diff --git a/package-lock.json b/package-lock.json
index d9202ec..69d88a9 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "timezone-groups",
-  "version": "0.3.0",
+  "version": "0.4.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "timezone-groups",
-      "version": "0.3.0",
+      "version": "0.4.0",
       "bin": {
         "timezone-groups": "dist/cli.cjs"
       },
diff --git a/package.json b/package.json
index 00a4754..273954f 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "timezone-groups",
-  "version": "0.3.0",
+  "version": "0.4.0",
   "description": "A JavaScript library to group time zones based on dates (DST-aware).",
   "main": "./dist/index.js",
   "module": "./dist/index.js",