WooCommerce - Remove subtotal row.

gistfile1.txt

add_filter( 'woocommerce_get_order_item_totals', 'adjust_woocommerce_get_order_item_totals' );

function adjust_woocommerce_get_order_item_totals( $totals ) {
  unset($totals['cart_subtotal']  );
  return $totals;
}

@jaibojo

To remove Subtotal row (in mobile also) add this code to style.css
.cart-subtotal { display: none !important; }

This is the answer for removing the subtotal from the cart and checkout pages
https://stackoverflow.com/questions/53277895/remove-subtotal-line-from-cart-and-checkout-pages-in-woocommerce