@@ -2087,10 +2087,12 @@ class _VectorizedFinalizedBuilderMixin(_FinalizedBuilderMixin):

         to_family = self.site_arrays[to_which].family

         to_tags = self.site_arrays[to_which].tags

         to_site_array = SiteArray(to_family, to_tags[to_off])

+        site_arrays = (to_site_array,)

         if not is_onsite:

             from_family = self.site_arrays[from_which].family

             from_tags = self.site_arrays[from_which].tags

             from_site_array = SiteArray(from_family, from_tags[from_off])

+            site_arrays = self.symmetry.to_fd(to_site_array, from_site_array)

         # Construct args from params

         if params:

@@ -2107,20 +2109,10 @@ class _VectorizedFinalizedBuilderMixin(_FinalizedBuilderMixin):

                        ', '.join(map('"{}"'.format, missing)))

                 raise TypeError(''.join(msg))

-        if is_onsite:

-            try:

-                ham = val(to_site_array, *args)

-            except Exception as exc:

-                _raise_user_error(exc, val)

-        else:

-            try:

-                ham = val(

-                        *self.symmetry.to_fd(

-                            to_site_array,

-                            from_site_array),

-                        *args)

-            except Exception as exc:

-                _raise_user_error(exc, val)

+        try:

+            ham = val(*site_arrays, *args)

+        except Exception as exc:

+            _raise_user_error(exc, val)

         expected_shape = (

             len(to_site_array),