FunnelKit Checkout Email Validation (domain based)

gistfile1.txt

/**
 * Block temporary/disposable email domains during WooCommerce checkout
 * Add this to your theme's functions.php file
 */

// Blocked email domains list
function fk_wc_get_blocked_email_domains() {
	$domains = array(
		'mailnetter.com',
		'mailnetter.net',
		'mailnetter.org',
		'10minutemail.com',
		'guerrillamail.com',
		'mailinator.com',
		'temp-mail.org',
		'tempmail.com',
		'yopmail.com',
		'throwaway.email',
		'trashmail.com',
		'getnada.com',
		'dispostable.com',
		'mohmal.com',
		'spamgourmet.com',
		'maildrop.cc',
		'sharklasers.com',
	);
	return apply_filters( 'fk_wc_blocked_email_domains', $domains );
}

// Validate email domain during checkout
function fk_wc_validate_email_domain( $data, $errors ) {
	try {
		$email = isset( $data['billing_email'] ) ? sanitize_email( $data['billing_email'] ) : '';

		if ( empty( $email ) ) {
			return;
		}

		$email_parts = explode( '@', $email );
		if ( count( $email_parts ) !== 2 ) {
			return;
		}

		$domain = strtolower( trim( $email_parts[1] ) );
		$blocked_domains = fk_wc_get_blocked_email_domains();

		if ( in_array( $domain, $blocked_domains, true ) ) {
			$errors->add(
				'billing_email_validation',
				__( 'Sorry, we do not accept temporary or disposable email addresses. Please use a valid email address.', 'woocommerce' ),
				array( 'id' => 'billing_email' )
			);
		}
	} catch ( Exception $e ) {
		// Silently fail to avoid breaking checkout
		return;
	}
}

add_action( 'woocommerce_after_checkout_validation', 'fk_wc_validate_email_domain', 10, 2 );