diff --git a/broker_sync/sinks/wealthfolio.py b/broker_sync/sinks/wealthfolio.py
index e6dce17..807263f 100644
--- a/broker_sync/sinks/wealthfolio.py
+++ b/broker_sync/sinks/wealthfolio.py
@@ -155,6 +155,9 @@ class WealthfolioSink:
             "activityType": str(a.activity_type),
             "currency": a.currency,
             "accountId": a.account_id,
+            # Required booleans on ActivityImport (no defaults in Rust struct).
+            "isDraft": False,
+            "isValid": True,
         }
         if a.quantity is not None:
             row["quantity"] = format(a.quantity, "f")