How to fix mixed content on Squarespace

Steps for Squarespace

1. Squarespace enforces HTTPS automatically; mixed content almost always comes from custom code blocks or external embeds.
2. Go to Pages → click any page → Edit → find any Code Block or Embed Block, and check the HTML/code inside for http:// URLs. Replace with https://.
3. Check Website → Pages → Page Settings → Advanced (for individual pages) or Design → Custom CSS for any hardcoded http:// asset references.
4. In Settings → Advanced → Code Injection (Header / Footer), review any injected scripts or stylesheets for HTTP URLs and update them.
5. If you use third-party integrations (e.g. embedded maps, chat widgets) added via Extensions or Code Injection, get the HTTPS version of the embed code from the provider.
6. Republish or save your changes and check the site in an incognito browser with DevTools open (Console tab) to confirm the padlock is clean.

<meta http-equiv="Content-Security-Policy" content="upgrade-insecure-requests">

What is mixed content?

Mixed content happens when a web page is loaded securely over HTTPS but one or more of its resources — images, scripts, stylesheets, fonts, videos, iframes, or API calls — are still requested over plain HTTP. Browsers treat this as a security problem because the encrypted connection protecting your page can be undermined by an unencrypted resource. There are two kinds: "passive" mixed content (images, audio, video) which browsers may still display but flag with a warning, and "active" mixed content (scripts, stylesheets, iframes) which modern browsers block entirely, breaking functionality. A clean HTTPS store means every single request on every page uses HTTPS — no exceptions.

Mixed content directly harms your store in four ways. First, browsers show a "Not Secure" warning or remove the padlock icon, which destroys shopper trust and causes cart abandonment — studies consistently show customers abandon checkout when they see security warnings. Second, blocked active mixed content (a blocked script or stylesheet) can silently break your add-to-cart button, checkout form, live chat widget, or payment processor embed, costing you direct revenue with no obvious error message to trace. Third, Google has stated that HTTPS is a ranking signal; mixed-content warnings can undermine that signal and signal a poorly maintained site. Fourth, if your store is subject to PCI-DSS (required for card payments), serving payment-related resources over HTTP is a compliance violation that can result in fines or loss of payment processing privileges.

See the complete Mixed content guide for every platform and the full background.