diff --git a/CHANGES.md b/CHANGES.md
index 57ac620b..303dac86 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,4 +1,4 @@
-### 3.4.0 - in development
+### 3.4.0 - 2023-04-14
 
 - Fix exception `__cause__` not being propagated with
   `tblib.pickling_support.install()`. (#255).
diff --git a/loky/__init__.py b/loky/__init__.py
index 2d5c0810..e9df6869 100644
--- a/loky/__init__.py
+++ b/loky/__init__.py
@@ -41,4 +41,4 @@
 ]
 
 
-__version__ = "3.4.0.dev0"
+__version__ = "3.4.0"