diff --git a/panel/param.py b/panel/param.py
index 2afa5f0d2e..a1aef26a4c 100644
--- a/panel/param.py
+++ b/panel/param.py
@@ -492,7 +492,7 @@ def widget(self_or_cls, p_name: str, parameterized: param.Parameterized | None =
                 kw['start'] = bounds[0]
             if bounds[1] is not None:
                 kw['end'] = bounds[1]
-            if (('start' not in kw or 'end' not in kw) and
+            if (('start' not in kw or 'end' not in kw or value is None) and
                 not isinstance(p_obj, (param.Date, param.CalendarDate))):
                 # Do not change widget class if mapping was overridden
                 if not widget_class_overridden:
diff --git a/panel/tests/test_param.py b/panel/tests/test_param.py
index d8aab010b7..9e1bdc237d 100644
--- a/panel/tests/test_param.py
+++ b/panel/tests/test_param.py
@@ -8,8 +8,8 @@
 from bokeh.models import (
     AutocompleteInput as BkAutocompleteInput, Button as BkButton,
     Checkbox as BkCheckbox, Column as BkColumn, Div, MultiSelect,
-    RangeSlider as BkRangeSlider, Row as BkRow, Select, Slider, Tabs as BkTabs,
-    TextInput, TextInput as BkTextInput, Toggle,
+    RangeSlider as BkRangeSlider, Row as BkRow, Select, Slider, Spinner,
+    Tabs as BkTabs, TextInput, TextInput as BkTextInput, Toggle,
 )
 from packaging.version import Version
 
@@ -201,6 +201,16 @@ class Test(param.Parameterized):
     assert slider.end == 5.5
     assert slider.disabled == True
 
+def test_number_param_with_none(document, comm):
+    class Test(param.Parameterized):
+        a = param.Number(default=None, bounds=(0, 5))
+
+    test = Test()
+    test_pane = Param(test)
+    model = test_pane.get_root(document, comm=comm)
+
+    slider = model.children[1]
+    assert isinstance(slider, Spinner)
 
 def test_boolean_param(document, comm):
     class Test(param.Parameterized):