What's the difference between a Squarespace plugin and a Squarespace extension?
A Squarespace plugin is a third-party code-based add-on you install yourself via Code Injection or a Code Block — typically adding features like filtering, tables, or maps. A Squarespace extension is an official integration listed in Squarespace's Extensions directory, which connects your site to external services and is mostly focused on commerce, shipping, and marketing tools.
Plugins: code you add yourself
A Squarespace plugin is a code-based add-on built by a third party (such as Squarewebsites) that you install by pasting a snippet into Code Injection or a Code Block (Squarewebsites). Plugins add front-end features the platform lacks natively — filtering, sortable tables, multi-location maps, lazy-loaded summaries, and so on. You control the code directly and can remove it at any time — this is the custom-code path Squarespace documents for its plans (Squarespace).
Extensions: official service integrations
A Squarespace extension is an integration listed in Squarespace’s official Extensions directory, which connects your site to external services and is mostly focused on commerce, shipping, and marketing tools (Squarewebsites). Extensions are installed through Squarespace’s own dashboard rather than as pasted code, and Squarespace documents them in its official Extensions article (Squarespace).
Which one do you need
If you want to add a feature Squarespace doesn’t offer natively — like multi-filter search or real tables — you need a third-party plugin. If you want to connect your store to a shipping, accounting, or marketing service, check the official Extensions directory first, since those integrations are maintained by Squarespace partners (Squarewebsites).
See the full Squarespace Plugins — General product page on squarewebsites.org for live pricing, demos, and setup details.
Sources: squarewebsites.org · squarewebsites.org · support.squarespace.com · support.squarespace.com