diff --git a/hbrdd/dbf/indexer.go b/hbrdd/dbf/indexer.go
index 3932386..7ae0bcf 100644
--- a/hbrdd/dbf/indexer.go
+++ b/hbrdd/dbf/indexer.go
@@ -91,8 +91,12 @@ func (a *DBFArea) OrderCreate(params hbrdd.OrderCreateParams) error {
 	}
 
 	// Sort keys before building index
+	// Harbour: equal keys ordered by RecNo ascending (stable by record number)
 	sort.Slice(keys, func(i, j int) bool {
 		cmp := bytes.Compare(keys[i].Key, keys[j].Key)
+		if cmp == 0 {
+			return keys[i].RecNo < keys[j].RecNo
+		}
 		if params.Descending {
 			return cmp > 0
 		}