WooCommerce developers customized checkout extensively: WooCommerce Checkout Field Editor added custom fields, conditional logic showed/hid fields based on products, and custom PHP hooks like woocommerce_checkout_before_order_review injected arbitrary HTML at any checkout position. Shopify's checkout is hosted and far more restricted — but Checkout UI Extensions (introduced in 2023) and the Checkout Blocks app give significant customization capability without requiring Shopify Plus.

WooCommerce checkout customization vs Shopify

WooCommerce approach	Shopify equivalent	Requires
WC Checkout Field Editor (custom fields)	Checkout UI Extension or Checkout Blocks app	Standard Shopify or Plus
Order notes field	Native order notes (enable in theme settings) or Checkout Blocks	Standard Shopify
Delivery date picker	Checkout UI Extension (custom) or app (DeliveryDate, Zapiet)	Standard Shopify
Custom HTML at checkout	Checkout UI Extension components only	Standard Shopify
checkout.php full customization	checkout.liquid (deprecated) or Checkout UI Extensions	Shopify Plus
Custom checkout steps / multi-page	Not supported (Shopify checkout is fixed flow)	N/A
Conditional field display	Checkout UI Extension with React logic	Standard Shopify
Order bump / upsell at checkout	Checkout UI Extension or Post-purchase extension	Standard Shopify
Trust badges at checkout	Checkout Blocks or Checkout UI Extension	Standard Shopify

Checkout Blocks app (no-code, standard Shopify)

Checkout Blocks is a free/paid Shopify app that adds blocks to checkout without code — the fastest way to replicate many WooCommerce checkout customizations:

Available blocks: text field, text area, checkbox, dropdown, date picker, image, text, banner, upsell product, trust badge, delivery date, gift message, custom HTML banner
Placement: can be placed at address step, delivery step, payment step, order confirmation page
Conditional display: show blocks based on cart contents, product tags, cart total, customer tags
Data saved: custom field values saved as order metafields (accessible in admin, order confirmation, fulfilment)
Free tier: limited blocks. Paid: ~$15–99/mo depending on features needed.

Native order notes

Shopify themes can enable an order notes field in cart — not technically "checkout" but functionally equivalent for many WooCommerce order notes use cases:

Enable via theme settings: Dawn → Cart → enable "Order note"
Notes appear on the order in admin and in order confirmation email
Limitation: customers enter notes in cart, not checkout — some drop off before reaching checkout
For notes at checkout specifically: use Checkout Blocks "text area" block at the delivery or payment step

Checkout UI Extensions (developer approach)

For custom checkout fields beyond what Checkout Blocks offers, developers build Checkout UI Extensions using Shopify's React-based extension API:

// checkout-extension/src/Checkout.tsx
import {
  reactExtension,
  useApplyMetafieldsChange,
  useMetafield,
  TextField,
  BlockStack,
  Text,
} from "@shopify/ui-extensions-react/checkout";

export default reactExtension("purchase.checkout.delivery-address.render-after", () => (
  <DeliveryInstructions />
));

function DeliveryInstructions() {
  const applyMetafieldsChange = useApplyMetafieldsChange();
  const currentValue = useMetafield({
    namespace: "custom",
    key: "delivery_instructions",
  });

  return (
    <BlockStack>
      <Text size="medium">Delivery instructions (optional)</Text>
      <TextField
        label="e.g. Leave at door, ring bell"
        value={currentValue?.value ?? ""}
        onChange={(value) =>
          applyMetafieldsChange({
            type: "updateMetafield",
            namespace: "custom",
            key: "delivery_instructions",
            valueType: "string",
            value,
          })
        }
      />
    </BlockStack>
  );
}

Extension target positions

purchase.checkout.contact.render-after — after email/contact field
purchase.checkout.delivery-address.render-after — after delivery address
purchase.checkout.shipping-option-list.render-after — after shipping options
purchase.checkout.payment-method-list.render-after — after payment methods
purchase.checkout.actions.render-before — before "Complete order" button
purchase.thank-you.block.render — on thank you / order confirmation page

Checkout upsells

In-checkout upsell (Checkout UI Extension)

Show a relevant product recommendation at checkout ("Add X for £Y before completing your order")
One-click add to cart from checkout extension
Conditional: only show if cart doesn't contain the product, or if cart total is above/below threshold
Apps: Checkout Blocks includes upsell block. Dedicated apps: ReConvert, Upsell by Zipify.

Post-purchase upsell (thank you page)

Offer shown on the order confirmation page after payment — customer can add product to their existing order
No re-entering payment details — charged to same payment method
Best for low-friction add-ons (related product, extended warranty, bundled accessory)
Apps: ReConvert, Zipify One-Click Upsell, Checkout Blocks thank-you page block

Delivery date picker

WooCommerce stores commonly used WooCommerce Delivery Date or Iconic WooCommerce Delivery Slots. Shopify equivalents:

Zapiet Store Pickup + Delivery: Full delivery date/time slot management. Integrates with checkout for date selection. Supports local delivery and store pickup with date/time slots.
DeliveryDate: Delivery date picker at checkout via Checkout UI Extension. Block-based, configurable blackout dates and lead times.
Checkout Blocks: Date picker block available on paid plan.
Date saved as order metafield: accessible in fulfilment workflow, order confirmation email, and third-party fulfilment systems.

Trust signals at checkout

WooCommerce checkout often had trust badges injected via hooks. Shopify checkout equivalent:

Checkout Blocks: add trust badge image (SSL secure, money-back guarantee, etc.) at payment step
Custom banner: "Free returns within 30 days" banner above the "Complete order" button
Checkout Blocks free tier includes basic text and image blocks — sufficient for trust signals

Shopify Plus: checkout.liquid (legacy) and checkout editor

Shopify Plus merchants have additional options:

Checkout editor (Plus): drag-and-drop checkout customization including custom HTML blocks, branding, and more section types
checkout.liquid (deprecated but still functional): Liquid template for checkout — full HTML control. Being phased out in favour of Checkout UI Extensions + editor.
New Plus stores should use Checkout UI Extensions + the checkout editor rather than checkout.liquid.

Checkout migration checklist

Audit current WooCommerce checkout customizations: custom fields, notes, conditional logic, upsells
Map each WooCommerce customization to Shopify equivalent (Checkout Blocks or UI Extension)
Install Checkout Blocks app for no-code customizations (order notes, trust badges, gift message)
Build Checkout UI Extension for custom fields not available in Checkout Blocks
Set up delivery date/time picker if applicable (Zapiet or DeliveryDate)
Configure post-purchase upsell on thank-you page
Verify all custom field values are saved as order metafields and accessible in fulfilment workflow
Ensure order confirmation email template includes custom field values (configure in email template settings)
Test complete checkout flow with all custom fields on mobile and desktop

The most critical checkout customization for most WooCommerce migrators is the order notes or delivery instructions field — customers are used to it being there, and losing it causes customer service overhead as buyers email to add instructions manually. This is a 10-minute Checkout Blocks setup: install the free tier, add a text area block to the delivery step, label it "Delivery instructions or order notes". The field value appears on the order in admin automatically. Don't over-engineer this particular feature — Checkout Blocks handles it cleanly without any code.

Shopify checkout extensions after WooCommerce (2026)