diff --git a/tools/FindPythonLibsNew.cmake b/tools/FindPythonLibsNew.cmake
index 992f9f52a9..8275b9d5aa 100644
--- a/tools/FindPythonLibsNew.cmake
+++ b/tools/FindPythonLibsNew.cmake
@@ -188,13 +188,20 @@ _pybind11_get_if_undef(_PYTHON_VALUES 0 _PYTHON_VERSION_LIST)
 _pybind11_get_if_undef(_PYTHON_VALUES 1 PYTHON_PREFIX)
 _pybind11_get_if_undef(_PYTHON_VALUES 2 PYTHON_INCLUDE_DIR)
 _pybind11_get_if_undef(_PYTHON_VALUES 3 PYTHON_SITE_PACKAGES)
-_pybind11_get_if_undef(_PYTHON_VALUES 4 PYTHON_MODULE_EXTENSION)
 _pybind11_get_if_undef(_PYTHON_VALUES 5 PYTHON_IS_DEBUG)
 _pybind11_get_if_undef(_PYTHON_VALUES 6 PYTHON_SIZEOF_VOID_P)
 _pybind11_get_if_undef(_PYTHON_VALUES 7 PYTHON_LIBRARY_SUFFIX)
 _pybind11_get_if_undef(_PYTHON_VALUES 8 PYTHON_LIBDIR)
 _pybind11_get_if_undef(_PYTHON_VALUES 9 PYTHON_MULTIARCH)
 
+list(GET _PYTHON_VALUES 4 _PYTHON_MODULE_EXT_SUFFIX)
+if(PYBIND11_PYTHONLIBS_OVERWRITE OR NOT DEFINED PYTHON_MODULE_DEBUG_POSTFIX)
+  get_filename_component(PYTHON_MODULE_DEBUG_POSTFIX "${_PYTHON_MODULE_EXT_SUFFIX}" NAME_WE)
+endif()
+if(PYBIND11_PYTHONLIBS_OVERWRITE OR NOT DEFINED PYTHON_MODULE_EXTENSION)
+  get_filename_component(PYTHON_MODULE_EXTENSION "${_PYTHON_MODULE_EXT_SUFFIX}" EXT)
+endif()
+
 # Make sure the Python has the same pointer-size as the chosen compiler
 # Skip if CMAKE_SIZEOF_VOID_P is not defined
 # This should be skipped for (non-Apple) cross-compiles (like EMSCRIPTEN)
diff --git a/tools/pybind11NewTools.cmake b/tools/pybind11NewTools.cmake
index 3a35a73863..8cee2d4609 100644
--- a/tools/pybind11NewTools.cmake
+++ b/tools/pybind11NewTools.cmake
@@ -95,25 +95,36 @@ endif()
 
 # Get the suffix - SO is deprecated, should use EXT_SUFFIX, but this is
 # required for PyPy3 (as of 7.3.1)
-if(NOT DEFINED PYTHON_MODULE_EXTENSION)
+if(NOT DEFINED PYTHON_MODULE_EXTENSION OR NOT DEFINED PYTHON_MODULE_DEBUG_POSTFIX)
   execute_process(
     COMMAND
       "${${_Python}_EXECUTABLE}" "-c"
       "import sys, importlib; s = importlib.import_module('distutils.sysconfig' if sys.version_info < (3, 10) else 'sysconfig'); print(s.get_config_var('EXT_SUFFIX') or s.get_config_var('SO'))"
-    OUTPUT_VARIABLE _PYTHON_MODULE_EXTENSION
-    ERROR_VARIABLE _PYTHON_MODULE_EXTENSION_ERR
+    OUTPUT_VARIABLE _PYTHON_MODULE_EXT_SUFFIX
+    ERROR_VARIABLE _PYTHON_MODULE_EXT_SUFFIX_ERR
     OUTPUT_STRIP_TRAILING_WHITESPACE)
 
-  if(_PYTHON_MODULE_EXTENSION STREQUAL "")
+  if(_PYTHON_MODULE_EXT_SUFFIX STREQUAL "")
     message(
       FATAL_ERROR "pybind11 could not query the module file extension, likely the 'distutils'"
-                  "package is not installed. Full error message:\n${_PYTHON_MODULE_EXTENSION_ERR}")
+                  "package is not installed. Full error message:\n${_PYTHON_MODULE_EXT_SUFFIX_ERR}"
+    )
   endif()
 
   # This needs to be available for the pybind11_extension function
-  set(PYTHON_MODULE_EXTENSION
-      "${_PYTHON_MODULE_EXTENSION}"
-      CACHE INTERNAL "")
+  if(NOT DEFINED PYTHON_MODULE_DEBUG_POSTFIX)
+    get_filename_component(_PYTHON_MODULE_DEBUG_POSTFIX "${_PYTHON_MODULE_EXT_SUFFIX}" NAME_WE)
+    set(PYTHON_MODULE_DEBUG_POSTFIX
+        "${_PYTHON_MODULE_DEBUG_POSTFIX}"
+        CACHE INTERNAL "")
+  endif()
+
+  if(NOT DEFINED PYTHON_MODULE_EXTENSION)
+    get_filename_component(_PYTHON_MODULE_EXTENSION "${_PYTHON_MODULE_EXT_SUFFIX}" EXT)
+    set(PYTHON_MODULE_EXTENSION
+        "${_PYTHON_MODULE_EXTENSION}"
+        CACHE INTERNAL "")
+  endif()
 endif()
 
 # Python debug libraries expose slightly different objects before 3.8
@@ -253,6 +264,9 @@ endfunction()
 
 function(pybind11_extension name)
   # The extension is precomputed
-  set_target_properties(${name} PROPERTIES PREFIX "" SUFFIX "${PYTHON_MODULE_EXTENSION}")
-
+  set_target_properties(
+    ${name}
+    PROPERTIES PREFIX ""
+               DEBUG_POSTFIX "${PYTHON_MODULE_DEBUG_POSTFIX}"
+               SUFFIX "${PYTHON_MODULE_EXTENSION}")
 endfunction()
diff --git a/tools/pybind11Tools.cmake b/tools/pybind11Tools.cmake
index 67e710bda5..1b1774d09e 100644
--- a/tools/pybind11Tools.cmake
+++ b/tools/pybind11Tools.cmake
@@ -65,6 +65,7 @@ _pybind11_promote_to_cache(PYTHON_INCLUDE_DIRS)
 _pybind11_promote_to_cache(PYTHON_LIBRARIES)
 _pybind11_promote_to_cache(PYTHON_MODULE_PREFIX)
 _pybind11_promote_to_cache(PYTHON_MODULE_EXTENSION)
+_pybind11_promote_to_cache(PYTHON_MODULE_DEBUG_POSTFIX)
 _pybind11_promote_to_cache(PYTHON_VERSION_MAJOR)
 _pybind11_promote_to_cache(PYTHON_VERSION_MINOR)
 _pybind11_promote_to_cache(PYTHON_VERSION)
@@ -148,8 +149,11 @@ endif()
 
 function(pybind11_extension name)
   # The prefix and extension are provided by FindPythonLibsNew.cmake
-  set_target_properties(${name} PROPERTIES PREFIX "${PYTHON_MODULE_PREFIX}"
-                                           SUFFIX "${PYTHON_MODULE_EXTENSION}")
+  set_target_properties(
+    ${name}
+    PROPERTIES PREFIX "${PYTHON_MODULE_PREFIX}"
+               DEBUG_POSTFIX "${PYTHON_MODULE_DEBUG_POSTFIX}"
+               SUFFIX "${PYTHON_MODULE_EXTENSION}")
 endfunction()
 
 # Build a Python extension module: