diff --git a/migrations/008_add_sub_label.py b/migrations/008_add_sub_label.py
index eae88af31..442355034 100644
--- a/migrations/008_add_sub_label.py
+++ b/migrations/008_add_sub_label.py
@@ -38,7 +38,7 @@ SQL = pw.SQL
 def migrate(migrator, database, fake=False, **kwargs):
     migrator.add_fields(
         Event,
-        sub_label=pw.CharField(default=None),
+        sub_label=pw.CharField(default=None, null=True),
     )