How to add custom code to a Squarespace site

• A Core, Plus or Advanced plan. Squarespace says some legacy billing plans include code injection too.
• The script from your tool, as a complete <script> tag
• A login that can open the site’s Code Injection panel

1. Open the Code Injection panelOn version 7.1, open the Pages panel, click Custom Code at the bottom, then Code Injection. On version 7.0 the panel sits under Website Tools.
2. Paste the script into HeaderUse the Header field. The panel has other fields, including a separate one for the order confirmation page. Leave those empty unless your tool asks for them.

   <script defer src="https://example.com/tool.js"></script>

   Copy

3. SaveClick Save. The script is on the site from that point.
4. Look at the site the way a visitor doesInjected code can run inside the editor preview, which makes the preview a poor test. Open your site’s URL in a private window instead.

• In a private window, view the source of any page and search for the script’s address inside the head.
• Open a second page and confirm the Network tab in developer tools shows the script there as well.

There is no Code Injection option

The site’s plan does not include it. Squarespace lists Core, Plus, Advanced and some legacy billing plans. Check which plan the site is on.

The script is missing on checkout

Squarespace states that checkout pages don’t support code. Plan around that; there is no setting that changes it.

It works in the editor and you call it done

Code running in the editor preview tells you little about what a visitor gets. Test in a private window on the real URL before telling anyone the install is finished.

Checked on 2026-11-11 against Squarespace Help Center: Using code injection.