diff --git a/numpy/core/src/multiarray/dtype_transfer.c b/numpy/core/src/multiarray/dtype_transfer.c
index 630bd76f3955..9b93ecde43a2 100644
--- a/numpy/core/src/multiarray/dtype_transfer.c
+++ b/numpy/core/src/multiarray/dtype_transfer.c
@@ -1138,10 +1138,10 @@ get_datetime_to_unicode_transfer_function(int aligned,
 
     /* Get an ASCII string data type, adapted to match the UNICODE one */
     str_dtype = PyArray_DescrNewFromType(NPY_STRING);
-    str_dtype->elsize = dst_dtype->elsize / 4;
     if (str_dtype == NULL) {
         return NPY_FAIL;
     }
+    str_dtype->elsize = dst_dtype->elsize / 4;
 
     /* Get the copy/swap operation to dst */
     if (PyArray_GetDTypeCopySwapFn(aligned,