diff --git a/include/wx/checkbox.h b/include/wx/checkbox.h
index 47a4e356d5..6b30a0a25f 100644
--- a/include/wx/checkbox.h
+++ b/include/wx/checkbox.h
@@ -99,19 +99,14 @@ public:
         DoSet3StateValue(state);
     }
 
-    bool Is3State() const
-    {
-        return (m_style & wxCHK_3STATE) != 0;
-    }
+    bool Is3State() const { return HasFlag(wxCHK_3STATE); }
 
     bool Is3rdStateAllowedForUser() const
     {
-        return (m_style & wxCHK_ALLOW_3RD_STATE_FOR_USER) != 0;
+        return HasFlag(wxCHK_ALLOW_3RD_STATE_FOR_USER);
     }
 
 protected:
-    int m_style;
-
     virtual void DoSet3StateValue(wxCheckBoxState WXUNUSED(state)) { wxFAIL; }
 
     virtual wxCheckBoxState DoGet3StateValue() const
diff --git a/src/mac/carbon/checkbox.cpp b/src/mac/carbon/checkbox.cpp
index dbf5b7d4e2..6e6aa299b2 100644
--- a/src/mac/carbon/checkbox.cpp
+++ b/src/mac/carbon/checkbox.cpp
@@ -34,8 +34,6 @@ bool wxCheckBox::Create(wxWindow *parent, wxWindowID id, const wxString& label,
     if ( !wxCheckBoxBase::Create(parent, id, pos, size, style, validator, name) )
         return false;
 
-    m_style = style;
-
     Rect bounds ;
     Str255 title ;
     
diff --git a/src/mac/checkbox.cpp b/src/mac/checkbox.cpp
index dbf5b7d4e2..6e6aa299b2 100644
--- a/src/mac/checkbox.cpp
+++ b/src/mac/checkbox.cpp
@@ -34,8 +34,6 @@ bool wxCheckBox::Create(wxWindow *parent, wxWindowID id, const wxString& label,
     if ( !wxCheckBoxBase::Create(parent, id, pos, size, style, validator, name) )
         return false;
 
-    m_style = style;
-
     Rect bounds ;
     Str255 title ;
     
diff --git a/src/msw/checkbox.cpp b/src/msw/checkbox.cpp
index e8c6ec263e..494819949d 100644
--- a/src/msw/checkbox.cpp
+++ b/src/msw/checkbox.cpp
@@ -143,8 +143,6 @@ bool wxCheckBox::Create(wxWindow *parent,
     if ( !CreateControl(parent, id, pos, size, style, validator, name) )
         return FALSE;
 
-    m_style = style;
-
     long msStyle = WS_TABSTOP;
 
     if ( style & wxCHK_3STATE )