diff --git a/dlls/urlmon/urlmon.spec b/dlls/urlmon/urlmon.spec
index 5be0b6a86eb..069421f4c73 100644
--- a/dlls/urlmon/urlmon.spec
+++ b/dlls/urlmon/urlmon.spec
@@ -105,3 +105,4 @@
 423 stdcall @(long long long long) LogSqmUXCommandOffsetInternal
 444 stdcall @(long long long) MapUriToBrowserEmulationState
 445 stdcall @(long long) MapBrowserEmulationModeToUserAgent
+455 stdcall @() FlushUrlmonZonesCache
diff --git a/dlls/urlmon/urlmon_main.c b/dlls/urlmon/urlmon_main.c
index 17e9d1489ad..a9c5a6d0461 100644
--- a/dlls/urlmon/urlmon_main.c
+++ b/dlls/urlmon/urlmon_main.c
@@ -1165,6 +1165,15 @@ int WINAPI MapBrowserEmulationModeToUserAgent(DWORD unk1, DWORD unk2)
     return 0;
 }
 
+/***********************************************************************
+ *           FlushUrlmonZonesCache (URLMON.455)
+ *    Undocumented, added in IE8
+ */
+void WINAPI FlushUrlmonZonesCache(void)
+{
+    FIXME("stub\n");
+}
+
 /***********************************************************************
  *            RegisterMediaTypes
  *    Added in IE3, registers known MIME-type strings.