diff --git a/Misc/NEWS.d/next/Library/2019-03-04-16-13-01.bpo-13096.SGPt_n.rst b/Misc/NEWS.d/next/Library/2019-03-04-16-13-01.bpo-13096.SGPt_n.rst
new file mode 100644
index 00000000000000..2bf49c855f60ca
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2019-03-04-16-13-01.bpo-13096.SGPt_n.rst
@@ -0,0 +1 @@
+Fix memory leak in ctypes POINTER handling of large values.
diff --git a/Modules/_ctypes/callproc.c b/Modules/_ctypes/callproc.c
index 2097342085788e..defcde1ff3e965 100644
--- a/Modules/_ctypes/callproc.c
+++ b/Modules/_ctypes/callproc.c
@@ -1831,6 +1831,7 @@ POINTER(PyObject *self, PyObject *cls)
                                        "s(O){}",
                                        buf,
                                        &PyCPointer_Type);
+        PyMem_Free(buf);
         if (result == NULL)
             return result;
         key = PyLong_FromVoidPtr(result);