diff --git a/CMakeLists.txt b/CMakeLists.txt
index 37174eb23..1adc5da50 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.13)
+cmake_minimum_required(VERSION 3.9)
 
 option(BUILD_DEPS "Builds aws common runtime dependencies as part of build. Turn off if you want to control your dependency chain." ON)
 option(BYO_CRYPTO "Don't build a tls implementation or link against a crypto interface. This feature is only for unix builds currently" OFF)