diff --git a/packages/db/migrations/20260329_020000_fix_household_item_classification_upsert.sql b/packages/db/migrations/20260329_020000_fix_household_item_classification_upsert.sql
new file mode 100644
index 0000000..29e0133
--- /dev/null
+++ b/packages/db/migrations/20260329_020000_fix_household_item_classification_upsert.sql
@@ -0,0 +1,23 @@
+BEGIN;
+
+WITH ranked_classifications AS (
+  SELECT
+    id,
+    ROW_NUMBER() OVER (
+      PARTITION BY household_id, store_id, household_store_item_id
+      ORDER BY updated_at DESC NULLS LAST, id DESC
+    ) AS row_rank
+  FROM household_item_classifications
+  WHERE household_store_item_id IS NOT NULL
+)
+DELETE FROM household_item_classifications hic
+USING ranked_classifications ranked
+WHERE hic.id = ranked.id
+  AND ranked.row_rank > 1;
+
+DROP INDEX IF EXISTS idx_household_item_classifications_household_store_item;
+
+CREATE UNIQUE INDEX idx_household_item_classifications_household_store_item
+  ON household_item_classifications(household_id, store_id, household_store_item_id);
+
+COMMIT;