Order Summary Items filter » subtotalPriceFormat

snippet.js

const { registerCheckoutFilters } = window.wc.blocksCheckout;

// Adjust subtotal price format of the order summary items.
registerCheckoutFilters( 'example-extension', {
  subtotalPriceFormat: ( value, extensions, args ) => {
    // Return early since this filter is not being applied in the Summary context.
    // We must return the original value we received here.
    if ( args?.context !== 'summary' ) {
      return value;
    }
    return '<price/> per item';
  }
} );