diff --git a/CMakeLists.txt b/CMakeLists.txt
index d80cabd..1350fb6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -24,7 +24,7 @@ endif()
 
 option(MATRIXSSL_BUILD_SHARED "Build MatrixSSL as a shared library" ON)
 option(MATRIXSSL_BUILD_STATIC "Build MatrixSSL as a static library" OFF)
-option(MATRIXSSL_DISABLE_TLS13 "Disable TLS 1.3 in the generated CMake configuration" ON)
+option(MATRIXSSL_DISABLE_TLS13 "Disable TLS 1.3 in the generated CMake configuration" OFF)
 option(MATRIXSSL_BUILD_OPENSSL_COMPAT "Build the mars-nwe reduced OpenSSL compatibility layer" ON)
 option(MATRIXSSL_BUILD_TESTS "Build MatrixSSL test programs matching the GNUmakefile tests target" ${MATRIXSSL_DEFAULT_BUILD_PROGRAMS})
 option(MATRIXSSL_BUILD_APPS "Build MatrixSSL example applications matching the GNUmakefile apps target" ${MATRIXSSL_DEFAULT_BUILD_PROGRAMS})