diff --git a/includes/class-wc-validation.php b/includes/class-wc-validation.php
index 5b0248e2e5d..82d11138af7 100644
--- a/includes/class-wc-validation.php
+++ b/includes/class-wc-validation.php
@@ -80,7 +80,7 @@ class WC_Validation {
 				$valid = (bool) preg_match( '/([AC-FHKNPRTV-Y]\d{2}|D6W)[0-9AC-FHKNPRTV-Y]{4}/', wc_normalize_postcode( $postcode ) );
 				break;
 			case 'JP':
-				$valid = (bool) preg_match( '/^([0-9]{3})([-])([0-9]{4})$/', $postcode );
+				$valid = (bool) preg_match( '/^([0-9]{3})([-]?)([0-9]{4})$/', $postcode );
 				break;
 			case 'PT':
 				$valid = (bool) preg_match( '/^([0-9]{4})([-])([0-9]{3})$/', $postcode );