diff --git a/flow/connectors/eventhub/partition_hash.go b/flow/connectors/eventhub/partition_hash.go
index 6445f3281..f8ebe56fa 100644
--- a/flow/connectors/eventhub/partition_hash.go
+++ b/flow/connectors/eventhub/partition_hash.go
@@ -14,6 +14,10 @@ func hashString(s string) uint32 {
 }
 
 func HashedPartitionKey(s string, numPartitions uint32) string {
+	if numPartitions == 0 {
+		return "0"
+	}
+
 	partition := hashString(s) % numPartitions
 	return strconv.FormatUint(uint64(partition), 10)
 }