diff --git a/src/components/state-history-chart-line.html b/src/components/state-history-chart-line.html
index 74d3d20e95..0f5e12e7cd 100644
--- a/src/components/state-history-chart-line.html
+++ b/src/components/state-history-chart-line.html
@@ -236,7 +236,9 @@
         }
 
         // Add an entry for final values
-        pushData([endTime].concat(prevValues.slice(1)), false);
+        if (prevValues) {
+          pushData([endTime].concat(prevValues.slice(1)), false);
+        }
 
         dataTable.addRows(data);
         return dataTable;
diff --git a/src/components/state-history-chart-timeline.html b/src/components/state-history-chart-timeline.html
index fa283727a1..dcedf39ca2 100644
--- a/src/components/state-history-chart-timeline.html
+++ b/src/components/state-history-chart-timeline.html
@@ -126,7 +126,9 @@ class StateHistoryChartTimeline extends
         }
       });
 
-      addRow(entityDisplay, prevState, prevLastChanged, endTime);
+      if (prevState !== null) {
+        addRow(entityDisplay, prevState, prevLastChanged, endTime);
+      }
       numTimelines++;
     });