diff --git a/CMakeLists.txt b/CMakeLists.txt
index 54c8d63a..5b45f594 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -51,7 +51,7 @@ add_definitions(-DIQ_TREE)
 # The version number.
 set (iqtree_VERSION_MAJOR 1)
 set (iqtree_VERSION_MINOR 6)
-set (iqtree_VERSION_PATCH "8")
+set (iqtree_VERSION_PATCH "9")
 
 set(BUILD_SHARED_LIBS OFF)