diff --git a/modelcif/dumper.py b/modelcif/dumper.py
index ffde320..a89e8df 100644
--- a/modelcif/dumper.py
+++ b/modelcif/dumper.py
@@ -20,8 +20,8 @@ def dump(self, system, writer):
         with writer.category("_audit_conform") as lp:
             # Update to match the version of the ModelCIF dictionary
             # we support:
-            lp.write(dict_name="mmcif_ma.dic", dict_version="1.4.5",
-                     dict_location=self.URL % "ba728c4")
+            lp.write(dict_name="mmcif_ma.dic", dict_version="1.4.6",
+                     dict_location=self.URL % "d18ba38")
 
 
 class _EntryLinkDumper(Dumper):