Shopify how-to July 15, 2026 3 min read
How to Add a Size Chart to Shopify Checkout Extensions (Plus)
Final size verification at checkout. Plus only. 3-5% extra return reduction.
The Setup
Shopify Plus admin → Checkout → Customize → Apps → Tailor Size Guide. Drop the "Verify size" block into the checkout summary section. Preview, save, publish.
What Customers See
"Verify size" link beside each line item. Click → modal with the relevant chart. Confirm or modify size. Update cart. Continue checkout.
Plus Only
Checkout UI Extensions require Shopify Plus. On non-Plus plans, use cart-page size verification instead — different surface, same effect.
FAQs
Checkout size chart?
Yes — Plus only.
Return reduction?
3-5% on top of product-page charts.
Final-mile size verification
Tailor Size Guide ships a Plus Checkout UI Extension.