diff --git a/CHANGELOG.md b/CHANGELOG.md
index e3501042..b6adca15 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,9 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+### Fixed
+
+- `undefined` postal code mask causing `address-form` to break.
 
 ## [4.4.0] - 2020-01-02
 
diff --git a/demo/src/Container.js b/demo/src/Container.js
index 160bf08f..7ecdf425 100644
--- a/demo/src/Container.js
+++ b/demo/src/Container.js
@@ -26,6 +26,7 @@ const shipsTo = [
   'URY',
   'USA',
   'VEN',
+  'ITA',
 ]
 
 class Container extends Component {
diff --git a/react/transforms/utils.js b/react/transforms/utils.js
index e2388743..1fb2b0f8 100644
--- a/react/transforms/utils.js
+++ b/react/transforms/utils.js
@@ -1,3 +1,3 @@
 export function removeNonWords(string) {
-  return string.replace(/\W/g, '')
+  return string && string.replace(/\W/g, '')
 }