WooCommerce: Change Input Type @ Checkout Fields

This challenging task (yet very simple at the end) was requested by one of my US clients. As they trade in the USA only, they wanted to force “numbers only” in the ZIP input field, so that letters would not be allowed. And WooCommerce doesn’t do this out of the box.

So, let’s fix this – enjoy!

PHP Snippet: Change ZIP Field to Input Type = Number @ WooCommerce Checkout

/**
 * @snippet       Change a Checkout Field Input Type
 * @how-to        Get CustomizeWoo.com FREE
 * @author        Rodolfo Melogli
 * @compatible    WooCommerce 8
 * @community     Join https://businessbloomer.com/club/
 */

add_filter( 'woocommerce_checkout_fields', 'bbloomer_checkout_field_type', 9999 );

function bbloomer_checkout_field_type( $fields ) {
	$fields['billing']['billing_postcode']['type'] = 'number';
	$fields['shipping']['shipping_postcode']['type'] = 'number';	
	return $fields;
}

Where to add custom code?

You should place custom PHP in functions.php and custom CSS in style.css of your child theme: where to place WooCommerce customization?

This code still works, unless you report otherwise. To exclude conflicts, temporarily switch to the Storefront theme, disable all plugins except WooCommerce, and test the snippet again: WooCommerce troubleshooting 101

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Rodolfo Melogli

Business Bloomer Founder

Author, WooCommerce expert and WordCamp speaker, Rodolfo has worked as an independent WooCommerce freelancer since 2011. His goal is to help entrepreneurs and developers overcome their WooCommerce nightmares. Rodolfo loves travelling, chasing tennis & soccer balls and, of course, wood fired oven pizza. Follow @rmelogli