diff --git a/Orange/widgets/visualize/owscatterplotgraph.py b/Orange/widgets/visualize/owscatterplotgraph.py
index 80bddde560f..db81a89df52 100644
--- a/Orange/widgets/visualize/owscatterplotgraph.py
+++ b/Orange/widgets/visualize/owscatterplotgraph.py
@@ -302,7 +302,10 @@ def tickValues(self, minVal, maxVal, size):
             step = int(np.ceil(float(len(ticks)) / max_steps))
             ticks = ticks[::step]
 
-        spacing = min(b - a for a, b in zip(ticks[:-1], ticks[1:]))
+        # In case of a single tick, `default` will inform tickStrings
+        # about the appropriate scale.
+        spacing = min((b - a for a, b in zip(ticks[:-1], ticks[1:])),
+                      default=maxVal - minVal)
         return [(spacing, ticks)]
 
     def tickStrings(self, values, scale, spacing):
diff --git a/Orange/widgets/visualize/tests/test_owscatterplot.py b/Orange/widgets/visualize/tests/test_owscatterplot.py
index 88802d6328c..51e2b39adb3 100644
--- a/Orange/widgets/visualize/tests/test_owscatterplot.py
+++ b/Orange/widgets/visualize/tests/test_owscatterplot.py
@@ -1130,6 +1130,10 @@ def test_time_axis(self):
         with self.assertRaises(ValueError):
             float(ticks[0])
 
+        spacing, ticks = x_axis.tickValues(1581953776, 1582953776, 10)[0]
+        self.assertEqual(spacing, 1582953776 - 1581953776)
+        self.assertTrue(not ticks.size or 1581953776 <= ticks[0] <= 1582953776)
+
     def test_clear_plot(self):
         self.widget.cb_class_density.setChecked(True)
         self.send_signal(self.widget.Inputs.data, self.data)