diff --git a/Include/pymacro.h b/Include/pymacro.h
index 73521be00fcd1ad..cde2a5fd05ad585 100644
--- a/Include/pymacro.h
+++ b/Include/pymacro.h
@@ -1,12 +1,7 @@
 #ifndef Py_PYMACRO_H
 #define Py_PYMACRO_H
 
-// _Py_STDC_VERSION: the version of the C standard.
-// gh-160208: The C++ standard allows __STDC_VERSION__ to be defined to an
-// arbitrary value, which means we can't use __STDC_VERSION__ on C++.
-#if !defined(__cplusplus) && defined(__STDC_VERSION__)
-#  define _Py_STDC_VERSION __STDC_VERSION__
-#endif
+// _Py_STDC_VERSION is defined in pyport.h, which is included before this file.
 
 // gh-91782: On FreeBSD 12, if the _POSIX_C_SOURCE and _XOPEN_SOURCE macros are
 // defined, <sys/cdefs.h> disables C11 support and <assert.h> does not define
diff --git a/Include/pyport.h b/Include/pyport.h
index 3de7fb3d317521a..821e68ee89e23f7 100644
--- a/Include/pyport.h
+++ b/Include/pyport.h
@@ -8,6 +8,15 @@
 #  error "Python's source code assumes C's unsigned char is an 8-bit type"
 #endif
 
+// _Py_STDC_VERSION: the version of the C standard.
+// gh-160208: The C++ standard allows __STDC_VERSION__ to be defined to an
+// arbitrary value, which means we can't use __STDC_VERSION__ on C++.
+// gh-160719: Defined here, rather than in pymacro.h, because this file uses it
+// and is included before pymacro.h.
+#if !defined(__cplusplus) && defined(__STDC_VERSION__)
+#  define _Py_STDC_VERSION __STDC_VERSION__
+#endif
+
 
 // Preprocessor check for a builtin preprocessor function. Always return 0
 // if __has_builtin() macro is not defined.
diff --git a/Misc/NEWS.d/next/C_API/2026-10-26-19-10-00.gh-issue-160719.F9F7fw.rst b/Misc/NEWS.d/next/C_API/2026-10-26-19-10-00.gh-issue-160719.F9F7fw.rst
new file mode 100644
index 000000000000000..622afb2d70cfee0
--- /dev/null
+++ b/Misc/NEWS.d/next/C_API/2026-10-26-19-10-00.gh-issue-160719.F9F7fw.rst
@@ -0,0 +1,5 @@
+Fix the C11 and C23 code paths in :file:`pyport.h` never being used: the
+private ``_Py_STDC_VERSION`` macro was defined in :file:`pymacro.h`, which is
+included after :file:`pyport.h`, so ``_Py_thread_local``, ``_Py_NULL`` and
+``_Py_TYPEOF`` fell back to compiler extensions instead of ``_Thread_local``,
+``nullptr`` and ``typeof``.