diff --git a/include/wx/html/htmlpars.h b/include/wx/html/htmlpars.h
index 2f769eadab..66f2de8db4 100644
--- a/include/wx/html/htmlpars.h
+++ b/include/wx/html/htmlpars.h
@@ -262,16 +262,16 @@ public:
 
     // Parses entities in input and replaces them with respective characters
     // (with respect to output encoding)
-    wxString Parse(const wxString& input);
+    wxString Parse(const wxString& input) const;
 
     // Returns character for given entity or 0 if the enity is unknown
-    wxChar GetEntityChar(const wxString& entity);
+    wxChar GetEntityChar(const wxString& entity) const;
 
     // Returns character that represents given Unicode code
 #if wxUSE_UNICODE
-    wxChar GetCharForCode(unsigned code) { return (wxChar)code; }
+    wxChar GetCharForCode(unsigned code) const { return (wxChar)code; }
 #else
-    wxChar GetCharForCode(unsigned code);
+    wxChar GetCharForCode(unsigned code) const;
 #endif
 
 protected:
diff --git a/src/html/htmlpars.cpp b/src/html/htmlpars.cpp
index 9d3bf3cb8e..2d3b86f1ee 100644
--- a/src/html/htmlpars.cpp
+++ b/src/html/htmlpars.cpp
@@ -474,7 +474,7 @@ void wxHtmlEntitiesParser::SetEncoding(wxFontEncoding encoding)
 #endif
 }
 
-wxString wxHtmlEntitiesParser::Parse(const wxString& input)
+wxString wxHtmlEntitiesParser::Parse(const wxString& input) const
 {
     const wxChar *c, *last;
     const wxChar *in_str = input.c_str();
@@ -520,7 +520,7 @@ wxString wxHtmlEntitiesParser::Parse(const wxString& input)
 }
 
 #if !wxUSE_UNICODE
-wxChar wxHtmlEntitiesParser::GetCharForCode(unsigned code)
+wxChar wxHtmlEntitiesParser::GetCharForCode(unsigned code) const
 {
 #if wxUSE_WCHAR_T
     char buf[2];
@@ -552,7 +552,7 @@ extern "C" int LINKAGEMODE wxHtmlEntityCompare(const void *key, const void *item
 #endif
 }
 
-wxChar wxHtmlEntitiesParser::GetEntityChar(const wxString& entity)
+wxChar wxHtmlEntitiesParser::GetEntityChar(const wxString& entity) const
 {
     unsigned code = 0;