diff --git a/CHANGELOG.md b/CHANGELOG.md
index fc0da90b71..c7cdc2336f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,23 @@
+# [12.0.0](https://github.com/elastic/elastic-charts/compare/v11.2.0...v12.0.0) (2019-09-11)
+
+
+### Features
+
+* **theme:** add gridLineStyle to AxisConfig ([#257](https://github.com/elastic/elastic-charts/issues/257)) ([97dd812](https://github.com/elastic/elastic-charts/commit/97dd812)), closes [#237](https://github.com/elastic/elastic-charts/issues/237)
+
+
+### BREAKING CHANGES
+
+* **theme:** Added `GridLineStyle` to `Theme` (`theme.gridLineStyle.horizontal` and `theme.gridLineStyle.vertical`)
+
+* add gridLineStyle to AxisConfig
+* add chartTheme vs axisSpec
+* add gridLineStyle for theme or spec
+* merge gridLineConfig from theme with axisSpec
+* add visible key to GridLineConfig
+* specify theme styling per axis in story
+* add gridLineStyle theme with horiz and vert
+
 # [11.2.0](https://github.com/elastic/elastic-charts/compare/v11.1.2...v11.2.0) (2019-09-04)
 
 
diff --git a/package.json b/package.json
index 65c796a89f..5db4784bee 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@elastic/charts",
   "description": "Elastic-Charts data visualization library",
-  "version": "11.2.0",
+  "version": "12.0.0",
   "author": "Marco Vettorello <marco.vettorello@elastic.co>",
   "license": "Apache-2.0",
   "main": "dist/index.js",