’ll need to upgrade to access this feature.