diff --git a/lib/matplotlib/colorbar.py b/lib/matplotlib/colorbar.py
index a080eb59247c..5894ecf123c2 100644
--- a/lib/matplotlib/colorbar.py
+++ b/lib/matplotlib/colorbar.py
@@ -1117,9 +1117,10 @@ def make_axes(parents, location=None, orientation=None, fraction=0.15,
     parent_anchor = kw.pop('panchor', loc_settings['panchor'])
     pad = kw.pop('pad', loc_settings['pad'])
 
-    # turn parents into a list if it is not already
-    if not isinstance(parents, (list, tuple)):
-        parents = [parents]
+    # turn parents into a list if it is not already. We do this w/ np
+    # because `plt.subplots` can return an ndarray and is natural to
+    # pass to `colorbar`.
+    parents = np.atleast_1d(parents).ravel()
 
     fig = parents[0].get_figure()
     if not all(fig is ax.get_figure() for ax in parents):