diff --git a/kikit/panelize.py b/kikit/panelize.py
index b758a9fa..4795ea47 100644
--- a/kikit/panelize.py
+++ b/kikit/panelize.py
@@ -615,7 +615,10 @@ def save(self, reconstructArcs: bool=False, refillAllZones: bool=False,
             if zName.startswith("KIKIT_zone_"):
                 zonesToRefill.append(zone)
                 zone.SetZoneName(originalZoneNames[zName])
-        fillerTool.Fill(zonesToRefill)
+        if len(zonesToRefill) > 0:
+            # Even if there are no zones to refill, the refill algorithm takes
+            # non-trivial time to compute, hence, skip it.
+            fillerTool.Fill(zonesToRefill)
 
         fillBoard.Save(self.filename)
         self._adjustPageSize()