diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
index 6d49806487f..34a934d8cd5 100644
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -13237,8 +13237,10 @@ formatfloat(PyObject *v, int flags, int prec, int type,
         return -1;
     len = strlen(p);
     if (writer) {
-        if (_PyUnicodeWriter_Prepare(writer, len, 127) == -1)
+        if (_PyUnicodeWriter_Prepare(writer, len, 127) == -1) {
+            PyMem_Free(p);
             return -1;
+        }
         unicode_write_cstr(writer->buffer, writer->pos, p, len);
         writer->pos += len;
     }