Checkout Extensibility
Checkout Extensibility is Shopify's system for customizing the checkout experience using Checkout UI Extensions — code that runs inside the Shopify checkout without requiring scripts in the checkout.liquid file. It replaced the older checkout.liquid customization method and is required for all Shopify Plus stores.
Why It Matters for Shopify Stores
Checkout is where the sale happens. Checkout Extensibility allows merchants to add trust badges, upsells, custom form fields, and branded elements to the checkout without compromising Shopify's PCI compliance or performance guarantees. Unlike checkout.liquid scripts (which could slow the checkout page), Checkout Extensions load efficiently and are sandboxed. For merchants missing payment icons, trust badges, or custom fields at checkout, Checkout Extensibility is the correct modern solution.
How to Check Your Store
In Shopify Admin > Settings > Checkout. If you see 'Upgrade to extensible checkout' or you're on Shopify Plus, Checkout Extensibility is available. Apps offering checkout customization will use the Checkout Extensions system.
Use the free shopify checkout trust audit toolHow to Fix It
Use apps that support Checkout Extensibility (they'll show a 'Checkout Extension' label in the App Store) rather than legacy checkout.liquid scripts. This ensures compatibility with future Shopify versions.
Related Terms
Shopify Theme
ShopifyA Shopify theme is the visual and structural template that controls how your store looks and functions.
Online Store 2.0
ShopifyOnline Store 2.
Conversion Rate
Trust & CROConversion rate is the percentage of store visitors who complete a purchase.
Trust Badges
Trust & CROTrust badges are visual elements displayed on product and checkout pages that reassure buyers about the safety and reliability of their purchase.
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