diff --git a/dlls/mshtml/htmldoc.c b/dlls/mshtml/htmldoc.c
index 87be6535cac..784a578b2ed 100644
--- a/dlls/mshtml/htmldoc.c
+++ b/dlls/mshtml/htmldoc.c
@@ -921,8 +921,11 @@ static HRESULT WINAPI HTMLDocument_put_defaultCharset(IHTMLDocument2 *iface, BST
 static HRESULT WINAPI HTMLDocument_get_defaultCharset(IHTMLDocument2 *iface, BSTR *p)
 {
     HTMLDocument *This = impl_from_IHTMLDocument2(iface);
-    FIXME("(%p)->(%p)\n", This, p);
-    return E_NOTIMPL;
+
+    TRACE("(%p)->(%p)\n", This, p);
+
+    *p = charset_string_from_cp(GetACP());
+    return *p ? S_OK : E_OUTOFMEMORY;
 }
 
 static HRESULT WINAPI HTMLDocument_get_mimeType(IHTMLDocument2 *iface, BSTR *p)
diff --git a/dlls/mshtml/main.c b/dlls/mshtml/main.c
index 0b6f6aca8a5..8a366bd9537 100644
--- a/dlls/mshtml/main.c
+++ b/dlls/mshtml/main.c
@@ -54,24 +54,34 @@ static HDC display_dc;
 static WCHAR *status_strings[IDS_STATUS_LAST-IDS_STATUS_FIRST+1];
 static IMultiLanguage2 *mlang;
 
+static BOOL ensure_mlang(void)
+{
+    IMultiLanguage2 *new_mlang;
+    HRESULT hres;
+
+    if(mlang)
+        return TRUE;
+
+    hres = CoCreateInstance(&CLSID_CMultiLanguage, NULL, CLSCTX_INPROC_SERVER,
+            &IID_IMultiLanguage2, (void**)&new_mlang);
+    if(FAILED(hres)) {
+        ERR("Could not create CMultiLanguage instance\n");
+        return FALSE;
+    }
+
+    if(InterlockedCompareExchangePointer((void**)&mlang, new_mlang, NULL))
+        IMultiLanguage2_Release(new_mlang);
+
+    return TRUE;
+}
+
 UINT cp_from_charset_string(BSTR charset)
 {
     MIMECSETINFO info;
     HRESULT hres;
 
-    if(!mlang) {
-        IMultiLanguage2 *new_mlang;
-
-        hres = CoCreateInstance(&CLSID_CMultiLanguage, NULL, CLSCTX_INPROC_SERVER,
-                &IID_IMultiLanguage2, (void**)&new_mlang);
-        if(FAILED(hres)) {
-            ERR("Could not create CMultiLanguage instance\n");
-            return CP_UTF8;
-        }
-
-        if(InterlockedCompareExchangePointer((void**)&mlang, new_mlang, NULL))
-            IMultiLanguage2_Release(new_mlang);
-    }
+    if(!ensure_mlang())
+        return CP_UTF8;
 
     hres = IMultiLanguage2_GetCharsetInfo(mlang, charset, &info);
     if(FAILED(hres)) {
@@ -82,6 +92,23 @@ UINT cp_from_charset_string(BSTR charset)
     return info.uiInternetEncoding;
 }
 
+BSTR charset_string_from_cp(UINT cp)
+{
+    MIMECPINFO info;
+    HRESULT hres;
+
+    if(!ensure_mlang())
+        return SysAllocString(NULL);
+
+    hres = IMultiLanguage2_GetCodePageInfo(mlang, cp, GetUserDefaultUILanguage(), &info);
+    if(FAILED(hres)) {
+        ERR("GetCodePageInfo failed: %08x\n", hres);
+        return SysAllocString(NULL);
+    }
+
+    return SysAllocString(info.wszWebCharset);
+}
+
 static void thread_detach(void)
 {
     thread_data_t *thread_data;
diff --git a/dlls/mshtml/mshtml_private.h b/dlls/mshtml/mshtml_private.h
index 2f03501bc19..f57dff24a34 100644
--- a/dlls/mshtml/mshtml_private.h
+++ b/dlls/mshtml/mshtml_private.h
@@ -1271,6 +1271,7 @@ static inline void windowref_release(windowref_t *ref)
 }
 
 UINT cp_from_charset_string(BSTR) DECLSPEC_HIDDEN;
+BSTR charset_string_from_cp(UINT) DECLSPEC_HIDDEN;
 HDC get_display_dc(void) DECLSPEC_HIDDEN;
 HINSTANCE get_shdoclc(void) DECLSPEC_HIDDEN;
 void set_statustext(HTMLDocumentObj*,INT,LPCWSTR) DECLSPEC_HIDDEN;