diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 61cf7cf24..c1e32f8df 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -112,7 +112,7 @@ if(CLI11_SINGLE_FILE)
   if(CLI11_INSTALL)
     install(FILES "${PROJECT_BINARY_DIR}/include/CLI11.hpp"
             DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
-    configure_file("cmake/CLIsingle.hpp.in" "${PROJECT_BINARY_DIR}/include/CLI/CLI.hpp" @ONLY)
+    configure_file("${CLI11_SOURCE_DIR}/cmake/CLIsingle.hpp.in" "${PROJECT_BINARY_DIR}/include/CLI/CLI.hpp" @ONLY)
     install(FILES "${PROJECT_BINARY_DIR}/include/CLI/CLI.hpp"
             DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/CLI)
   endif()