diff --git a/Misc/NEWS b/Misc/NEWS
index 52bbd04e7bb..24cec9d0e8d 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -298,6 +298,8 @@ Windows
 Tools/Demos
 -----------
 
+- Issue #25440: Fix output of python-config --extension-suffix.
+
 - Issue #25154: The pyvenv script has been deprecated in favour of
   `python3 -m venv`.
 
diff --git a/Misc/python-config.sh.in b/Misc/python-config.sh.in
index 64c81e5f74b..30c69278710 100644
--- a/Misc/python-config.sh.in
+++ b/Misc/python-config.sh.in
@@ -49,7 +49,7 @@ PY_ENABLE_SHARED="@PY_ENABLE_SHARED@"
 LDVERSION="@LDVERSION@"
 LIBDEST=${prefix}/lib/python${VERSION}
 LIBPL=$(echo "@LIBPL@" | sed "s#$prefix_build#$prefix_real#")
-SO="@SO@"
+SO="@EXT_SUFFIX@"
 PYTHONFRAMEWORK="@PYTHONFRAMEWORK@"
 INCDIR="-I$includedir/python${VERSION}${ABIFLAGS}"
 PLATINCDIR="-I$includedir/python${VERSION}${ABIFLAGS}"