diff --git a/instrumentation-genai/opentelemetry-instrumentation-google-genai/CHANGELOG.md b/instrumentation-genai/opentelemetry-instrumentation-google-genai/CHANGELOG.md
index cebe7b92e5..187c110e4a 100644
--- a/instrumentation-genai/opentelemetry-instrumentation-google-genai/CHANGELOG.md
+++ b/instrumentation-genai/opentelemetry-instrumentation-google-genai/CHANGELOG.md
@@ -5,7 +5,7 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## Unreleased
+## Version 0.4b0 (2025-10-16)
 
 - Implement the new semantic convention changes made in https://github.com/open-telemetry/semantic-conventions/pull/2179.
 A single event (`gen_ai.client.inference.operation.details`) is used to capture Chat History. This is opt-in,
diff --git a/instrumentation-genai/opentelemetry-instrumentation-google-genai/src/opentelemetry/instrumentation/google_genai/version.py b/instrumentation-genai/opentelemetry-instrumentation-google-genai/src/opentelemetry/instrumentation/google_genai/version.py
index 5d5d35851a..af6f95acde 100644
--- a/instrumentation-genai/opentelemetry-instrumentation-google-genai/src/opentelemetry/instrumentation/google_genai/version.py
+++ b/instrumentation-genai/opentelemetry-instrumentation-google-genai/src/opentelemetry/instrumentation/google_genai/version.py
@@ -17,4 +17,4 @@
 #   This version should stay below "1.0" until the fundamentals
 #   in "TODOS.md" have been addressed. Please revisit the TODOs
 #   listed there before bumping to a stable version.
-__version__ = "0.4b0.dev"
+__version__ = "0.4b0"