diff --git a/tempest/common/waiters.py b/tempest/common/waiters.py
index 11f3bf9..251d130 100644
--- a/tempest/common/waiters.py
+++ b/tempest/common/waiters.py
@@ -124,6 +124,12 @@
             raise lib_exc.DeleteErrorException(
                 "Server %s failed to delete and is in ERROR status" %
                 server_id)
+        if server_status == 'SOFT_DELETED':
+            # Soft-deleted instances need to be forcibly deleted to
+            # prevent some test cases from failing.
+            LOG.debug("Automatically force-deleting soft-deleted server %s",
+                      server_id)
+            client.force_delete_server(server_id)
 
         if int(time.time()) - start_time >= client.build_timeout:
             raise lib_exc.TimeoutException