diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0a6ae8e8dd8e1e..f73ce51e8cf583 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,9 +2,9 @@
 
 Select a Node.js version below to view the changelog history:
 
-* [Node.js 20](doc/changelogs/CHANGELOG_V20.md) **Current**
+* [Node.js 20](doc/changelogs/CHANGELOG_V20.md) **Long Term Support**
 * [Node.js 19](doc/changelogs/CHANGELOG_V19.md) **Current**
-* [Node.js 18](doc/changelogs/CHANGELOG_V18.md) **Long Term Support**
+* [Node.js 18](doc/changelogs/CHANGELOG_V18.md) Long Term Support
 * [Node.js 17](doc/changelogs/CHANGELOG_V17.md) End-of-Life
 * [Node.js 16](doc/changelogs/CHANGELOG_V16.md) End-of-Life
 * [Node.js 15](doc/changelogs/CHANGELOG_V15.md) End-of-Life
@@ -29,14 +29,15 @@ release.
 
 <table>
 <tr>
-  <th title="Current"><a href="doc/changelogs/CHANGELOG_V20.md">20</a> (Current)</th>
+  <th title="LTS Until 2026-04"><a href="doc/changelogs/CHANGELOG_V20.md">20</a> (LTS)</th>
   <th title="Current"><a href="doc/changelogs/CHANGELOG_V19.md">19</a> (Current)</th>
   <th title="LTS Until 2025-04"><a href="doc/changelogs/CHANGELOG_V18.md">18</a> (LTS)</th>
   <th title="LTS Until 2023-09"><a href="doc/changelogs/CHANGELOG_V16.md">16</a> (LTS)</th>
 </tr>
 <tr>
   <td valign="top">
-<b><a href="doc/changelogs/CHANGELOG_V20.md#20.8.1">20.8.1</a></b><br/>
+<b><a href="doc/changelogs/CHANGELOG_V20.md#20.9.0">20.9.0</a></b><br/>
+<a href="doc/changelogs/CHANGELOG_V20.md#20.8.1">20.8.1</a><br/>
 <a href="doc/changelogs/CHANGELOG_V20.md#20.8.0">20.8.0</a><br/>
 <a href="doc/changelogs/CHANGELOG_V20.md#20.7.0">20.7.0</a><br/>
 <a href="doc/changelogs/CHANGELOG_V20.md#20.6.1">20.6.1</a><br/>
diff --git a/doc/changelogs/CHANGELOG_V20.md b/doc/changelogs/CHANGELOG_V20.md
index 471eb83156cb7e..e97d6ce631993b 100644
--- a/doc/changelogs/CHANGELOG_V20.md
+++ b/doc/changelogs/CHANGELOG_V20.md
@@ -4,10 +4,14 @@
 
 <table>
 <tr>
+<th>LTS 'Iron'</th>
 <th>Current</th>
 </tr>
 <tr>
 <td>
+<a href="#20.9.0">20.9.0</a><br/>
+</td>
+<td>
 <a href="#20.8.1">20.8.1</a><br/>
 <a href="#20.8.0">20.8.0</a><br/>
 <a href="#20.7.0">20.7.0</a><br/>
@@ -47,6 +51,24 @@
   * [io.js](CHANGELOG_IOJS.md)
   * [Archive](CHANGELOG_ARCHIVE.md)
 
+<a id="20.9.0"></a>
+
+## 2023-10-24, Version 20.9.0 'Iron' (LTS), @richardlau
+
+### Notable Changes
+
+This release marks the transition of Node.js 20.x into Long Term Support (LTS)
+with the codename 'Iron'. The 20.x release line now moves into "Active LTS"
+and will remain so until October 2024. After that time, it will move into
+"Maintenance" until end of life in April 2026.
+
+### Known issue
+
+Collecting code coverage via the `NODE_V8_COVERAGE` environment variable may
+lead to a hang. This is not thought to be a regression in Node.js 20 (some
+reports are on Node.js 18). For more information, including some potential
+workarounds, see issue [#49344](https://github.com/nodejs/node/issues/49344).
+
 <a id="20.8.1"></a>
 
 ## 2023-10-13, Version 20.8.1 (Current), @RafaelGSS
diff --git a/src/node_version.h b/src/node_version.h
index 1826f5cead252d..49ee116668763b 100644
--- a/src/node_version.h
+++ b/src/node_version.h
@@ -23,13 +23,13 @@
 #define SRC_NODE_VERSION_H_
 
 #define NODE_MAJOR_VERSION 20
-#define NODE_MINOR_VERSION 8
-#define NODE_PATCH_VERSION 2
+#define NODE_MINOR_VERSION 9
+#define NODE_PATCH_VERSION 0
 
-#define NODE_VERSION_IS_LTS 0
-#define NODE_VERSION_LTS_CODENAME ""
+#define NODE_VERSION_IS_LTS 1
+#define NODE_VERSION_LTS_CODENAME "Iron"
 
-#define NODE_VERSION_IS_RELEASE 0
+#define NODE_VERSION_IS_RELEASE 1
 
 #ifndef NODE_STRINGIFY
 #define NODE_STRINGIFY(n) NODE_STRINGIFY_HELPER(n)
diff --git a/test/parallel/test-process-release.js b/test/parallel/test-process-release.js
index 4455ad9ca23c64..98a089a8f9ef5a 100644
--- a/test/parallel/test-process-release.js
+++ b/test/parallel/test-process-release.js
@@ -25,6 +25,8 @@ if (versionParts[0] === '4' && versionParts[1] >= 2) {
   assert.strictEqual(process.release.lts, 'Gallium');
 } else if (versionParts[0] === '18' && versionParts[1] >= 12) {
   assert.strictEqual(process.release.lts, 'Hydrogen');
+} else if (versionParts[0] === '20' && versionParts[1] >= 9) {
+  assert.strictEqual(process.release.lts, 'Iron');
 } else {
   assert.strictEqual(process.release.lts, undefined);
 }